8ba 275 carb options

[Alberta50fordor]

Hey guys, I recently picked up a rebuilt a rebuilt 8ba, the guy I got it from didn't know much about (he had it listed as a 239) from what I’ve found it was done in the 80’s and it’s been sitting since, I found it has the 4” crank, bored .030 over, came with the offenhauser tri power intake and old offenhauser heads stamped 325, according to an old offenhauser chart that I found it’s now a 275 and with those heads it’s 11.3:1 compression, I also picked up a super dual intake as an option
My question is can I run the single carb intake on this engine since the stock 255 was ran with the the single 94, and can I run 87 octane fuel with these head or do I need 91?, I also have a set of the aluminum Ford 8ba heads I was considering running.
I do drive the car quite frequently pretty much year round so reliability and economy is more of a concern to me over speed(the first year I ran the car with a worn out 239 and this past year I’ve been running with another engine with incorrectly adjusted valves and a misfire)

[flatjack9]

For a daily driver, I would use the 94 and the Ford heads.

[Newc]

In fact the 8cm or EAC Merc heads will help lower compression slightly over 8ba's or EAB heads. All late '49+ heads will ship by pair in a large Flat rate USPS box, reinforced inside, 45lbs on a limit of 70lbs. Postal rate increase about Jan 22 2023. Newc

[40cpe]

That piston reads 3 5/16 and .030. Would that be .030 over 3 5/16?

[tubman]

I hate to sound like a broken record, but the best carburetion for the engine you have and the way you drive is a small base Rochester 2G from a 265 or 283 SBC on a bored out Mercury 4-bolt manifold. The small base 2G flows about as much as 2 94's or 97's and is a lot easier to tune. You will have to change the distributor to use one though.

Also, I wouldn't put a lot of faith in the CR numbers from the manufacturers charts. There are too many factors affecting the final CR. The heads should also be checked and modified for optimum efficiency (increasing both performance and economy). The camshaft can also effect the dynamic compression ratio; do you know what's in your engine?

[tubman]

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Originally Posted by 40cpe

That piston reads 3 5/16 and .030. Would that be .030 over 3 5/16?

It sure looks like it!

[oldbugger]

2Xon the 2G, works great with chev dist

[cadillac512]

With that bore (3.3425") and the 4" crank you have 280.8 cubic inches. As for the heads, no way is it even close to 11:1 compression...maybe between 8 and 9:1. I also agree with the 2G Rochester setup, but to answer your question... yes the single 94 will work and will have great power down low but limit top end.

[Alberta50fordor]

Originally Posted by Newc

In fact the 8cm or EAC Merc heads will help lower compression slightly over 8ba's or EAB heads. All late '49+ heads will ship by pair in a large Flat rate USPS box, reinforced inside, 45lbs on a limit of 70lbs. Postal rate increase about Jan 22 2023. Newc

I’ve got a bunch of stock cast iron heads, if these offenhauser heads don’t have too high compression then I’ll run them, I wanted aftermarket ones for better cooling in the summer anyway, my other concern about the higher compression is the starter being able to keep up
The aluminum 8ba heads I have are from early 49 from what I’ve researched, same dimensions as the regular 8ba heads just made from aluminum( in Canada) due to an iron shortage supposedly?

[Alberta50fordor]

Originally Posted by flatjack9

Your engine is not 275 cubes, more like 260 cubes. That will lower your compression some. For a daily driver, I would use the 94 and the Ford heads.

So there shouldn’t be any fueling issues or having it run too lean with the single 94? That’s what some people have told me, as a daily could those offenhauser heads still work?

[V8COOPMAN]

Originally Posted by Alberta50fordor

I’ve got a bunch of stock cast iron heads, if these offenhauser heads don’t have too high compression then I’ll run them, I wanted aftermarket ones for better cooling in the summer anyway, my other concern about the higher compression is the starter being able to keep up

Because of the very design of the transfer area in a flathead engine, it just about impossible to end-up with TOO HIGH of a compression ratio.

Sounds like you need to steer clear of all the flathead experts you have been talking to up until now.

Coop

.

[Alberta50fordor]

Originally Posted by tubman

I hate to sound like a broken record, but the best carburetion for the engine you have and the way you drive is a small base Rochester 2G from a 265 or 283 SBC on a bored out Mercury 4-bolt manifold. The small base 2G flows about as much as 2 94's or 97's and is a lot easier to tune. You will have to change the distributor to use one though.

Also, I wouldn't put a lot of faith in the CR numbers from the manufacturers charts. There are too many factors affecting the final CR. The heads should also be checked and modified for optimum efficiency (increasing both performance and economy). The camshaft can also effect the dynamic compression ratio; do you know what's in your engine?

