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My current cam is an isky mega 292 hydrolic cam.Its a 454 engine and the cam is a 590/590 lift and 292/273 dur. Im running a 2800 stall and 373 gears. Should I switch cams to this one below or is it fine where its at? Ive just been told that my current cam is too much for the street, as that is all I primarly drive it is the street.
http://store.summitracing.com/partde...5&autoview=sku
Thanx
david
A whump, A whump man I can hear that now. With your 2800 stall converter you might keep it going, but yep way to much for just a street engine.
It all depends on your static compression ratio and the intake closing point of the cam. If your c.r. is high, you might run into detonation problems with the shorter cam. Do you know what your c.r. is exactly, no guessing??
It was suppose to be 10:1 but my engine builder said that with the head gasket he used its around 10.5:1 I have not had any problem with detonation and I alawys use pump gas. I have edelbrock rpm performer heads.
Very unlikely that just a head gasket change will make 1/2 point increase in c/r....back to basics, you have to know what your c/r is, for sure, before you go picking cams. That's one of the first things they will ask you. I would think, for average street driving, you should stay in the vicinity of 230 to maybe 244 dur. at.050, but a lot of that choice will be dictated by your c/r. You might have to bleed off some compression. Check with your builder to find out for sure, no guessing allowed!;)
Lets see... Isky says 244 duration@ .050, .590 lift with a 108 LSA. If you do actually have 10-10.5 compression ratio I would stick with the cam you have. The smaller cam might just be enough to detonate on pump premium. You are probably on the edge right now. Plus, I assume this isn't a daily driver right? It's a 454, they have plenty of torque to begin with, so that Isky cam is gonna be plenty streetable. Thats the beauty of Big Blocks is all the torque! What kind of heads do you have on it? Stock Iron or aluminum? That makes a difference too.
Nevermind, I just read they are Edelbrock RPM heads. So... if you do have 10.5-1 comp. it would probably not detonate but you may have to back off timing. But like techinspector said the best way to do it is to be positive. Find the formula for compression ratio online. You need to know the piston dome volume, chamber volume, head gasket thickness, etc. You can get all that info from your engine builder.
I know this is still kinda guessing, But when I had the engine built ir was made to be 10:1 compression. It was built once and spun a bearing so we had to rebuild it again. Then he said he got a differant gasket this time on the head gasket so it would raise the compression a little.
thanx guys for the replys, Ill have to go try and get a hold of this guy. Hopefully he remembers if i get ahold of him.