well my plan was to do a boosted 6.2 in my 04 shorty but due to a head bolt hole stripping on my ls6 engine in my zo6 decided to put that in my car

so.....

that leaves me with ported 243's, ported fast 92, 36lb injectors, BTR stg 2 cam 227/234 614/576 113+2 from my ls6

i know its not a optimal setup for the 4.8 but what kind of power would it make? all that with kooks long tubes, cai & tune

 

Why not have the LS6 block repaired? if it's stripped they can but a thread insert in it.

 

ive thought of that, i have to pull the engine to get it repaired and i would not do just one since i have nitrous on the car (if one gave up probably others will heads been off a few times) plus once the engines out id forged it so im looking at about the same cost to just have the 6.2 forged and install it in my car

something in the back of my mind keeps telling me put an iron block in the truck and turbo it so i might just boost this 4.8 or get a 6.0 iron block down the road but since ill have the parts from the ls6 wont cost me much to swap them in the 4.8 for time being and see what it does

 

243's are gonna lower compression though...

 

have an idea on how much?

 

There is about a 4cc difference in the chamber. You can mill them down. but they get thin and if you gonna spray or turbo that's bad news.

 

this is why i asked! thank for the info

figured if i can install those parts and crack 350 or so out back it be ok for my daily pickup till i get it boosted

 

In factory trim it would be around 9.0:1 compression.

 

my 4.8 with a 212/218, stock 862s, TBSS manifold, 92mm throttle body, longtubes, 4l80e made 304/300 on motor. I don't think the 4.8 has enough to push the 243s and that's a pretty big cam but anythings possible lol.

 

Gm rates the gen iv 4.8s at 8.8:1 compression and they are just 799/243 heads and flat tops. Real scorchers.