1997 7.4 300hp?
#12
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THE LATE MODEL 454S THAT IVE SEEN HAVE HAVE BEEN 7/16 ROD BOLTS W/CAST CRANKS BUT THEY HAVE BEEN 4 BOLT WE HAVE BUILT THESE ENGINES WITH STEEL CRANKS AND 9.00:1 PISTONS HYDRAULIC ROLLER CAMS AND MADE 460 HP EVEN WITH THE SMALL HEADS I HAVE THESE ENGINES IN SEVERAL DIFFERENT BOATS IN SOUTH FL. AND THEY REALLY WORK GREAT. ONE CUSTOMER THAT COMES TO MIND HAS A MAGNUM WITH TWO OF THEM WITH OVER 400 HOURS AND IS TICKLED WITH THE PERFORMANCE. BUT YOU NEED THESE PISTONS AND A CAM WITH 225/235 @.050 OR CLOSE TO THAT TO GET GOOD POWER LIKE YOU WANT.
SINCERELY
LAZ MESA
WWW.MESABALANCING.COM
SINCERELY
LAZ MESA
WWW.MESABALANCING.COM
#14
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Join Date: Jul 2001
Location: Rockford, IL
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I am in the process of building up my 1999 310Hp/7.4MPI.
My plan:
-L-29 Vortec Heads have been bowl ported, New stainless severe duty valves installed with new double valve springs.
-New cam with spec. 229°/229° .541/.541 114°LSA
Note this cam is custom ground to max out the stock GM lifters, push-rods, and non-adjust rockers.
-Stainless marine exhaust
-Reprogrammed ECU for the MPI.
I have been told that the MPI will hold my combo down to about 375HP @ 4600rpm and if I change to a carb it would make about 410HP @ 5000rpm.
We'll see how it goes.
I also corresponded with MadMax on this subject. He had a 1997 300HP 7.4. He changed out the peanut port heads for a set of Vortecs. Big improvement for not a lot of $$.
My plan:
-L-29 Vortec Heads have been bowl ported, New stainless severe duty valves installed with new double valve springs.
-New cam with spec. 229°/229° .541/.541 114°LSA
Note this cam is custom ground to max out the stock GM lifters, push-rods, and non-adjust rockers.
-Stainless marine exhaust
-Reprogrammed ECU for the MPI.
I have been told that the MPI will hold my combo down to about 375HP @ 4600rpm and if I change to a carb it would make about 410HP @ 5000rpm.
We'll see how it goes.
I also corresponded with MadMax on this subject. He had a 1997 300HP 7.4. He changed out the peanut port heads for a set of Vortecs. Big improvement for not a lot of $$.
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Patrick
Patrick
Last edited by Pat McPherson; 03-17-2004 at 08:50 PM.
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I'm interested in those heads. Please e-mail me @[email protected]. I will be using them on a Gen V 454
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