Hi, I'm Wes! I am 21 and always trying to learn as much as possible about LS engines and boosted applications. I proudly own a 02 WS6 Trans Am right now with a built 6.0 LQ9 Engine running the P1-SC-1 Procharger on 6psi already has the front mount intercooler, aftermarket driveshaft for 1000+HP, Moser 9in with aluminum center section, and Viper Stage 3 T56 Transmission good for 1100+ and a ton of other modifications. I'm wanting to start a project build on a 408 stroker engine for boosted applications as well to put in the car. Here is a list of the items of things I'm wanting to do. If you see any improvement at all please let me know!

LQ9 LQ4 6.0 Iron Block Bored 4.030"
Lunati Voodoo Forged 408 Stroker kit for Turbo LS2 Engines
(Have to figure out tooth number being 24 or 58)
4.00" Stroke 6.125 H beam rods Cleavite Racing Main and Rod Bearings
Mahle Forged Powerpak Dish Pistons -28cc
Melling High Volume CNC Oil Pump
AFR 317 CNC 230cc 72cc Aluminum Heads
LSX 102mm Intake
LSX 102mm Throttle Body with TPS
Fast Billet Aluminum Fuel Rails
F1 Procharger
Comp True Double Roller Timing Chain
Everything will be bolted down with ARP


Still trying to find a cam to run with this. I don't want a thumping cam like what I have now. Rather be smooth and quiet low duration, but still suitable for good RPM range and power. As for the heads would 230cc be ok or should I go with 245cc for more air flow? Any suggestions on Head Gaskets, rocker arms, and springs duel or beehive? With this combination my compression should be around 8.6.1 before boosting. What would you suggest is a safe boosting area and still be on pump gas without meth? I believe its safe to go 11.5.1 compression on 93 octane. Not sure how much boost would be required to bring the compression up that high however. I have no idea what kinda RWHP to expect from this lil recipe I created, but Im hoping a good amount. Any tips or pointers on everything I've listed would be very much appreciated!! This is going to be a winter project so I'm in no rush =)

Thanks, Wes!

 

I would do different pistons, Diamond or Wiseco personally. Shoot for about a 9.0-9.5:1 Compression Ratio as well, 11.5:1 is too high for Pump. Also, boost does not "add" compression. Have Martin @ Tick specify you a Camshaft. The AFR 230cc heads will be fine. I would do LS9 head gaskets. Factory rockers with a trunion upgrade will be fine. Dual springs for sure.

 

Ok thanks Ill keep that in consideration on the pistons I don't know much about Mahle or Diamond, but I've heard good from both. I was going with the LS9 head gaskets just wanted to see if someone would mention them to make sure it was the right choice. The part Im confused on is boost doesn't add compression? Kinda lost on that part if you will explain. Air being forced onto the piston from a procharger or turbo would make for more compression when the piston has topped out and everything is packed together before the combustion. I would assume that brings the compression ratio up.

Thanks, Wes.

 

Your static compression ratio has absolutely nothing to do with how air is delivered to the motor. Your static compression ratio is a function of bore, stroke, deck height, head gasket thickness, piston volume, and head volume.

Its kinda telling you how much "open space" there is between your piston at top dead center and the head. More space=lower compression, less space=higher compression.

The cam will play a role in your dynamic compression ratio

 

I understand that static compression is the bore, stroke, heads, piston volume, etc. I have all that listed in my parts 4.030" bore 4.00" stroke, 317 heads 230cc 72cc CNC, Dish Pistons -28cc all that being said the compression would be 8.6.1 before boosting. I know more space less compression less space high compression. A boosted engine has to have low compression due to the procharger or turbo forcing the air onto the piston bringing the compression up. Maybe Im missing something Im not sure figured that was basic logics of an engine. Im just trying to figure out how much boost I can run on 93 octane without spark knocking or causing damage to the engine. I also know it depends on the tune of the vehicle as well. Just getting a rough estimate with the F1 Procharger and this application. I was figuring around 15-18psi would be Ok and still make decent power.

Thanks, Wes.

 

Boost doesn't necessarily mean low compression, it just gives you a larger tuning window. Again, boost does not add compression. It adds cfm into the air/fuel mixture. Also boost is not what you should be worried about, figure out what HP you want, whether it be flywheel, or wheel. Then determine what cfm will get you there.

 

Is 800-1000RWHP possible on pump gas with that combination?

 

Which Procharger? A, C, R, X?

 

Im no boost guru but im pretty sure cfm of airflow does not necessitate higher octane, just fuel. On the other hand boost does because it increases compression. EFFECTIVE compression is what youre trying to figure out and the effective ratio can be calculatef through online sources. Just make sure when you calculate that all motor compression is used with 15psi and new bottom end numbers are used with 15psi plus how much boost youll see on the boost guage. This is due to atmospheric pressure being 14.7psi. Easier and safer to round to 15. Good luck.

 

Thanks blue, and Im using the F1A Procharger