recommendations for a little more hp & torque?

[mumpsimus]

My 37 could use a little more torque and hp when hauling the family around. It is a stock 21 stud, with rebuilt carb, distributor, and fuel pump. I don't want a hot rod or loud pipes, and don't want to pull the motor from the car. It idles well, is quiet and runs smooth. I'd like to keep all that, but with a touch more oomph when I step on the accelerator pedal. If it could go up from the stock 85hp to say 105hp that would be nice.

What do you guys recommend? Simply mill the heads for higher compression? Or buy aluminum heads, or instead buy dual carbs, or a cam, or something else?

Is any modification recommended over the others?

thanks in advance,
Pete

[JSeery]

Might want to look at JWLs book, it addresses this very topic. He goes through a series of bolt-on modifications and then more in-depth mods and shows the dyno results with each.

[mumpsimus]

Thanks! I'll see if I can find a copy.

Originally Posted by JSeery

Might want to look at JWLs book, it addresses this very topic. He goes through a series of bolt-on modifications and then more in-depth mods and shows the dyno results with each.

[deuce_roadster]

Really, the best thing you could do is increase the stroke, but that involves a different crank and pistons. Not sure the bolt on stuff will get you to the HP level you want.
Good luck!

[bigdoor]

you are asking for a hot rod

[mumpsimus]

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I don't want to bother with stroking it. But how much power would the bolt-ons add? If not 20hp, will they just give 5-10hp then? That doesn't seem like much, but I guess it might be worth the effort and cost.

[mumpsimus]

Originally Posted by bigdoor

you are asking for a hot rod

I don't want a hot rod. The car is all stock and I want to keep it mostly that way. I just want a little bit more hp than stock. Do you have any recommendations for a few hp from a 21 stud motor?

[petehoovie]

What is the ratio of the rear end your car has?....

[Charlie ny]

Cheapest route to more HP is to raise the compression and with a flathead headers and
dual exhaust are a good idea......quiet mufflers if you wish. Take a comp test first.....
if you see some cylinders under 85 pounds you'll be wasting $$$$ to do any mods.
Charlie ny

[Floyd]

A very basic question would be- What is the actual condition of your motor that you are saying is "stock"? Do you have experience with a properly built stock motor that is really tuned up and running healthy? The reason I say this is there is a very wide range of performance difference between a weak ,poorly tuned motor and a well tuned healthy one. Both of them may run quiet, smooth and not make smoke, but actual performance may vary widely. Since we are not dealing with a lot of horsepower with these old flatheads, a minor horsepower increase from tuning can make a big difference in seat of the pants performance.
If the iginition system is really setup correctly, the carb is truly correct, the rings are tight , the piston to head clearance is set to Ol'Ron's specs , compression is good and even ,cam not worn out, valves adjusted and sealing properly, etc then the engine will perform as a strong, nimble and tight power plant, especially with the light Ford bodies (21 stud era). I would say that 75 percent of the engines out there running today are nowhere near the state of optimum tune. This is shown in the numerous complaints of poor milage, hard starting, overheating, etc. Find a friend that has a really good healthy stock 21 stud motor and compare how his performs before you go into tearing into and changing yours. My 21 stud LB motor, newly done, really performs with spirit when pulling around a light 32.
My opinion

[texas webb]

Originally Posted by mumpsimus

Thanks! I'll see if I can find a copy.

You can get JWL's book from him or Van Pelts sales.

[mumpsimus]

Originally Posted by Charlie ny

Cheapest route to more HP is to raise the compression and with a flathead headers and
dual exhaust are a good idea......quiet mufflers if you wish. Take a comp test first.....
if you see some cylinders under 85 pounds you'll be wasting $$$$ to do any mods.
Charlie ny

Thanks for the reply. Good tips. I’ll double check compression in all 8 before going further. Milling the stock heads seems like a simple route. Not sure if finding 21 stud aluminum heads is any better than milled iron heads.


