Flathead Cams

[Krylon32]

For a 4X3 5/16ths street motor. Isky 400Jr or Max 1? 32 highboy with a T5, 3.78 gears and 31 inch tires. Looking for a smooth running motor with a fairly smooth idle and good street manners. My last Flathead.

[Angledrive]

Isky 400Jr, My favorite cam

[KiWinUS]

KiWi-L100

[Ol' Ron]

Isky 1007B. Very ice street cam with good low end torque Stock valve springs with .060 shim, Excellent cam for stock or up to 276 cI and still turn 5K,
A cam insolation can cost up to 500 bucks these days, so gust work can be expensive. The max #1, 77B, 88 race cam and many others can't hold a candle to it, might as well run a EAB cam and save the money.
Gramps

[Tim Ayers]

There's a little more to it. What type of car, trans, rear end ratio, etc. Assuming you are talking a light hot rod I agree with Ol' Ron. The Max 1 would be last choice for your motor. I would also suggest talking to Kiwi Tony or Pete.

There are numerous stories of new Isky cams having serious issues with quality control. When these folks called Isky, they were told to pound salt. It would infuriating to say the least to spend big bucks on a new cam that isn't correct.

Tony or Pete can hook you up with a quality regrind for much less than a new Isky.

[GB SISSON]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by Ol' Ron

Isky 1007B. Very ice street cam with good low end torque Stock valve springs with .060 shim, Excellent cam for stock or up to 276 cI and still turn 5K,
A cam insolation can cost up to 500 bucks these days, so gust work can be expensive. The max #1, 77B, 88 race cam and many others can't hold a candle to it, might as well run a EAB cam and save the money.
Gramps

Just for a base line, is an EAB cam what would be original to a '49'-53 merc?

[STAN WHITE]

I am using a Potvin.425 Eliminator . I have one from the late 50s. I am running it in a 276 C.I. 59AB It is a 1/4X 5/16 Configuration. They were ground on a steel billet 1932 cam. Most guys think that it is to much cam for the street. I ran it it the drags and on the street. No problems. I have a couple of Ed Bingly Engines. He had Bings Speed shop in Santa Rosa. He was quite the Flathead guy back in the day. I also ran three Stromberg 48s with H&C Dual coil Distributor, No progressive linkage. Schafer Aluminum clutch $ Flywheel. Ed Did Exstensive Porting when doing the Flatheads he is the only one that I know of that cut the Blocks at the end ports and did his magic then welded them up.

[Ol' Ron]

The 52/53 Merc had an EAB cam with alittle more timig, ot sure about the lift, The EAB is ore available, and I have one in my 280. I like the way it pulls in the truck and there are very few hills in VT I can't climb even in OD. Excellent cam for a street engine.
Gramps

[Krylon32]

What;s wrong with the Isky 88? I used to get a Crower regrind from Baxter Ford Parts that was a clone of the 88. Ran good and no head work required, I probably used that cam in at least 1/2 a dozen engines with good results.

[Brian]

I too, am a fan of the 88

[JSeery]

I too am a fan of the 400jr, but I wouldn't consider it a "smooth idle" cam, LOL.

[JWL]

The 400 jr. is a bad choice for any long term(mileage) use. It is a high wear item. It provides good street power because it has relatively mild timing which means good lower RPM torque. However, it is "noisy" and the acceleration of lift is such that wear is a problem if sufficient spring rates are used to take full advantage of the full range of power.

[Bored&Stroked]

It kind of depends on the usage of the car, how much of a "cam sound" you want, etc.. I tend to run pretty stout cams - and I am happy to lose low-end power for higher RPM power (my choice). If it was my engine and the car was a lighter car with not too tall of rear-end gears, then I'd probably choose between the L-100, the Isky 1007B or a Potvin 3/8. All of these cams will run really well, will have a lopey idle and will make a 276 flathead a lot of fun.

Always make sure you check the timing on the cam, determine the intake centerline and install the cam to match the spec provided by the Mfgr. It you have a mill and a rotary table, it is no problem to re-drill the cam gear to set the intake centerline where you want it (or it needs to be!).

