Flathead Cam recommendation

C

cobbie

Member
I am Building a AV8 Open Cab pickup. I have the Engine all machined and ready to put it together. It is an 8ba that was bored 3 5/16"with Ross Pistons and 4" Merc Crank, and It has been balanced. I have Navarro Heads and Intake Manifold and plan on running 3-97 Carbs. My problem is I have purchased a Max-1 reground Cam but now I am thinking that might not be not enough cam, I am thinking I need something a little more aggressive. I thought I might ask some of you Flathead Guru's, this is just a weekend play thing I think I am looking for something that has a lopie idle and good power, It would be OK if was a little harder to drive slow. Thank all of You Barners in advance and Happy new year.
 
Other considerations are vehicle weight (your pickup should fairly light), rear end gear ratio (a hot cam likes a lower gear ratio) and driving style.
 
I have an L100 in a 276 8ba in a '38 Club Coupe. Stock drive line wiht 3.78 rear. 300 miles on it, just changed out the break-in oil today.
I have 8cm heads clearanced for about .050", one carburetor, Chev. distributor. It does have a good rumpity idle and, not having anything to compare it to, seems to have good power. Runs great on the open road. The negative is low speed drivability, it rocks/surges on deceleration below about 30 mph and surges with the rough idle when easing around in low gear. It pulls away strong from below 5 mph in second when given a little throttle. These are my observations about the cam. If anyone has different experiences I hope they will give their opinions.
 
I have the L-100 in my 276 8BA that's in my '36 at around 2900lb. with a 3:54 and a 4 speed top loader idle is somewhat lumpy but is smooth through entire RPM range and no problems on deceleration.
 
My engine is slightly larger in size @ 3.345 bore & 4.125 stroke.
Aluminum heads, 2 big carbs, larger valves.
I run a Potvin 425 ground by Pete here on the forum.
This cam is much more tractable than I had been told,
and runs really well throughout the rpm range.
Idle speed is a bit high at about 900 rpm. Highly
recommend this cam & Pete
 
36tudordeluxe said:
I have the L-100 in my 276 8BA that's in my '36 at around 2900lb. with a 3:54 and a 4 speed top loader idle is somewhat lumpy but is smooth through entire RPM range and no problems on deceleration.
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Maybe I have some more tuning to do.
 
Interesting in that I am pulling an Isky 77(old fashioned full) cam from the 59A for my '40 coupe. Looking and found early fifties stock cams that I expect to be more to my taste in engine performance. Long gearing and heavy car make low end performance much more important than with a light car. The EAB Ford cam is strongly considered even though I also a big fan of the crab dist. Different Strokes: Fred A
 
I think the L-100 needs some compression to operate at low RPM's using the Merc heads wouldn't give it much, I'd go to the EAB heads and do the same piston to head clearencing. The Isky 77B is so mild I think it's a wast of money. The Potvin is a very good cam, but need some heavy springss. However the Isky 1007B and the L-100 run well with the stock springs and a .060 shim. Just remenber ALL these cams take away low end torque. Best thing to do is buy all of them and find the one you like, as I did.
 
Anyone had any experience with the Giovanni cams? have a 8ba to put in my 32 5w roundy round for now, & a 59 'L' code which I hope at some point to rebuild & replace it. The word was our family friend ran the 32 using a Giovanni cam for at least a portion of his racing years, I do recall the car having something rather radical as it would buck & lurch as he exited the pit road on to the track which ran parallel to the front straight & directly in front of the bleachers. Sorry for horning in on the thread, Ron B.
 
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Yes on the Giovanni cam, ran his 999, which I laterfound out was a copy of an Isky. No never ran the 1007LD or the 1007. Can't figger out where Isky got his numbering system.
 
Thanks ol Ron, I'll need to ck. my stash as I do have several track cams well oiled however questionable use as most came from local racers & poorly stored.
 
The engine in my truck is a 280 ci engine with everything stock except the pistons, I do have a 2GC carb on a bored intake and SBC dist. The engine is a joy to drive. Rear is 3.73 and has a 36 % OD. EAB heads were milled to provide .040 piston clearance. CR is aprox 8:1 Engine was formally a 276 street engine with L-100 cam, heads , etc. Engine was stored for several years with no spark plugs and I bored it to 3 5/16 + .020" using Egge pistons with Metric rings from a Volvo. Low end torque is hard to believe.
 
Ol' Ron said:
The engine in my truck is a 280 ci engine with everything stock except the pistons, I do have a 2GC carb on a bored intake and SBC dist. The engine is a joy to drive. Rear is 3.73 and has a 36 % OD. EAB heads were milled to provide .040 piston clearance. CR is aprox 8:1 Engine was formally a 276 street engine with L-100 cam, heads , etc. Engine was stored for several years with no spark plugs and I bored it to 3 5/16 + .020" using Egge pistons with Metric rings from a Volvo. Low end torque is hard to believe.
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and you are running what cam in the 280 ci engine?
 
My pickup is very light just a little over 2200# but that will change a little with a flathead instead of a 4 banger, I am using a winters quick change at 3.48 but the ratio can easily be changed if needed. The L-100 sounds good but I haven't found any for sale. How does the 400jr compare ? there seem to be a lot of them available. Thanks every one for the help.

Cobbie
 
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