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[mumpsimus]

Originally Posted by Floyd

A very basic question would be- What is the actual condition of your motor that you are saying is "stock"? Do you have experience with a properly built stock motor that is really tuned up and running healthy? The reason I say this is there is a very wide range of performance difference between a weak ,poorly tuned motor and a well tuned healthy one. Both of them may run quiet, smooth and not make smoke, but actual performance may vary widely. Since we are not dealing with a lot of horsepower with these old flatheads, a minor horsepower increase from tuning can make a big difference in seat of the pants performance.
If the iginition system is really setup correctly, the carb is truly correct, the rings are tight , the piston to head clearance is set to Ol'Ron's specs , compression is good and even ,cam not worn out, valves adjusted and sealing properly, etc then the engine will perform as a strong, nimble and tight power plant, especially with the light Ford bodies (21 stud era). I would say that 75 percent of the engines out there running today are nowhere near the state of optimum tune. This is shown in the numerous complaints of poor milage, hard starting, overheating, etc. Find a friend that has a really good healthy stock 21 stud motor and compare how his performs before you go into tearing into and changing yours. My 21 stud LB motor, newly done, really performs with spirit when pulling around a light 32.
My opinion

Thanks Floyd. I’m pulling a heavy load: woodie body, 5-6 passengers and sometimes a light trailer and one or two c1915 motorcycles. A bit more mass than a light 32. The motor was rebuilt to stock specs by the previous owner 5k miles ago. I’ve done the dizzy, carb, HT leads, etc this summer. Assuming (big assumption, I know) that the motor was running as well as it was designed to do, would you recommend a cam swap or aftermarket heads? Or is milling stock heads recommended? I’m not convinced that additional carbs are beneficial unless other changes are done first. But I’m open to suggestions.

This is my first Ford V8, but I’ve built and tuned a lot of 1-2 cylinder bike motors from 1910-WWII. Small changes are very beneficial in those 5-20hp motors! But it is much easier to port them, valve jobs, etc than on a V8 that is still in the car. I don’t want to pull it out, hence my questions about simple bolt-ons. Thanks again.


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[Lanny]

[QUOTE=mumpsimus;1541896]Thanks for the reply. Good tips. I’ll double check compression in all 8 before going further. Milling the stock heads seems like a simple route. Not sure if finding 21 stud aluminum heads is any better than milled iron heads.

================================================== ========



Before checking the compression, run the engine for 10 minuets or so,
and then pull all the spark plugs out, and open the carb throttle
plates wide open so the cylinders can suck in plenty of air as you're
checking compression.






.

[40 Deluxe]

Forget about changing the cam. That would make your car into a 'hot rod'! You would lose power at normal, everyday RPM. Same with dual carbs. Only good at full throttle at high RPM.
How about a McCullough supercharger? They came out in 1937 to solve your exact problem. One of these would give the needed power and would be period correct, to boot!

[Brian]

As much as I love 21 stud engines, in all honesty, the easiest and cheapest method to achieve what you desire, would be to drop in a 39-48 239 cu in engine. Bolt in deal!!

[flatheadmurre]

Originally Posted by Brian

As much as I love 21 stud engines, in all honesty, the easiest and cheapest method to achieve what you desire, would be to drop in a 39-48 239 cu in engine. Bolt in deal!!

That bolt in deal takes a lot of money...lol
Will be cheaper to punch out the engine to 3 3/16 and raising the compression then finding a new engine that you know is good.

[48fordnut]

Gear ratio ,and raise the compression. You are pretty heavy for a small eng.

