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Vinny P 01-22-2006 05:05 PM

Re: 454 MPI MAG upgrades
 
10:1 is pushing it. Especially with a steel head. You will have to consider what exhaust to run. To get 550, you may need a big solid roller. Reversion and idle quality will be a problem. You may have to go for dry pipes, I had to.

800XCR 01-22-2006 06:43 PM

Re: 454 MPI MAG upgrades
 
I'm willing to learn, educate me.

ECeptor 01-22-2006 06:53 PM

Re: 454 MPI MAG upgrades
 
Seems like a reasonable goal to me. Might have to stretch for the last 50hp, but 500hp should be easily obtainable with good aluminum heads, true header exhaust (think CMI sport tubes), the right cam and the right intake (I'm a carb guy so I don't know what you'll need to do to your FI).

Just get matched components designed to let that baby rev up to 6000rpm and you'll get there (only 481 ft-lbs of torque needed at that rpm!).

JasonSmith 01-22-2006 07:30 PM

Re: 454 MPI MAG upgrades
 
I've also been told th swap out the rocker arms for 1.8's. Any truth to that? On a stock setup that is.

Vinny P 01-22-2006 08:35 PM

Re: 454 MPI MAG upgrades
 

Originally Posted by JasonSmith
I've also been told th swap out the rocker arms for 1.8's. Any truth to that? On a stock setup that is.


If you are changing the cam, just get the right lobes ground. No need for 1.8 rockers then.

JasonSmith 01-22-2006 09:46 PM

Re: 454 MPI MAG upgrades
 
Just thinking in the in-term....

Pat McPherson 01-23-2006 07:23 PM

Re: 454 MPI MAG upgrades
 

Originally Posted by JasonSmith
I've also been told th swap out the rocker arms for 1.8's. Any truth to that? On a stock setup that is.

I just bought a set of 1.8 roller rockers to replace the 1.7 stamped steel on my 502MPI.
I was going to do it last year during my rebuild but I ran out of $$.
A few people have told me that the valve guides will wear out faster with 1.8 but with such a mild cam in the stock engine, I'm going to chance it.
Desk-top-dyno shows that the added lift should be good for +15-20HP. And with +5-10HP from going roller, I'm hoping to see another 150-200rpm on top...
We'll see in the spring... :drink:

pkspx 07-10-2006 12:51 PM

Re: 454 MPI MAG upgrades
 
N/A Setup from Gellner Engineering

9.6:1 JE forged pistons
Blue printed and balanced
stock GM crank
stock rods
Dart Alumn ported and polished heads
Roller Rocker lifers
crancams camshaft
MSD ignition
holley carb
dart hi riser intake manifold

dyno 514hp 510tq.

SB 07-10-2006 01:07 PM

Re: 454 MPI MAG upgrades
 

Originally Posted by JasonSmith
Ok, want 550 Hp and factory looks out of my 454 Mag Mpi's. They are the 385 hp models. No superchargers (I think)
Who has the proven combination?

Build a 540 and keep the 454 FI intake plus all assorted decals. Don't forget to paint everything black as it was. :D

BY U BOY 07-10-2006 01:49 PM

Re: 454 MPI MAG upgrades
 
Stoke It To A 496.


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