okay this will be an earful so here we go.

I picked up a 4.8L with 100k miles she runs fantastic. Im getting ready to dump it into my G body and want to go forced induction. Turbo seems the be the answer but I don't have the best fabrication skills so id like to stick to a supercharger-

I see the LSA caddy superchargers go for 500 bucks on ebay and you need another thousand in parts- I would LOVE to put this on a 4.8 with a LS9 cam. however I cannot find ANY rectangle port heads!?!?

does anyone have a 4.8 or 5.3 with rectangle port heads? I did find 2.00 valve GM performance heads made for small bore LS1 but GM specifically says will not fit 4.8/5.3 and im not sure why when I see people putting 2.02s on 5.3s

or even bought one of these superchargers id love to hear the process involved with buying one of these recalled units..



blahhh sorry for the mouthful appreciate all the help I can get!!
-Dane

 

The rectangle port heads have a wider valve spacing, so even at 2.00", the intake valve is probably still too close to the cylinder wall on that teeny tiny 3.78" bore.

There is a guy in the FI section (I think) that's attempting to make adapter plates to put the LSA blower on cathedral heads.

 

Mast makes small bore rectangle port heads.

For the price of them, you might as well get a Huron Speed turbo kit and stick to your stock heads.

Or you can get a simple hotside kit from someone like KB Racing for $900 and bolt on a cheap turbo.

 

The exhaust valve will hit before the intake.

 

You don't find them because they don't fit with the valve sizes as mentioned before.

Your best bet is to either bore out the current block to ~3.9xx bore size and used small bore LS3 heads or just get an 4" bore block and go with that.

 

thanks for the reply guys! ill look into the turbo kit and balance out best bang for the buck.


much appreciated!

 

any idea if the huron f body kit will fit into a g body?