[Lawrie]

In our 33 fordor , we tow a caravan ,with the 221 babbit engine it was Ok and will do a 5000klm trip no worries,but if you got caught out rubbernecking at something and never saw a hill coming it was drone along and wait.
I had built up a 99a engine with a 4in crank ,stock cast iron heads ,stock 33 manifold and 97 crab,and fitted it this is a way nicer engine.
Not cheap but sure nicer to drive,
If we never did towing,but just touring in the 33 I would have left the 221 babbit engine in as they are so nice ,
Lawrie

[tubman]

Just "milling the heads" for more compression is an oversimplification. You want to end up with .040-.060" squish in the combustion chambers for the greatest efficiency. This entails removing the heads and checking the existing clearance with clay or aluminum foil balls. Once you know where you're starting from, you can determine how much to mill. I always take a liiiitle bit more off than I should and use a die grinder to remove any remaining areas of interference. You can do this with stock heads as well as aftermarket aluminum heads. As to aftermarket heads : good luck in finding some, and if you do find them, they most likely will have been worked over, probably several times. Don't assume that just bolting them on will result in a satisfactory situation. Any heads you use will need to be massaged. I would also suggest going with a larger 2 BBL carburetor, either a Ford 2100 series or maybe even a Rochester 2GC.

Unless you are into pulling the engine and getting serious with internal modifications, this is about all that you can do. I am assuming here that the stock ignition is "up to snuff".

[Bored&Stroked]

Assuming the engine is in good shape, correctly tuned, etc.. - there are a few things you can do, but you definitely won't pickup 30 HP doing them.

You can surely try the "milling the heads" deal - is fairly inexpensive as compared to all other options. I would review the exhaust system - putting a good set of headers on it will help and if you decide to go further (like a different engine), the system will be a bolt-on to the newer engine (so you won't waste the time/effort/$$$ in trying this approach).

Taking it further . . . For a heavy car - you need more torque . . . and the best way to get more of that is with more cubic inches. As some mentioned, putting a later 59AB style engine in it would be a definite improvement (even a stock one). All the parts you have will bolt-up to it and it is a "drop in" type of situation. With that said, having the correct manifold, carb, distributor, fuel pump, etc -- off of the 59AB is probably the best situation. I'm not sure of the generator/fan mount on a 37 - my guess is that you'll use what you have. The water pumps are the same - so everything should slip right in.

Now - if you want to take it further - having a 59AB with a later 4" Mercury crank (and correct pistons, etc) will give you 255 cubic inches and more torque to boot. If you are going this route, then you're pretty much finding/building a completely new engine - or buying one. This '255' would be a much better engine than what you have today (performance wise) . . . and again, since it is a 59AB style engine - everything bolts right up.

BUT - it is always a situation of money and time - and always 2 - 3 times what you think of both of them! LOL

Good luck and enjoy your Ford!

B&S

[keith oh]

The simplest and most economical way to go is change to a 411 rear end. That little 21 bolt engine will pull any passenger load you put in her. There are lots of 411 gear sets around at a very reasonable price. Of course the gas mileage will drop down to 12 to 14 mpg but you sure can buy a lot of gas for the thousands of dollars doing the suggested fixes.

[rotorwrench]

One of the Tex Smith Flathead books (paperback) has an article about beefing up a 21 stud motor for a 1935 Ford coupe to run in the Great American Race. They didn't want a hot rod but there are only two ways to get a 21 stud motor to have 1950s type power, larger displacement and/or a two speed rear axle (Columbia Overdrive). The GAR generally wants a stock type motor so blowers and exhaust mods are not used. They chose a 37/38 type 21 stud because it is the best of the 21-stud for reliability but they wanted the water pump in head set up so they had to use the block off plates. They turned a 221 CID motor into a 255 motor by going through all the trouble to install a 4-inch stroke Mercury crankshaft and boring the thing out for 3 3/16" bore sleeves. They had to bore through the cylinder walls to get the big bore sleeves in there but they wanted uniform thickness cylinder walls for best cooling and reliability. They used epoxy to install the sleeves to keep the block structure a bit stiffer.

I think they also had a Columbia Overdrive but I'm not sure. This car finished the GAR with no problems and got up over mountains with a lot less difficulty than a 221 would have had. I don't propose that you do all this but you might consider a Columbia overdrive rear axle. The later wider ones for 42 through 48 are easier to find than the early ones and some have been modified to narrow down the one side to work with the 37 through 41 type axles.The Mitchel overdrive might also be something to consider.

