427 stroker install on Pontiac G8

StrykerGTss

Forum Member
So the car is parked for winter, I'm mid build on it and tossing a few options around. Initially I'd taken the engine apart to do a cam swap and install ported heads. After it was apart, I decided to expand the project a bit..

Current upgrades are:

OTR Cold Air Intake
Ported TB and Intake Manifold
Ported LS3 heads
Doug Thorley 1 3/4" LT headers (non-cated)
Borla catback
Underdrive crank pulley

I was able to come up with an LS3 block, the current plan is to pick up a 427ci stroker kit. Up for recommendations on the internals, but here's what I'm thinking:

Callies Compstar Crank 4.10"
Manley H-Lite Series Rods 6.125"
Wiseco 4.07" Pistons dished, dish size is up in the air right now

Here's where my dilemma comes in. The cam I purchased was bought with the intention of adding a blower down the road (specs are close to 224 duration .581 lift, don't have them in front of me), so I know I'm leaving some HP on the table. Also, considering lowering the compression to 9.5 or 10:1 in anticipation of the SC.

My buddy is trying to convince me to sell the cam I purchased, and go more aggressive now (LG Motorsports G6X3, specs are around 240 duration .630 lift I believe). Then if/when I decide to add a blower, pick up a FI cam at that point. He's also pushing to keep the compression at 11:1 or higher to pick up some additional power.

I know that the fuel system and a stall converter will need to be upgraded as well. Also have upgraded valve springs and pushrods from comp cams.

Has anyone done a build like either of these? The goal is 550hp/550lb-ft at the wheels, I'm thinking either of these setups should get me at least that much. Really trying to avoid any drivability/idle issues. Also need to keep the car calibrated for premium fuel.

Thoughts and opinions are appreciated.
 
1.you probably wont miss the 11ci at all with a supercharger or even n/a for that matter.
2. with that much stroke the piston can protrude below the liner leaving the piston unsupported. boost puts even more stress on the piston. the lack of support also can cause the piston to rock in the bore causing wear and the rock also unseats the rings causing oil consumption on street engine

550 n/a with a stalled auto will be difficult. no problem at all with the supercharger
 
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