Camaro-BMF

Hey guys I have the 383 Block and a pretty good pair of heads, basicly the whole setup, I want a really big cam for that engine witch is the best???


- Will the 292 XFI cam be great (242 / 248, .584 / .579 113 LSA) or

- CC503 Cam (224 / 230, .502 / .510 112 LSA)

za355tx

iTrader: (108)

Those two cams are not really even comparible. If you are set on an off the shelf cam the GM847 is a nasty cam. But for like $40 more you can have Lloyd Elliott spec a cam for your specific application.

JAKEJR

Why do you want a "really big cam"? What are your plans for the car? Bigger is not always better.

The 292 is 3 sizes bigger than the 503 and will perform dramatically differently in your 383. My view is the 292 has just too much duration for a 383 engine that isn't specifically built for its high RPM power range. It will probably be much harder to tune for too.

I suspect idle will be awful and vacuum will be so low that you may need a vacuum cannister for the power brakes to work reliably.

Not only that, but on another Forum, a guy has an on-going thread about how little power the 292 made in his engine; something in the low 320s HP on the dyno. Virtually all the responses to his post say he's just running too much cam.

230/236 @ .050 is the biggest I'd recommend if the car is going to see any street duty. More than that will cause the engine to lose too much low end torque.

Are emissions an issue?

Jake

West Point ROCKS!

96capricemgr

iTrader: (1)

292 will make plenty of vacuum. I still wouldn't use it but just saying there are a lot of guys offering advise who wont know anything but how to run a computer simulation.

Camaro-BMF

hmmmm.ok will the 292 is out of the question, i guess ill stick with the cc503

Puck

iTrader: (17)

Seriously?

Those cams aren't even in the same league. The right cam depends on your heads and the rest of your combo so nobody can make a suggestion without that information. I would let AI or LE spec you a cam inbetween the two...both cams have their places but the 503 is a bit small for a properly headed 383 and the 292 is too big for most.

slp223

iTrader: (1)

I have a comp 306 cam in my 383 that I have been happy with just to throw another option out there.

SpeedDensityZ

iTrader: (5)

The 292 was too big for my 383. Get a custom ground cam taylored to your setup.

96capricemgr

iTrader: (1)

Honestly I would probably be looking at low 230s intake. As said somewhere right between the two you chose.

Camaro-BMF

ok cool, man building this car has been pain, lol Im hoping it will be all worth it

WS Sick

The 503 was the first cam I had in my 383 and it was a dog, very finicky to tune (mid throttle pinging) and the car was very dissapointing with it.

I switched to a GM 847 and after tuning it made so much more power it was rediculous. OVER A SECOND IN THE 1/4 MILE !!!!!

It is smelly at idle, but the torque with a 383 is allways there.
No problem with brakes and such either (vacuume).

I am now running a custom HR in my new motor (240/242 .050, .600/600 lift 111 lobe sep ,107 ILCL)

But my new motor has 11:1 compression and my old motor had 9.8-10.0.

Havent gotten any track times yet but hope to have alot by the end of the year.

My old set-up used the same 190 AFRs I am still using , but I went up to a 2.05 int valve and a better valve job than what AFR provided (which gave the heads almost 20 CFM in places)
The cam builder used an almost identical lobe on the int and exhaust because of the exh flow of the heads. So you can take that custom grind with a grian of salt since it was speced for my heads.