[scicala]

Originally Posted by bigdoor

you are asking for a hot rod

I wouldn't exactly say 100 total HP tops with a smooth idle is a hot rod.

Sal

[Bored&Stroked]

Going to a 4.11 rear will allow you to pull the car better - with the engine you have, but it isn't much fun if you want to go over about 55 MPH for any stretch of time. You end up with a lot of engine revs at the faster highway speeds . . . I know this well in that my 32 Ford has the original 4.11 and I have a very stout flathead. I've got plenty of power, but am putting a Columbia in it - for 70 MPH freeway speeds.

Also, you need enough torque to pull the Columbia if you're in a heavy car and are in hilly country. Your little 221 probably won't have enough grunt to pull it up any sort of hill (given your heavy car, number of passengers, etc).

Me - I'd try a few things with what you have (starting with checking it's condition) - then make a determination if you can "tweak" what you have . . . or go for a bigger/later engine . . .

[40 Deluxe]

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I see several recommendations for headers, but actual tests have shown that headers are of little or no value, especially on a stock engine. Since Mumpsimus has said he doesn't want to pull the engine, a lot of suggestions miss the mark. After milling the heads to get the proper squish clearances, the simplest, most effective bolt-on would be a supercharger with mild boost. Probably cost effective, too. As I remember, the McCullough supercharger of the '30's was marketed (at least in part) to traveling salesmen who carried heavy samples and needed a little more oomph to get to the next prospect.

[Ol' Ron]

First, het a copy of JWL's book. He has all the dyno results of the stock engine amd all the mods. I realize you have a 21 stud engine and he's using a 239. the results wii amaze you. The next thing is to get a good tune on the engine. Ignition advance and AF readings at cruise and WOT. The simplest modification you can make is to mill the heads for .045/.050" piston to head clearance. This will increase the quench area of the combustion chamber, thus burning more of the fuel. Increases econmy as well as preformance. Not much else you can do to a 21 stud engine, except make it bigger. Good luck.

[JSeery]

I agree that headers on a flathead are mainly for looks and not performance. Same goes for dual exhaust. I'm a fan of both, but they are not going to help you much performance wise. Like Ol Ron posted, the biggest improvement is going to be getting the .045/.050 piston to head clearance. Fairly cheap but a little labor intensive to get it correct, it should be well worth the effort.

[mumpsimus]

Thanks guys! Lots of good stuff came through in the thread over the weekend! I'll start with the heads, and maybe a slightly larger carb. The McCullough blower sounds great, but expensive and maybe hard to find? I'll look around. A later/larger motor is the obvious thing to do, but I like keeping the original motor in the car. The whole car is pretty original, and I like it that way. I'll call Mitchell and find out more about their overdrive, and maybe go with 4.11 gears in the rear at the same time.

I drive the car like an old man, and don't need to go fast or spin tires or anything like that. So just a bit more torque is what I'm after. It does OK on the hills of San Francisco, but I do choose which hills to climb and which ones to go around!

thanks again.
Pete

[mumpsimus]

Trying to post a photo. Hopefully it works this time.

[Ron Pilger]

Gorgeous example of automotive history. What a treat to see. Me and many others, i suspect, would love to have this ride inside our garage, regardless of HP level or torque available.

[mumpsimus]

Thanks Ron. I'm very happy with the car. The only downside is that there are so many more parts to service/repair on a car versus an old motorbike!

Originally Posted by Ron Pilger

Gorgeous example of automotive history. What a treat to see. Me and many others, i suspect, would love to have this ride inside our garage, regardless of HP level or torque available.

[Floyd]

That's a great car! Take good sensible care of it.

[rowens55]

Love the bikes! IN love with the car!! Beautiful!