Yeah, ideally I’d run the 4bbl but I haven’t been able to find one yet, there is one on rock auto last time we looked for out 55 bel air but then it’s another 800 or so and I have a surplus of 94’s especially since the tri power came all set up with three other than the fuel lines, the distributer is planned, 12 volt is first though and I needed to buy a 12v solenoid for the overdrive, how do you modify the offenhauser heads for efficiency? I have a hunch it’s a stock cam due to the high compression heads so there can’t be much lift, it’s another thing I need to check, I can just see how much a valve moves off it’s seat? The guy who built the engine just stuck a stock distributer in with the tri power which seamed a little odd unless he changed out the springs?

[Alberta50fordor]

Originally Posted by V8COOPMAN

Because of the very design of the transfer area in a flathead engine, it just about impossible to end-up with TOO HIGH of a compression ratio.

Sounds like you need to steer clear of all the flathead experts you have been talking to up until now.

Coop

.

The guy who said it would be too lean with the single carb doesn’t know flatheads… he’s a newer Chevy guy, the one flathead guy that i spoke to whole builds them said it might be a little tough to get enough fuel and air into it with a single
I also considered relieving and porting but that would involve completely disassembling and not sure it would be worth the gain

[Alberta50fordor]

Originally Posted by cadillac512

With that bore (3.3425") and the 4" crank you have 280.8 cubic inches. As for the heads, no way is it even close to 11:1 compression...maybe between 8 and 9:1. I also agree with the 2G Rochester setup, but to answer your question... yes the single 94 will work and will have great power down low but limit top end.

So it should cause any damage running a single 94 for now? Part of why I was going to keep it on a single with this engine was for break in and get everything set up to run multiple or 4bbl
And then my question with the heads is having to run higher octane or not

[tubman]

Originally Posted by Alberta50fordor

Yeah, ideally I’d run the 4bbl but I haven’t been able to find one yet, there is one on rock auto last time we looked for out 55 bel air but then it’s another 800 or so and I have a surplus of 94’s especially since the tri power came all set up with three other than the fuel lines, the distributer is planned, 12 volt is first though and I needed to buy a 12v solenoid for the overdrive, how do you modify the offenhauser heads for efficiency? I have a hunch it’s a stock cam due to the high compression heads so there can’t be much lift, it’s another thing I need to check, I can just see how much a valve moves off it’s seat? The guy who built the engine just stuck a stock distributer in with the tri power which seamed a little odd unless he changed out the springs?

Just so you know, a 2G is a two-barrel carburetor used on the early SBC's and other GM V8's. They come in two basic varieties; small base and large base. The mounting bolt patterns are different. The small base variety will bolt to a stock '49-'53 Mercury manifold which is a a bolt on for a Ford. They are quite a bit cheaper and less complicated than a 4 barrel. The throttle bores are bigger than the Mercury manifold and it should be bored out to match the carburetor

Any heads you use. whether stock or aftermarket, should be checked for fit. Basically you want to get a uniform clearance of .045" to 050" over the piston crown. There are several threads on here and the H.A.M.B. that detail the process. If you have the manifold off. check for the presence of adjustable lifters. If present, chances are you have an after market cam.

The 8BA series of flatheads used a different advance system than other cars. It is called a Load-a-Matic system. It is vacuum advance only with no mechanical (centrifugal) advance. It uses a vacuum signal taken of of a port on the middle back of the carb. Using regular manifold vacuum (or even ported vacuum) will cause the distributor's advance system to function improperly. The solution is to use either an old Mallory dual point distributor or have a SBC distributor converted to fit your engine. Since the springs inside the distributor only function to control the special vacuum signal, changing them won't hep.

[cadillac512]

Originally Posted by Alberta50fordor

So it should cause any damage running a single 94 for now? Part of why I was going to keep it on a single with this engine was for break in and get everything set up to run multiple or 4bbl
And then my question with the heads is having to run higher octane or not

No, it won't cause any damage. Actually it's a good plan to break it in and make sure all is well before modifying the fuel system. My bet is that you'll be fine on regular fuel. The compression is just not going to be that high.

More important will be ensuring that the radiator is absolutely clean, correct and in good condition.

[Alberta50fordor]

Originally Posted by tubman

Just so you know, a 2G is a two-barrel carburetor used on the early SBC's and other GM V8's. They come in two basic varieties; small base and large base. The mounting bolt patterns are different. The small base variety will bolt to a stock '49-'53 Mercury manifold which is a a bolt on for a Ford. They are quite a bit cheaper and less complicated than a 4 barrel. The throttle bores are bigger than the Mercury manifold and it should be bored out to match the carburetor

Any heads you use. whether stock or aftermarket, should be checked for fit. Basically you want to get a uniform clearance of .045" to 050" over the piston crown. There are several threads on here and the H.A.M.B. that detail the process. If you have the manifold off. check for the presence of adjustable lifters. If present, chances are you have an after market cam.

The 8BA series of flatheads used a different advance system than other cars. It is called a Load-a-Matic system. It is vacuum advance only with no mechanical (centrifugal) advance. It uses a vacuum signal taken of of a port on the middle back of the carb. Using regular manifold vacuum (or even ported vacuum) will cause the distributor's advance system to function improperly. The solution is to use either an old Mallory dual point distributor or have a SBC distributor converted to fit your engine. Since the springs inside the distributor only function to control the special vacuum signal, changing them won't hep.

