454 MPI MAG upgrades
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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.
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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!).
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!).
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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.
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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 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...
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Patrick
Patrick
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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.
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.
#19
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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?
Who has the proven combination?
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