[Bill OH]

I used a model 48 stromberg carb which has 1 1/32 inch vs 31/32 for the 97. I run a larger tail pipe such as 2", but you will have to go a glass pack muffler. Pick a 1/4 mile out in the country and see what the car will do in stock form and then add the larger tailpipe and try the same 1/4 mile again and then add the larger model 48 and see what that does. The two improvements should show something. Let's the engine breath better.. If you mill the heads. use an air grinder to smooth out the combustion chamber and make the transfer area deeper. That helps breathing. While you have the heads off, find TDC by putting socket over a stud held by nut, put a permanent pointer at the crank pulley, brng the piston up on # 1 until it hits the socket, mark the crank pulley at the pointer, the crank the opposite direction until the piston again hits the socket, mark the crank pulley opposite the pointer, then divided distance between the two marks and permanently make the crank pulley with a file and that is TDC. About 1/4 " in advance of the TDC is where you want #1 to fire. Check it with a timing light. You can also run a wire from the coil condenser connection about 8" up the spark plug wire loom, strip the wire back about 1/2., wade it up and put rosin core solder on it. You can connect a dwell tach to that wade of solder. You can also solder a flex wire to the top of the condenser and ground the other end to a coil mounting screw - if the ground bracket comes loose from the condenser you are not stuck along the road. Enjoy.

[Bill OH]

Another thought: Back out the vacuum brake adjustment screw easily until it stops. Let's the advance do better.

[rotorwrench]

I haven't been to Frisco for a while but I do remember those hills. Some are pretty steep too. A person might have to have that vacuum brake set a bit stiffer for those hills or it'll ping. It can be backed out then test driven on some moderate hills to see if it pings. If it does, just keep tightening the brake piston spring till the ping goes away or is at least minimized as much as possible. This is the OEM procedure for adjusting the vacuum brake to retard the advance a bit when pulling good. The earlier distributors didn't have as much advance as the ones made in 1941 & later. A lot of the old ones were retrofitted with that mechanism during service. Those need the brake a bit more than the early ones do. If a person ever takes the distributor apart, the advance mechanism will be clearly marked 11A if it has been retrofitted with that advance unit.

[slowforty]

Make the passengers go on a diet. Seriously the best thing you can do is make sure everything is in top condition. Dual exhaust is the cheapest thing to do. Dont waste money headers unless you do more modifications. The last statement was from a 1956 Hot Rod Article about Hopping a Flathead.

[jrvariel48]

Is that an Ariel on the trailer??!!

[Bill OH]

If you can get your 221 to ping in SF hills I will be suprised with 87 octane gas.

Very nice station wagon - do not see many of those - happy for you.

[Ford Freak]

Originally Posted by rowens55

Love the bikes! IN love with the car!! Beautiful!

^^^^What he said X 2 !!^^^^^^

[JSeery]

Very nice!

[buzz4041]

Great looking ride and bikes.

[drolston]

I don't have any dyno to prove it but a riser under the carb is supposed to improve torque in the mid to upper rpm range. I put 2" risers on my 3x2 Offy manifold, for looks and to make it possible to invert the progressive linkage. It might be worth a try for very low $$. After installing the riser, be sure the linkage from firewall to carb is still long enough to let the carb get to the idle stop. I had to fabricate an adjustable linkage.

If you do try it, maybe put a stop watch on throttle slam high gear acceleration from 40 to 60, before and after.

[JSeery]

In general an increase in the intake runner length shifts the torque to a higher rpm range. No increase in power, just a shift in rpm range.

[40 Deluxe]

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Originally Posted by JSeery

In general an increase in the intake runner length shifts the torque to a higher rpm range. No increase in power, just a shift in rpm range.

Uh, I've always read that longer intake runners shift the power band to a lower RPM range, not higher.

[flatheadmurre]

Short wide runners for high rew...long narrow for low rew.
Little more to it then just that to...the airflow hitting the valve when it closes causes a pulse that goes back into the runner.
You have to calculate the lenght to gain some effect of getting that pulse in the right place before the valve opens again.
And a long narrow runner reaches it´s maximum velocity pushing most air into the cylinder at a lower rew.
On top of that you have the plenum size to.