Right, I should have payed more attention, I thought you were referring to the small 4bbl that came on the Chevy 265, as for lifters yes it has adjustables, is there a way to see what cam is has without pulling it out?
There a bigger 2bbl carb mounted on an intake in ns, it looks like it’s a 4 volt base

[Alberta50fordor]

Originally Posted by cadillac512

No, it won't cause any damage. Actually it's a good plan to break it in and make sure all is well before modifying the fuel system. My bet is that you'll be fine on regular fuel. The compression is just not going to be that high.

More important will be ensuring that the radiator is absolutely clean, correct and in good condition.

Fine on regular with the 325 heads?
I’ve flushed the rad out several times the last time was with vinegar, it is the correct one for a shoebox

[jimvette59]

FYI, I have a 67 327 300 hp SBC with a wcfb that the primaries are 15/16 the same size as a 94

[cadillac512]

Originally Posted by Alberta50fordor

Fine on regular with the 325 heads?
I’ve flushed the rad out several times the last time was with vinegar, it is the correct one for a shoebox

Pretty good chance it'll be fine with the 325 heads. Without actually checking the cc's of the chambers you can't know exactly how they compare with stock heads, but it's VERY difficult to get even moderately high compression on a flathead without a lot of work and modification.


UPDATE! I found the chart listing the heads. VERY small chambers that may well do just as you said...too much compression for pump gas. I apologize for the misinformation...I didn't know those heads existed.
Hopefully Pete may offer an opinion...he is a good source of info on this type of situation.


Terry

[Alberta50fordor]

Originally Posted by cadillac512

Pretty good chance it'll be fine with the 325 heads. Without actually checking the cc's of the chambers you can't know exactly how they compare with stock heads, but it's VERY difficult to get even moderately high compression on a flathead without a lot of work and modification.


UPDATE! I found the chart listing the heads. VERY small chambers that may well do just as you said...too much compression for pump gas. I apologize for the misinformation...I didn't know those heads existed.
Hopefully Pete may offer an opinion...he is a good source of info on this type of situation.


Terry

lol its probably the chart that i tried posting but it was a screenshot from my phone that didn't work apparently, is there a benefit to running heads with a chamber this small on this engine? not knowing yet what cam is in it
https://offenhauser.co/wp-content/up...talog-1987.pdf

[tubman]

The first thing you should do with the heads is check the clearance over the piston dome and the valves. A lot of used aluminum heads have been milled and may not even clear. Used heads sometimes have severe corrosion problems.

You will be well served finding out exactly where you are and what you have before making any big decisions. Some (most?) cams are marked on the nose which can help identify them. Pull the front cover and see what you can see. It would also be informative to determine if it has an aluminum or fiber timing gear.

[Alberta50fordor]

Originally Posted by tubman

The first thing you should do with the heads is check the clearance over the piston dome and the valves. A lot of used aluminum heads have been milled and may not even clear. Used heads sometimes have severe corrosion problems.

You will be well served finding out exactly where you are and what you have before making any big decisions. Some (most?) cams are marked on the nose which can help identify them. Pull the front cover and see what you can see. It would also be informative to determine if it has an aluminum or fiber timing gear.

As far as I know these heads haven’t been ran from looking at them, EAB-A stamped on the end of the cam so I’m guessing it’s a stock cam?
Also, are the old valves ok to use? How long to the old ones typically last?

[tubman]

If you're planning on running this engine in a '50 Ford Fordor, that's a pretty good cam for your application. I don't think it would be worth the time, money and effort to upgrade to an aftermarket cam.

From what I can see from the pictures supplied, that looks like a fresh engine. I don't think the valves will be much of a problem. I still think you should check the heads. Put pea-sized aluminum foil balls on the valves and crown of the pistons. Bolt the heads on without gaskets (4-6 bolts will do), and try to turn the engine over. If it stops, don't force it and try again with a set of gaskets (used will do). When you get it to turn a couple times, pull the heads and measure the foil balls with a caliper. You will be looking for .045-.050" over the piston crowns and .060" over the valves. Remember that a compressed head gasket is about .055", so be sure to take that into consideration.

Let us know what you find. Second-hand knowledge and published specs are not always reliable. I had a set of used Edmunds heads that had to have .025" milled off of them to bring the quench to optimum.

[Alberta50fordor]

Originally Posted by tubman

If you're planning on running this engine in a '50 Ford Fordor, that's a pretty good cam for your application. I don't think it would be worth the time, money and effort to upgrade to an aftermarket cam.

From what I can see from the pictures supplied, that looks like a fresh engine. I don't think the valves will be much of a problem. I still think you should check the heads. Put pea-sized aluminum foil balls on the valves and crown of the pistons. Bolt the heads on without gaskets (4-6 bolts will do), and try to turn the engine over. If it stops, don't force it and try again with a set of gaskets (used will do). When you get it to turn a couple times, pull the heads and measure the foil balls with a caliper. You will be looking for .045-.050" over the piston crowns and .060" over the valves. Remember that a compressed head gasket is about .055", so be sure to take that into consideration.

