Hi you all, I am goin to rebuilt my 1956 olds 324 engine next month and have some more performance out of it, Does any one have a suggestion which cam I should use? I have 6 Holley 94 on top(2 working ones at the moment, but want to have them working all 6) The engine is pretty standard now, I think. Also what pistons? thnx Anton
Don't know but I do know the Isky cam in the Deuce Roadster Jimmy White (hemi coupe on here) built for Ed Havins sounds wonderful.Heard it in Choppertown and did rewind that part of the movie several times...also has 10:1 Egge pistons.What a great sounding Olds mill that is !
You should contact Lunati and ask to talk to a guy they employ called Harold. He used to own his own cam grinding business down south someplace (Texas i think). He had to close shop due to economic reasons not becuase his cams weren't good. He has a great reputation over at Realoldspower.com and is highly respected. I wish I knew his last name but don't. His company was called Ultradyne and we called him UDHarold which was his on line moniker. You might be able to contact him there even. I got one of his cams in my 455 and like it very much. Dan
I remember Ultradyne, alot of the circle track racers loved those cams, glad that he is still in the business. I had an Isky E2 in my 394 Olds back in the early '60's, although it was a mild cam by Isky standards it was one mean sounding engine. Good luck with yours, can't beat those original Rocket V-8's!
This is gonna sound goofy as hell... It's all about whatcha want inna cam. If you wanna sound fast - well, it ain't gonna be fast on the street. Big overlaps make big power up high, but they ain't got nuthin' on the bottom end. That log manifold yer runnin' is a clue - if you plan on takin' it full house, then you'd normally pick a long duration/high lift cam. This pick will go like stink down the quarter-mile, but won't run worth spit on the street. You'll load up plugs faster than pete can slide the cheese off his cracker. We need a little more info to help you pick. Same goes for the pistons. You want something that's quiet in the bores - or do ya wanna make big power?
Thanks all for info. I use 3 speed Lasalle trans. I need a cam for street use, not too wild, same for pistons. gr, anton
I don't know if Isky still makes them but either the J-202 or J-303 flat tappet cams work great in Oldsmobiles.The 303 is a little lumpier but really works on the top end.Don't remember the specs(I had mine 30 years ago)but I'm sure you can find them.
Okay - If you're building for the street - a mild cam is the way to go! Having said that, it's always nice to have some overlap so's the motor still cams a bit at the lite; let's folks know that you've got some go to go with the show. this type of cam was known as a 3/4 race cam back in the day; dunno what the current rating of duration is, but the 'old' method (measuring the ramps for total duration) would be a 270-ish degree duration and a .400 (or so) total lift. I think this translates into a modern cam duration in the 250's, not accounting for the ramp for hydro tappets. This will give you the 'sound' of a cam and some decent midrange torque to go with a nice top end. When it comes to cams - less is almost always better! The problem you'll encounter is the cam has to be matched (somewhat) to the intake. With a rumpy cam, you'll be hard pressed to make enough vacuum to properly meter a 6 X 2 setup. that's not to say it can't be done (assuming you go progressive on the outboard carbs) - it's just a lot of work. As for pistons - On the street, a set of stocker cast pistons are fine. They'll run quieter than a set of racin' pistons...Heck, what's in there may be just fine! If it was a really high-comp high rev mill, then forged slugs are the way to go. Forged pistons hold up to preignition better than cast, and are stronger for blown engines or compression ratios beyond 10:1.
Thanks chuckspeed! yes, I read a lot in the old mags about this 3/4 cam installed in olds engines. Is it better to stay with the 2 middle carbs and blank the other 4 94s? greetz Anton QUOTE=chuckspeed]Okay - If you're building for the street - a mild cam is the way to go! Having said that, it's always nice to have some overlap so's the motor still cams a bit at the lite; let's folks know that you've got some go to go with the show. this type of cam was known as a 3/4 race cam back in the day; dunno what the current rating of duration is, but the 'old' method (measuring the ramps for total duration) would be a 270-ish degree duration and a .400 (or so) total lift. I think this translates into a modern cam duration in the 250's, not accounting for the ramp for hydro tappets. This will give you the 'sound' of a cam and some decent midrange torque to go with a nice top end. When it comes to cams - less is almost always better! The problem you'll encounter is the cam has to be matched (somewhat) to the intake. With a rumpy cam, you'll be hard pressed to make enough vacuum to properly meter a 6 X 2 setup. that's not to say it can't be done (assuming you go progressive on the outboard carbs) - it's just a lot of work. As for pistons - On the street, a set of stocker cast pistons are fine. They'll run quieter than a set of racin' pistons...Heck, what's in there may be just fine! If it was a really high-comp high rev mill, then forged slugs are the way to go. Forged pistons hold up to preignition better than cast, and are stronger for blown engines or compression ratios beyond 10:1.[/QUOTE]
Not sure if anyone mentioned this yet or not... There are three cam blanks for early Olds rocket engines. I'm not talking about the grinds, I'm talking about the physical blanks: '49-53 303 and '54-55 324 (small journals) '56 324 and '57-8 371 (large journals) '59-60 371/394 and '61-4 394 (large journals, but also 1/4" longer of a cam) Make sure you get the right cam blank and cam bearings for your year block.
Thanks to this old thread and FINALLY a journal size chart listed... I now know I have a cam to fit my 1955 324. But, is my lift too excessive for the stock piston clearances? My hyd cam is 275 duration measured at .004 lift at the lifter, and would have .570 lift at valve with the 1.8 324 rockers. I could use the 1949-51 1.5 rockers to get it down to .477 lift at valve. Intake is a 2x2....will this cam work on a stick trans, early rod with 3.50 gear? Any ideas? Thanks
Most cam grinders cut down the base-circle to get the desired lift and duration. This will necessitate the use of either adjustable pushrods (a pain) or adjustable rockers (hen's teeth are easier to find). I'm runnin' a TRW 3/4-Full Race (that is what it was listed as in 1964 [no specs, sorry], obsolete today) hydraulic pushing Crane anti-pumpups in a large journal '56 324cid. Gotha adjustable rockers were available back then, after a 40 year hibernation, are jiggling the valves again (past 4 summers!) It'll idle at 650rpm with a nice (not bad-to-the-bone) rumpety, rumpety at the pipes. Any suggestions on rocker arm substitutions? These engines run an almost straight up valve angle, not at all like the sbc 23* or the LA Dodge 18*. Much appreciated.
F&J You are getting close to max lift at .580--.585 ,,ought to be ok at .570 with flat top pistons. Sure way is to clay the top of piston ,,roll her over with valves set a little tight for good measure. Cut impression in clay at closest point to the piston, any over .070 thickness you are safe.
Give Ross a call (Ross Racing Engines 330 544 4466) He sent me a Isky 3/4 and I'm very happy with it. I lost a little torque on the bottom but gained big power from mid and up. Has a nice bit of lump in the idle but still has plenty of vacuum at idle, perfectly streetable. Just tell him what you want and the weight and gearing in your car and he'll grind one thats just right.
I wonder if this might be why Olds enlarged cam journals in 1956. In 1956 Olds produced the#10 better breathing heads. They then needed more valve lift to go along with the improved heads. Higher cam lobes were not possible since the journals were too small. Larger journals allowed higher lobes. Does that make sense? Greg
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