[Fred A]

Why is it that the majority of the replies leave out what may be very important in the choice of cams. My '40 came with a 59A and an old Isky full cam plus port/deck relief/heads. Rear gear was 4.44 behind a 18/26 geared ford box. Reason was clear why it was retired beneath a patio cover in 1971. A '40 is a middle weight car. Now all has changed as will be how the car is used. Too late for this time, I have found a new EAB cam in the Ford box with the plastic sheath unopened. Seems like a fair stock cam, snout modified replacement for my 99A engine for the same car. Now my gears have gone tall, 15/29/, 3.25. All these specs should be part of the answer. Not, 'I always run this or that'. You think Ford engineers just shot from the hip and didn't consider weight, street or highway use and gears? I know you're all racers and more is not enough. Must be getting old. Good Luck: Fred A

[Ol' Ron]

The cams you mentioned have an aesthetic value, and ther's nothing wrong with that. However if you compare the timing figures it the Tilden list you'll find them all very similar to a 3/4 cam. The L-100 doesn't work well in a small engine because the long intake closing kills a lot of low RPM compression by closing the intake balve very late. the 1007B has a faster lift rate. For the exception of the 400 JR.r most run very well on 50/lbs spring pressure. Now for the BIG reason. Any cam and lifter combination today will cost over $500, so you might as well get your money's worth.
Gramps

[Fred A]

Ron, in both your responses you laid it out in a real world, cam in your engine as the performance in "the truck" places the cam where some special performance issue is met. Many of us out west have done very well on the relative cheap with parts that may have been around since WWII or Korea from the surplus market. New cams are still floating around assuming that new is not that much better than good used. Just a clue as to where things perform well and how it is used in what kind of car and how it may be otherwise modified can complete the picture. Thanks Gramps: Fred A

[2935ford]

I had a MAX 1 in my 276 59a flatty.......ran great!

[glennpm]

Ditto on the, "runs great" with Max 1 in my 59A roadster.


Glenn

[tubman]

"Runs great" is fine, but what about an increase in performance over a stock cam? A stock cam also "runs great".

(BTW, I have a MAX-1 in the 258" engine I just built for my "T" tub.)

[Tim Ayers]

Like others have mentioned, we really need more information as what this is going in before a real recommendation can give narrowed down.

With your track record of past builds, we are all assuming it's some type of '32, but we don't know.

[Ol' Ron]

I like the Max #1 as well. however, thought of paying 500 bucks to install one now, gets a second thought. Might as well get something better for your money. Trouble is the definitions of "Better". Plan ahead!

[Krylon32]

For the guys wondering what it's going into refer to my original post.

[HotRodmicky]

Originally Posted by Ol' Ron

I like the Max #1 as well. however, thought of paying 500 bucks to install one now, gets a second thought. Might as well get something better for your money. Trouble is the definitions of "Better". Plan ahead!

I dont like the Max1, but
Yep
500bucks for Max1 is stupid.....
Much better cams on the market...

[HotRodmicky]

To answer the question.... 4.25x3 5/16 and a Eab or Merc cam....
But where is the fun?
With a 5-speed you can run a more fun cam.
isky 1007b... even if it is not that wild/fun
400jr is probably to much for your liking...
A Flathead is a torque engine not a RPM engine...
Isnt camshaft talk the most interesting talk about Flatheads?
:-)

[Admiral]

Talk to Pete at D&L Automachine. For a nice boost over a stock camshaft without being too hairy, he recommended the Isky 1007B, just like Ol' Ron did above. He ground one on an EAA core for me about a year ago and the workmanship is primo. I haven't run it yet, so I can't comment on how it actually performs, but I can't wait to try it out.

[flathead 39]

Sponsored Links (Register now to hide all advertisements)

My engine was built before I bought the car but I got a spec sheet with the car. I wonder if one of the cam gurus could rate the cam: 8ba bore 3-5/16 stroke 4-1/8 stainless valves, balanced lightened flywheel..cam Schneider, valve lift .375, duration 264, lash .012 -.012 adjustable lifters. Offy heads & dual Holly 94s, 10" clutch. Seems to have lots of pull throughout the rpm range

(I havent gone above abt 4k rpm.) I cant find a cam with these numbers on the Schneider site. Is this a good overall setup?