Let us know what you find. Second-hand knowledge and published specs are not always reliable. I had a set of used Edmunds heads that had to have .025" milled off of them to bring the quench to optimum.

for now i might put ford heads on, should i check for clearance with those too? should i change out the fiber timing gear? shouldn't there also be locks on the bolt heads?

[tubman]

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Originally Posted by Alberta50fordor

for now i might put ford heads on, should i check for clearance with those too? should i change out the fiber timing gear? shouldn't there also be locks on the bolt heads?

I would check the Ford heads only if I were to plan on reworking them and running them permanently. Reworking iron heads is a lot more work than aluminum ones. I prefer aluminum timing gears, but that being said, your gear looks good and should work well. I have never seen a stripped original Ford cam gear on a flathead, though I have seen them on SBC's. The aftermarket gears are another thing entirely.

As to locks on the bolts, I do not know, since my machinist always assembles my engines and installs the cams. He is set up for it, while I am not. I'm sure someone else here has your answer.

[Bill OH]

Run an Aluminum gear and use locks on the cam bolts. I stripped a fiber gear in an 8ba!!! Return the oil from the filter to the top of the timing cover - it helps the longevity of the gear.

[Alberta50fordor]

Originally Posted by tubman

I would check the Ford heads only if I were to plan on reworking them and running them permanently. Reworking iron heads is a lot more work than aluminum ones. I prefer aluminum timing gears, but that being said, your gear looks good and should work well. I have never seen a stripped original Ford cam gear on a flathead, though I have seen them on SBC's. The aftermarket gears are another thing entirely.

As to locks on the bolts, I do not know, since my machinist always assembles my engines and installs the cams. He is set up for it, while I am not. I'm sure someone else here has your answer.

So i have those aluminum canadian ford heads or several 8ba cast iron heads, i also have a set of "mercury" heads on another old locked up engine, would there be any benefit running truck(RT) heads on this engine?

[tubman]

Originally Posted by Alberta50fordor

So i have those aluminum canadian ford heads or several 8ba cast iron heads, i also have a set of "mercury" heads on another old locked up engine, would there be any benefit running truck(RT) heads on this engine?

None at all. Those are the lowest compression of all the production 8BA Ford heads.

[Ol' Ron]

tUBMAN HAS THE ANSWERS, THE 2gc IS THE BEST ANSWERE FOR THIS APPLICATION.
gRAMPS
Sorry about the caps

[Alberta50fordor]

has anyone adapted the ford intake manifold to fit that carb? those mercury manifolds seems to be few and far between up here

[47topless]

delete

[tubman]

Originally Posted by Alberta50fordor

has anyone adapted the ford intake manifold to fit that carb? those mercury manifolds seems to be few and far between up here

There are 3 to 4 bolt adapters available, but the problem is the throttle bore size. I've never tried to bore a 3 bolt manifold, but I believe "Ol' Ron" on here has, and I believe that when you go to the full 1 7/16", it breaks through into the carb heat chamber. I think they got by that by boring it oversize and using thin sleeves.

EDIT : Here's a picture of a 3 to 4 adapter I got from Speedway Motors. I added a divide plate and it ran better than without it.

[Fortunateson]

Please correct me if I’m wrong...I just used the VanPelts table to calculate cubic inches on a stock ‘49 Merc engine with a 0.03 overbore and got 260.18 cu. so how did you come up with 275 cu?

[Gene1949]

Ideally, a 4bbl (small pattern 4GC or similar) and a mechanical advance distributor with a vacuum advance can using manifold vacuum is by far the simplest and most reliable setup. Parts are readily available for both.
The primaries are same size (15/16") as the Stromberg giving you bottom end throttle response (cruising) and an air valve controlled secondary for high RPM CFM.
Old skool 3 deuces give you 3x the headaches. I sold mine complete years ago for that very reason. Besides, if you are going that route you are going to have to use a mechanical advance distributor anyway.
Granted, a 4 bbl doesn't have the "kool factor" but how kool is it sitting in
the shop waiting on parts from less than reliable suppliers?

[cadillac512]

Originally Posted by Fortunateson

Please correct me if I’m wrong...I just used the VanPelts table to calculate cubic inches on a stock ‘49 Merc engine with a 0.03 overbore and got 260.18 cu. so how did you come up with 275 cu?

That's because it's been bored to 3 5/16" + .030". That makes the bore size 3.3425"





Terry

[tubman]

Originally Posted by Gene1949

Ideally, a 4bbl (small pattern 4GC or similar) and a mechanical advance distributor with a vacuum advance can using manifold vacuum is by far the simplest and most reliable setup. Parts are readily available for both....

True to an extant. A 2G is a lot simpler than a 4G simply because it's a two barrel. One will flow twice what a 94 or 97 will, which is plenty. To me, the biggest factor is cost. Have you priced a small base 4G lately? (If you can even find one.) And Merc manifolds are a lot cheaper than aftermarket 4 BBL units. I had a 390 Holley on an Offenhauser manifold on my '36 and liked it a lot. However, that combination would cost between $1500 and $2000 these days unless you're a real good scrounger (and lucky).

