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mill9876 07-19-2011 07:13 PM

454 build questions on cam and carb
 
Im in need of some one to tell me a good size of the cam and carb needed for my build up of the 454 so here is what I have so far

SCAT
crankshaft 4.25
forged I beams 6.135
flat top forged pistons .030 over
9.0-1 compression
cast iron 336781 heads with 2.25I 1.88E
edelbrock rpm air gap
looking for cam size
looking for carb size

this is a gen 6 roller cam block and has stock manifolds and quick silver through hall exhaust
I am now looking in to EMI thunder exhaust after reading the posts can any one tell me if this exhaust will flow good for this set up
any help would be very appreciated thanks guys

picklenjim 07-19-2011 07:40 PM

If it's a mark 4 this cam.
http://www.summitracing.com/parts/CRN-139011/

This carb.
http://www.jegs.com/i/Holley/510/0-9...oductId=743728

1BIGJIM 07-19-2011 08:33 PM

One of the biggest factors for a cam is
WHAT exhaust do you have or plan on having?

mill9876 07-19-2011 09:38 PM

sorry its a gen6 with a roller cam and im runing stock manifolds with quick silver through hall exhaust on a 1997 baja 202 islander

Griff 07-19-2011 10:08 PM

With stock Merc exhaust, you are severly limiting the cam choice and ability to make more power. You can really only use slightly more than a stock magnum cam or you will get water reversion.

picklenjim 07-19-2011 11:53 PM

This is the cam for the Gen 6.
http://www.summitracing.com/parts/CRN-168731/
As mentioned exhaust will be a big factor.

DareDevil 07-20-2011 03:38 AM

call BOB Medara !!!!!

pantera232 07-20-2011 05:36 AM

I have similar set up with approx .6 lift cam setup...

What horsepower do you think he will see with this setup?

I run a 750 dp holly carb, if i dont ease into the top end it stutters occasionally but thats prop a fuel pump concern..

I had to add 10" pipes welded onto my risers with a stainless marine exhaust bc of reversion.

mill9876 07-20-2011 07:49 PM

looking in to EMI exhaust

jeffswav 07-20-2011 09:10 PM


Originally Posted by mill9876 (Post 3457035)
Im in need of some one to tell me a good size of the cam and carb needed for my build up of the 454 so here is what I have so far

SCAT
crankshaft 4.25
forged I beams 6.135
flat top forged pistons .030 over
9.0-1 compression
cast iron 336781 heads with 2.25I 1.88E
edelbrock rpm air gap
looking for cam size
looking for carb size

this is a gen 6 roller cam block and has stock manifolds and quick silver through hall exhaust

any help would be very appreciated thanks guys

Get the exhaust with long risers.
Your compresion will be lower than 9 to 1, more like 8.7 to 1. I have 8.9 to 1 and I have 489 with flat tops and 110cc chambers. A crane 731 would be good, or get a custom roller from RMbuilder. You may want to use 2.19 valves, you will want to do a good job on bowl blending with bigger valves. Here are the head specs 336781.....73-85...oval...OPEN...454, 118cc chamber, 256/114cc ports


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