[Pete]

I just grabbed this from the HAMB.

"krylon32 said: ↑
What's wrong? I can't believe you HAMB guys don't have both the experience and an opinion on this."


Yes, everyone has an opinion. A few have experience. Although the info has been posted many times on here, I guess another time won't take up too much bandwidth.
A 400jr is a VERY poor choice for a street engine that is expected to live a long time.
It has very poor velocity and jerk numbers for longevity. It is a race grind.
Most of Isky mild grinds will live a long time. Some idle stock smooth, others have a slight lope which some people desire. The only way to experience what a certain cam is like is to find a car with one in it and see if you can drive it.
Even that is not too good because their engine may not be similar to what you plan. Most people choose too much cam for the type of driving they intend to do. You can make a stock cam have that drive-in rump rump idle just by tweeking the idle screws and it far cheaper.
There are certain cam grinds that you hear about all the time. Why is this you ask? It is because tomorrow no one remembers second place. Consistent winners are the ones you hear about most.
A cam can have fairly aggressive lift curve numbers but still be a good street grind if the numbers are applied right.
There are some that are right and quite a few that are way wrong.

[Frank Miller]

My take on the "nice lope at idle" is, here is a cam that performs poorly in the range you normally drive on the street. It needlessly wastes gas and promotes while sounding powerful but essentially doing nothing for you. :-)

Originally Posted by Pete

I just grabbed this from the HAMB.

"krylon32 said: ↑
What's wrong? I can't believe you HAMB guys don't have both the experience and an opinion on this."


Yes, everyone has an opinion. A few have experience. Although the info has been posted many times on here, I guess another time won't take up too much bandwidth.
A 400jr is a VERY poor choice for a street engine that is expected to live a long time.
It has very poor velocity and jerk numbers for longevity. It is a race grind.
Most of Isky mild grinds will live a long time. Some idle stock smooth, others have a slight lope which some people desire. The only way to experience what a certain cam is like is to find a car with one in it and see if you can drive it.
Even that is not too good because their engine may not be similar to what you plan. Most people choose too much cam for the type of driving they intend to do. You can make a stock cam have that drive-in rump rump idle just by tweeking the idle screws and it far cheaper.
There are certain cam grinds that you hear about all the time. Why is this you ask? It is because tomorrow no one remembers second place. Consistent winners are the ones you hear about most.
A cam can have fairly aggressive lift curve numbers but still be a good street grind if the numbers are applied right.
There are some that are right and quite a few that are way wrong.

[glennpm]

Hi,

I did some comparisons of four cams after learning how to deal with the graphics program, Gimp. Hard to understand without ramp rates to figure what could be best for a modified street application.

Glenn


PS Updated spreadsheet and added RPM chart

[Flathead]

I ran a 400jr in a 41 coupe 3/8 x 3/8 motor, slightly larger than OP's but close. I used stock springs and ran two 97's with direct linkage. Stock springs were easy on the cam and I did not need to wind it up like a race engine. Performance was strong no hesitation or flat spots, pulled real good low to high. I guess that puts me in the minority.

[Pete]

Originally Posted by Flathead

I ran a 400jr in a 41 coupe 3/8 x 3/8 motor, slightly larger than OP's but close. I used stock springs and ran two 97's with direct linkage. Stock springs were easy on the cam and I did not need to wind it up like a race engine. Performance was strong no hesitation or flat spots, pulled real good low to high. I guess that puts me in the minority.

Heavens no, it just puts you at the tail of the B main....lol

[Ol' Ron]

Interesting numbers here. The cam in my 280 is an EAB. I used it because everybody said it was a good street cam, and I've never ran one or new of anyone who did. The engine also has milled EAB head, so it is basically a stock Merc engine with 3 5/16+ .020" over pistons. now rhe truck is a 47 international with ford F150 trans and a Spicer 44 rear with 3.73 gears and posi. It's hard to explain the torque the engine has. It's perfect for Vermont as once in OD you never have to shift, unless you drop under 20 mph and it will climb a 14% grade inOD at 43 mph with the Tac turning 1300 rpm at WOT. Unfortunately it runs iur of wing around 3500 rpm. But I'm keeping it.
Gramps