[Gene1949]

Unfortunately, true on all accounts Tubman.

[Fortunateson]

Originally Posted by cadillac512

That's because it's been bored to 3 5/16" + .030". That makes the bore size 3.3425"





Terry

Thanks for the correction.

[Ol' Ron]

Yes, boring out a stock Ford intake manufold will probably break into the exhaust passage. However, Bell mouthing the intake to match the 2GC may limit flow, this is a street engine and how often do you run at WOT. I too consider the cost of thes projects and unless your running at Bivell Mox Nix.
Gramps

[Alberta50fordor]

Originally Posted by tubman

There are 3 to 4 bolt adapters available, but the problem is the throttle bore size. I've never tried to bore a 3 bolt manifold, but I believe "Ol' Ron" on here has, and I believe that when you go to the full 1 7/16", it breaks through into the carb heat chamber. I think they got by that by boring it oversize and using thin sleeves.

EDIT : Here's a picture of a 3 to 4 adapter I got from Speedway Motors. I added a divide plate and it ran better than without it.

Would you recommend the adapter route? These are the carbs that came with our 55 bel air and 265 (in pieces)

[Alberta50fordor]

Also, a guy that I’ve been talking to in calgary that builds flatheads, race and street engines has an isky 3/4 max 1 that he recommends, what’re your guy’s thoughts on this cam in this engine vs the ford eab cam?

[Alberta50fordor]

I also have Sanderson headers in the car now with 2” all the way back with glass packs, not that these engines can move much air but I got a good deal on them so that’s what I’ve got

[28fordroadster]

I was going to ask about those 3 bolt to 4 bolt adapters, Thanks for bringing them up in this thread. Tubman and ol ron you guys know your stuff. What a great thread! I have scrounged a 4 bolt merc intake and a bubba's chevy distributor. I can't wait to try them.
Gramps... what's happening with that perfect engine build thread?

[Ol' Ron]

I don't use an adapter. Just fill theOS vacuun port with JB weld and drill the third hole. Alittle filing to the front holes will drop right on. Most problems can be solved with money, but thinking is much cheaper when you don't have any!!

[tubman]

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Originally Posted by Ol' Ron

I don't use an adapter. Just fill theOS vacuun port with JB weld and drill the third hole. Alittle filing to the front holes will drop right on. Most problems can be solved with money, but thinking is much cheaper when you don't have any!!

So you end up using just three bolts to mount the 2G. Good thinking. I never would have thought of doing that. I started collecting Merc manifolds as soon as I found out that a 2G (small base) fit perfectly.

[Ol' Ron]

Yes the merc intake is a better option , as it can be bored to the right size. Unfortunately, not everybody is that luckily.
G

[Alberta50fordor]

Originally Posted by Alberta50fordor

Also, a guy that I’ve been talking to in calgary that builds flatheads, race and street engines has an isky 3/4 max 1 that he recommends, what’re your guy’s thoughts on this cam in this engine vs the ford eab cam?

Reading a previous post about that cam it’s good for stock displacement engines, how would it do in a 272?

[Alberta50fordor]

Are these 8cm heads any different than the 8ba heads?

[tubman]

Yep. larger chambers. For some reason, Ford Motor Company decided to keep the compression ratio the same for Fords and Mercury's (which have larger a cylinder volume because of the longer stroke), so they made the chambers larger to keep the C/R equal. They are more like an 8RT head.

[Alberta50fordor]

Originally Posted by tubman

Yep. larger chambers. For some reason, Ford Motor Company decided to keep the compression ratio the same for Fords and Mercury's (which have larger a cylinder volume because of the longer stroke), so they made the chambers larger to keep the C/R equal. They are more like an 8RT head.

So a good combo is the merc stroke with ford heads?

[flatford8]

Yes EAB Ford heads……but you still need to check the amount of “squish”….Mark

[Ken Henry]

The Max-1 will make more power sacrificing low rpm torque. The book Flathead facts has nice dyno results. I think it is worth it… There is more lift so valve clearance needs checking.

[tubman]

This is a always a good reference : https://www.tildentechnologies.com/C...rformance.html. It shows a stock 8BA cam to have a lift of .307", an Isky MAX-1 to have .350", and an 8CM comes in at .337" (unfortunately, there are no specs for EAB, although I would expect it to be similar to the 8CM). Thus you can see that an 8CM (and probably an EAB) are a significant upgrade over the stock 8BA cam, approaching the MAX-1 in lift. When I did the Merc in my '51 club coupe, I had a new MAX-1 cam and kit I was going to use, but after some thought and discussions here and on the H.A.M.B., I decided to keep the 8CM. The way the car performs, I think it was the right decision.

I used the MAX-1 in a 258" engine for the "T" tub I am building. I figured it was better in an 1800 lb car than one the weighs in at a hefty 3200.

