07sick22

Im going carbed on a 99 z28 and was wondering how much hp the stock in tank pump will support and also will it work fine with a heads cam combo? also what size return line would you guys recommend off the Mallory 4309 regulator? and is there anything special that needs to be done to use the stock fuel feed line on the 4th gens? thanks

S10xGN

iTrader: (11)

Your factory EFI system should be OK for at least 450 FWHP as long as the return line is large enough to return the excess fuel. I'd go with 3/8" for that combo...

07sick22

thanks and I ended up getting 1/2 for the return just need to figure out how im going to plumb that back into the tank