[flathead 39]

Originally Posted by flathead 39

My engine was built before I bought the car but I got a spec sheet with the car. I wonder if one of the cam gurus could rate the cam: 8ba bore 3-5/16 stroke 4-1/8 stainless valves, balanced lightened flywheel..cam Schneider, valve lift .375, duration 264, lash .012 -.012 adjustable lifters. Offy heads & dual Holly 94s, 10" clutch. Seems to have lots of pull throughout the rpm range

(I havent gone above abt 4k rpm.) I cant find a cam with these numbers on the Schneider site. Is this a good overall setup?

In going back through the Schneider cams, mine comes close to the P-3/8.
Anybody had experience with this cam?

[Pete]

Originally Posted by flathead 39

In going back through the Schneider cams, mine comes close to the P-3/8.
Anybody had experience with this cam?

It is slightly less than a Potvin 3/8 so it should work fine on the street.

[glennpm]

Originally Posted by Ol' Ron

Interesting numbers here. The cam in my 280 is an EAB. I used it because everybody said it was a good street cam ....
Gramps

Yes they are Ron. The thing that is curious is comparing especially the Max 1, 1007-B and the EAC. The EAC has the largest open durations and the least lift. Max 1 the shortest durations and largest lift. BTW I have JWL's book and he lists horsepower for the Max 1 but no torque unfortunately. For the street its mostly about the great torque for Flatheads.

It would be great to have a full profile of the Max 1 and EAC to try to figure why and how each effects torque and horsepower better based on accurate ramps and nose information of the cams.

Biggles measured accurately the 1007-B here https://fordbarn.com/forum/showpost....7&postcount=16

[Automotive Stud]

I currently have a max 1, an 88, and a 400jr. I'd go with the 88 for what you are looking for.

[my2nd40]

Any opinions on a Potvin 3/4 super?

[glennpm]

Comparisons I did using a the convenient web page for camshaft below

https://mgispeedware.com/camshaft-calculator/

[Krylon32]

After reading all this I am left confused. I have ruled out the 400JR so now it's between the Max 1 and the 88. I have a good friend with a Max 1 in a 276 with fuel injection and his motor runs really good. I've used the Crower regrind that is similar to the 88 and it ran great. I think either one will do the job. I'm going to use Navarro heads and my biggest concern is selecting a cam that necessitates head work as I don't have a shop in the area to do that. I need a bolt on. Any more thoughts?

[Bored&Stroked]

If the Navarro heads have not been milled, I can't see you having an issue with either of your choices. You should have plenty of clearance over the valves. I'd still clay the pockets and the only area you really need to check is at the top of the 'eyebrow' cutouts - which is where the top of the valve gets the closest. The Drivers side is usually about .040 closer to the head than the Passengers side. Another good choice (which is what I'd use) is the 1007B grind. Pete can grind that profile for you . . .

[glennpm]

The Navarro seem to have larger chamber volumes than many other choices so you may not have an interference problem. Look at pages #4 and #12:



https://www.fordbarn.com/forum/showpost.php?p=23873&postcount=1


Looking for someone to comment on how close the four cams I compared are. The Mercury being the least aggressive.


Glenn

[Krylon32]

Since I've had good luck with the Crower regrind that mimics the Isky 88 I'm going down that path.

[Brian]

Good choice!

[Ol' Ron]

The only way to compare camshafts and other aftermarket Power adders is: to run them all under similar conditions. To pick a cam with similar numbers, use the one with the most area under the graph. Usually +/- 30degrees. The 1007B would win that comparison due to the quicker lift rate. Now thid is allot of BS fore most people and you choose the one you lie best, and that works for me.
Gramps

[glennpm]

Thanks Ron

[5851a]

Sponsored Links (Register now to hide all advertisements)

Originally Posted by Krylon32

For a 4X3 5/16ths street motor. Isky 400Jr or Max 1? 32 highboy with a T5, 3.78 gears and 31 inch tires. Looking for a smooth running motor with a fairly smooth idle and good street manners. My last Flathead.

JMO but smooth idle tall tires with od on 3.78 I would chose the late Mercury cam.