[Alberta50fordor]

Originally Posted by tubman

This is a always a good reference : https://www.tildentechnologies.com/C...rformance.html. It shows a stock 8BA cam to have a lift of .307", an Isky MAX-1 to have .350", and an 8CM comes in at .337" (unfortunately, there are no specs for EAB, although I would expect it to be similar to the 8CM). Thus you can see that an 8CM (and probably an EAB) are a significant upgrade over the stock 8BA cam, approaching the MAX-1 in lift. When I did the Merc in my '51 club coupe, I had a new MAX-1 cam and kit I was going to use, but after some thought and discussions here and on the H.A.M.B., I decided to keep the 8CM. The way the car performs, I think it was the right decision.

I used the MAX-1 in a 258" engine for the "T" tub I am building. I figured it was better in an 1800 lb car than one the weighs in at a hefty 3200.

Found a post on the H.A.M.B about the eab cam, .328 supposedly so if that’s true it’s not far off from the 8cm
https://www.jalopyjournal.com/forum/...ab-cam.398204/

[Ol' Ron]

Anyone rebuilding a flathead should get a copy of JWL's book. This can save you a great deal of mone and get a better engine for the money you do spend. Max VP has them. And you;ll help his widow.
Gramps

[miniceptor86]

Excuse my ignorance. What is JWL’s book?

[miniceptor86]

Oh and I guess I’m one of the lucky ones. I scored this Merc manifold, bored it out with a drill press and hole saw followed up with a sanding drum in a hand drill.

https://www.fordbarn.com/forum/pictu...ictureid=45339

[Ken Henry]

Flathead Facts. Excellent reading

[miniceptor86]

Thanks.

[V8COOPMAN]

Originally Posted by miniceptor86

Excuse my ignorance. What is JWL’s book?

"JWL" is John W. Lawson, a most-knowledgeable and experienced flathead guy, whom unfortunately, we just lost this past year. You can get the book at Amazon, or at Mac VanPelt's site. This is THE flathead book!

Coop

[miniceptor86]

Flathead Facts is no longer available on Amazon.

[Alberta50fordor]

Ok so far here’s the plan/build
C1ba(8ba) block, 4”crank, 3 5/16 pistons .030 over, EAB-A camshaft(not sure what the “A” stands for), ford 8ba aluminum heads, (I have one eab head lying around but could never find the other side), adjustable lifters, stock ford intake(for now), stock distributer(for now), looks like I can rob an aluminum cam gear from one of my other engines
Anything I’m forgetting? Il be checking the piston to head clearance tonight

[Ol' Ron]

This gives 280 Pus ci. I have the same engine in my truck, along with the EAB cam as well, Intake is a merc with 2GC carb and a chevy distributor. Rear axle is a spicer 44 with 3.73 gears and posi. Trans is a T170 with 3 spd OD In a 47 Int KB1 Took the truck to the Weston, Andover hill in VT and drove the truck up in OD to the top of this 14% Maintaining 50 MPH. Unfortunately, The speed droped to 43 MPH over the top engine was turning 1300 RPM The torque of this engine is un believable. Truck is fore sale
Gramps

[Alberta50fordor]

Originally Posted by Ol' Ron

This gives 280 Pus ci. I have the same engine in my truck, along with the EAB cam as well, Intake is a merc with 2GC carb and a chevy distributor. Rear axle is a spicer 44 with 3.73 gears and posi. Trans is a T170 with 3 spd OD In a 47 Int KB1 Took the truck to the Weston, Andover hill in VT and drove the truck up in OD to the top of this 14% Maintaining 50 MPH. Unfortunately, The speed droped to 43 MPH over the top engine was turning 1300 RPM The torque of this engine is un believable. Truck is fore sale
Gramps

And for a driver torque is more desirable than hp?

[V8COOPMAN]

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Originally Posted by Alberta50fordor

And for a driver torque is more desirable than hp?

Oh YEAH! Torque is the force that makes your face look pleasingly-funny as you get on it. In other words, torque is what causes your butt to be plastered into the seat as you accelerate through the gears.

Coop

.

[tubman]

It is known that Torque and Horsepower are always equal at 5252 RPM. Given that even a reasonably modified flathead will never approach the RPM, what do you think?

Real Racers need not respond; That's a completely different set of circumstances.

[Alberta50fordor]

pulled a piston out and found the rod bearings to be the floating style(one bearing for two rods) is this good or bad? connecting rod journals have two oil holes, short skirt(for a flathead) 3 ring pistons

[miniceptor86]

Originally Posted by tubman

It is known that Torque and Horsepower are always equal at 5252 RPM. Given that even a reasonably modified flathead will never approach the RPM, what do you think?

Real Racers need not respond; That's a completely different set of circumstances.

Horsepower was an early sales gimmick so that prospective buyers of steam power could relate the the steam engine’s power to the familiar horse.

[Ken Henry]

Torque without engine speed is useless. I can apply whatever you want with my arm and a long enough bar. Physics tells us that power moves and accelerates things including our Fords.

