Clean94Z

iTrader: (5)

Ok a friend of mine has a fun lil project ls fox swap he is planning.

He has a low mileage gen 4 4.8 shortblock that he wants to use {no he does want a 5.3 or 6.0}. He wants to go carb/nitrous with a TKO 5 speed and see what it will do. He wants to stay budgeted!! No crazy hi-end parts.

My thoughts are 862/706 heads ported and milled with .040 cometic head gaskets to get the 9:1 comp up in the 10's. I read where some people take .035 up to .050 off them.. sounds crazy!!

Looks like the 4.8's like cams in the 220-230 range. Will probably talk to someone about a custom grind for the carb setup.

Will probably have a 200-250hp shot on it.

Any thoughts or suggestions for this 4.8 carb'd setup?

Mercier

iTrader: (15)

Does he want to stick with the 4.8 for the short stroke and higher RPM potential? I've thought it would be neat to bore a 4.8(you can go out to that of the LS1) and get some used factory 5.7 pistons. You would end up with the short stroke and high RPM and about a 5.0 to 5.1 displacement I think? Basically a 7500RPM "5.0" in a 5.0 Mustang and cheap. I've owned a lot of Fox bodies in previous lives. Sounds like a fun project.

BTW, I think at least one of the reasons why some guys get away with a lot of milling on 862s is that the older 5.3s have dished pistons and allow for more PTV clearance. Stock 4.8 I believe actually have flat tops and therefore higher compression already..but potentially less room for milling further.

Clean94Z

iTrader: (5)

Yeah is not looking to rape the world!! He wants to rev it 7k, probably some 4.10's and bang gears!! He wants the reliablity and strength of the LS motor. His goal is 10's on bottle!

Yeah we will need to check piston to valve clearance to see what room he will have! This motor has FLAT tops but is only 9:1 with 64cc 799's. Want to get the comp up as high as he can.