[mumpsimus]

Yes, that is my wife's 1936 Ariel Red Hunter. I built it for her from a basketcase (i'm not sure if that is a phrase used in the car world) --I bought a frame and forks in a basket, then had to source all other items. Built the crank, gearbox, laced the wheels, etc. That took me a while, but the bike has now done many thousands of miles in the past 15 years.

The ignition seems good. A local guy rebuilt the dizzy this summer for me. He backed off the timing retard screw so that it runs at full advance. I questioned him on that, but he said it runs best that way and then there is no issue with the timing accidentally being retarded. I've never heard the motor ping so far...

Originally Posted by jrvariel48

Is that an Ariel on the trailer??!!

[mumpsimus]

Thanks Tubman. The previous owner put a 91-99 carb in it (Ford/Holley model AA 1939-1941). I installed a rebuilt kit from Daytona Parts Co this summer. That helped a lot, as the old power valve was very dirty and sticking. I'll have to study the 91-99 versus the 2100 series. I can tell you all about motorcycle carbs from 80-100 years ago, but I'm just learning Ford stuff now.

Originally Posted by tubman

I would also suggest going with a larger 2 BBL carburetor, either a Ford 2100 series or maybe even a Rochester 2GC

[tubman]

If you're going for the later, larger Holley two barrel, I should have said 2110. Here's a link to a thread on the H.A.M.B. with a little more detail : https://www.jalopyjournal.com/forum/...thead.1017335/. After reading the thread on Stromberg 48 rebuilding costs, this is probably a good way to go.

[JSeery]

Originally Posted by 40 Deluxe

Uh, I've always read that longer intake runners shift the power band to a lower RPM range, not higher.

You are correct, posted it backwards!

[Bored&Stroked]

The 3-bolt flange version of the Holley 2110 is a great carb - and it will bolt right onto the Stromberg style intake flange. These carbs were used on a few different Fords around 1956 - 1957 or so (going from memory here). The three-bolt version from the 50's flows about 210 CFM.

The throttle plates are larger (seems to me they're around 1 1/32??? - so you should port the top of the intake to match the throttle bores of the 2110. If you don't do this, I really don't see much advantage in trying to use them.

[40 Deluxe]

Originally Posted by Bored&Stroked

The 3-bolt flange version of the Holley 2110 is a great carb - and it will bolt right onto the Stromberg style intake flange. These carbs were used on a few different Fords around 1956 - 1957 or so (going from memory here). The three-bolt version from the 50's flows about 210 CFM.

The throttle plates are larger (seems to me they're around 1 1/32??? - so you should port the top of the intake to match the throttle bores of the 2110. If you don't do this, I really don't see much advantage in trying to use them.

That 2110 is for a 292 engine so might be a mite big for a 221. You might have to wind up that 221 in second to get any more power. At normal cruising speed, I doubt you would see any advantage.

[Lawrie]

Surely the larger carb would only come into play at higher RPMs,my 33 has a 265ci 99a engine,stock 33 cam and valves,stock 33manifold and 97 carb,stock exh manifolds and single exhuast,and it works great up to about 65 mph,this with a 3,78 rear,it will go way faster but doesnt seem as nice over that,
Am I missing some HP or something with the small carb,sure, but I dont need to be going over 60-65.
Lawrie

[jrvariel48]

Originally Posted by mumpsimus

Yes, that is my wife's 1936 Ariel Red Hunter. I built it for her from a basketcase (i'm not sure if that is a phrase used in the car world) --I bought a frame and forks in a basket, then had to source all other items. Built the crank, gearbox, laced the wheels, etc. That took me a while, but the bike has now done many thousands of miles in the past 15 years.

The ignition seems good. A local guy rebuilt the dizzy this summer for me. He backed off the timing retard screw so that it runs at full advance. I questioned him on that, but he said it runs best that way and then there is no issue with the timing accidentally being retarded. I've never heard the motor ping so far...

Nice! I restored a 1948 Red Hunter 500 single and a 1937 Square Four!