[JayChicago]

Originally Posted by tubman

It is known that Torque and Horsepower are always equal at 5252 RPM.

Whaaat?! Never heard that before. Please explain.

[tubman]

Originally Posted by JayChicago

Whaaat?! Never heard that before. Please explain.

As "miniceptor86" said in an earlier post : "Horsepower was an early sales gimmick so that prospective buyers of steam power could relate the the steam engine’s power to the familiar horse." Horsepower is an extrapolation from the torque reading, calculated by a formula. Since it is a merely a calculation, there is always one value where it will be equal.

[V8COOPMAN]

Originally Posted by JayChicago

Whaaat?! Never heard that before. Please explain.

Jay.... You MAY need to watch this vid a couple of times for it to sink-in, but this kid explains it fairly well. DON'T let yourself get hung-up on "5,252 RPMs". Click the link BELOW!

Coop


https://youtu.be/lt7iUBE3_AE

.

[Roger/Sacramento]

In my 41 Pickup with a 4 speed tranny I have a late block 276 CID with an L100 cam, 3-97's, Offie heads and crab ignition. It runs great with good pull thru the gears. Drive it around town often. I wouldn't change a thing.

[JayChicago]

Tubman & Coopman
Thanks for the explanations. I learned something. I get the 5252 RPMs isn't meaningful, is just a number-crunching value in the formula. What is meaningful is: "Horsepower is an extrapolation from the torque reading, calculated by a formula." I did not know that.

[Ol' Ron]

When building an engine, consider the application. This usually cost less, and gives better gas mileage.
Gramps

[Alberta50fordor]

Originally Posted by Ol' Ron

This gives 280 Pus ci. I have the same engine in my truck, along with the EAB cam as well, Intake is a merc with 2GC carb and a chevy distributor. Rear axle is a spicer 44 with 3.73 gears and posi. Trans is a T170 with 3 spd OD In a 47 Int KB1 Took the truck to the Weston, Andover hill in VT and drove the truck up in OD to the top of this 14% Maintaining 50 MPH. Unfortunately, The speed droped to 43 MPH over the top engine was turning 1300 RPM The torque of this engine is un believable. Truck is fore sale
Gramps

What air cleaner do you guys run on the 2GC? I'm considering trying that carb with merc intake out first(i lucked out and found an aluminum merc intake at a swap meet) is there anything else I need to look for/modify? how do you have your throttle linkage set up? I just put in a stromberg e-fire distributor the other night so ignition system is covered does anyone make a phenolic spacer for the chevy carb or have you guys found those ones don't boil as bad?

[tubman]

I use this unit from Speedway Motors or Amazon. On the chance that it might be restrictive, I ordered another element and made a longer center stud and run two elements stacked one on top of the other. It looks good, works good, and still fits under the hood of my '51 with good clearance. (Sorry about using a link rather than a picture; for some reason I can't attach a 250K .jpg this morning after doing it successfully for years.)

https://www.amazon.com/Inch-Chrome-C.../dp/B075NQR3M4

[scicala]

Originally Posted by jimvette59

FYI, I have a 67 327 300 hp SBC with a wcfb that the primaries are 15/16 the same size as a 94

The last production 327/300 small block Chevy was in '66, and they came with Cater AFB carbs since the first one in '62.
I assume your '67 had come parts swapped.

Sal

[Alberta50fordor]

Originally Posted by tubman

I use this unit from Speedway Motors or Amazon. On the chance that it might be restrictive, I ordered another element and made a longer center stud and run two elements stacked one on top of the other. It looks good, works good, and still fits under the hood of my '51 with good clearance. (Sorry about using a link rather than a picture; for some reason I can't attach a 250K .jpg this morning after doing it successfully for years.)

https://www.amazon.com/Inch-Chrome-C.../dp/B075NQR3M4

sweet thanks, i should've taken you up on your offer a while back about going into detail about your set up, what do you have for throttle linkage? how did you bore the intake out? just a die grinder or something more precise?

[tubman]

Originally Posted by Alberta50fordor

sweet thanks, i should've taken you up on your offer a while back about going into detail about your set up, what do you have for throttle linkage? how did you bore the intake out? just a die grinder or something more precise?

Basically, I just added a ball stud to the 2G that was the same size as the end of the Ford throttle rod, and everything fell together. IIRC, I cut off the end of the Ford throttle rod, threaded it and screwed on an adjustable rod end. Actually the throttle doesn't open quite all of the way, but the increase in performance was enough that I haven't got around to fixing that yet.

I used something called a "Rota-Broach" and a guide I made out of 1" thick aluminum to bore the manifold. I just slip the guide over the carburetor studs, clamp the intake manifold on to my drill press, and bore away. The only tricky part is getting the manifold clamped down at just the right angle because the carb mounting surface is not parallel to the block mounting surface. I have done aluminum and cast iron manifolds and they both cut easily. This method allows you to cut all the way down the manifold a full 1 7/16". When this is done, I use a die grinder to smooth the transition at the bottom of the bore. The "Rota-Broach" and it's required arbor are kind of expensive, but I use the in the manufacture of my "trash can" condensers. I have the cutter and an extra arbor I could let you use (along with the guide) for the cost of shipping if you want. All I would need is a $100 deposit to make sure I get it back. PM me if you're interested.

EDIT : One last thing. The 2G base has voids cast into it for manifold heat. The size and shape of the Merc manifold carb mounting surface is such that these voids can cause vacuum leaks. This can be remedied by using stacked Merc and Rochester carb gaskets. In the alternative, I have made block off plates made from 1/16" aluminum to take care of this. Since it costs as much to make 20 of these as 1, I have spares.

I notice you are in Canada, which may make shipping problematic.

[V8COOPMAN]

Originally Posted by tubman

I use this unit from Speedway Motors or Amazon. On the chance that it might be restrictive, I ordered another element and made a longer center stud and run two elements stacked one on top of the other. It looks good, works good, and still fits under the hood of my '51 with good clearance. (Sorry about using a link rather than a picture; for some reason I can't attach a 250K .jpg this morning after doing it successfully for years.)

https://www.amazon.com/Inch-Chrome-C.../dp/B075NQR3M4

How's this, for a dumb boy?

Coop

[tubman]

That's the one.

Thanks, Coop.

[Alberta50fordor]

Originally Posted by tubman

Basically, I just added a ball stud to the 2G that was the same size as the end of the Ford throttle rod, and everything fell together. IIRC, I cut off the end of the Ford throttle rod, threaded it and screwed on an adjustable rod end. Actually the throttle doesn't open quite all of the way, but the increase in performance was enough that I haven't got around to fixing that yet.

I used something called a "Rota-Broach" and a guide I made out of 1" thick aluminum to bore the manifold. I just slip the guide over the carburetor studs, clamp the intake manifold on to my drill press, and bore away. The only tricky part is getting the manifold clamped down at just the right angle because the carb mounting surface is not parallel to the block mounting surface. I have done aluminum and cast iron manifolds and they both cut easily. This method allows you to cut all the way down the manifold a full 1 7/16". When this is done, I use a die grinder to smooth the transition at the bottom of the bore. The "Rota-Broach" and it's required arbor are kind of expensive, but I use the in the manufacture of my "trash can" condensers. I have the cutter and an extra arbor I could let you use (along with the guide) for the cost of shipping if you want. All I would need is a $100 deposit to make sure I get it back. PM me if you're interested.

EDIT : One last thing. The 2G base has voids cast into it for manifold heat. The size and shape of the Merc manifold carb mounting surface is such that these voids can cause vacuum leaks. This can be remedied by using stacked Merc and Rochester carb gaskets. In the alternative, I have made block off plates made from 1/16" aluminum to take care of this. Since it costs as much to make 20 of these as 1, I have spares.

I notice you are in Canada, which may make shipping problematic.

So the performance increase is noticeable with the bigger 2bbl?, how does it compare flow/performance wise to a super dual?
also how do you have your choke set up? I'd rather stick with a manual choke

[Ross F-1]

From various sources:
Holley 94. Carb. 155 cfm
Holley 8ba. Carb. 162 cfm
Holley ECG (2110 Y-block) 210 cfm
Rochester 1 1/4" flange ("small base"), 1 7/16 Bore x 1 3/32 venturi = 278 CFM.

[tubman]

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Originally Posted by Alberta50fordor

So the performance increase is noticeable with the bigger 2bbl?, how does it compare flow/performance wise to a super dual?
also how do you have your choke set up? I'd rather stick with a manual choke

It's really hard for me to say. The 2GC is on a good running '51 Merc with massaged Edmunds heads and a Mallory dual point that I swapped in to replace a rather tired stock 8BA. The 8BA ran fine but was always a little weak. I tested the compression before I pulled it and all cylinders were between 85 and 105 psi. The Merc I put in, though used, had 110-115 on all 8. The increase in performance was quite evident.

As to the difference (if any) from a "Super" dual, I really have no idea. If I had to guess, I'd say that the "Super" would have a slight advantage at speed but would be more difficult to get and keep running right. As I alluded to earlier, there is still a little throttle left on my present set up due to the geometry of the linkage. I adjusted the linkage to get full throttle, which resulted in obtaining a full pull at the penalty of a 1500 RPM idle. The increase was not enough to cause me to upgrade the throttle linkage (yet). I think, given the fact that I have a stock cam, ports, and displacement, the 2G is about all the carburetor my engine will take.

I have been a manual choke guy all my life, but the Mercury choke mechanism matched so well with the 2G that it was just too good to ignore. When run backwards, the fuel line and throttle linkage need very little change. The choke however, ends up on the wrong side and pulls backwards and is just located awkwardly. I have done 2G setups with both "regular" (choke mechanism on the carburetor) and "divorced" (choke mechanism located on the manifold) chokes, and all that is needed in either case is a slight bending and shortening of the tube or acuating rod. As a side benefit, I have now learned how to repair and adjust automatic chokes and have come to love them.