4.8L Turbo Build

[1bad396ss]

Moving along with my 4.8L / 4L80E Turbo project for my 68 Short Fleetside.

I have a couple of questions for anyone who has picked up a nice drop out LS type motor for these builds.


1. Top Ring Gap: researching this topic; many people open up the stock top ring a bit to allow for more heat expansion under higher boost levels. What is the recommended range for this gap? At what power/boost level is this necessary?

2. Rod Bolts: when going for high revving/boost I understand many folks swap out the stock rod bolts for ARP. Do you simply remove the stock bolts and swap in the ARP's to their recommended torque (not worrying about end size etc)? At what power/boost/RPM level is this necessary?

3. Head Studs/Gaskets - it seems like a lot of people are throwing in studs and new gaskets without any machining of the head/block. Is it common practice to ever just swap the bolts for studs without lifting the head and gasket (although that seems risky). I understand the LS9 cam is a good choice / any other good turbo cams with street-able manners recommended. Are the guys just swapping without machine work just cleaning mating surfaces and moving on? At what power/boost level is this necessary?

4. Fuel Rails - I am running an in-tank Aeromotive A-1000 pump etc. Can someone please recommend a good set of rails to use on the truck manifold and what injectors are being used (not worried about flow ratings / just what companies' products are preferred for quality etc)


I have the motor/tranny/harness etc all cleaned up and ready for the next stages. Power goals are kind of open ended. Currently looking at Borg Warner S475 as well as a Precision unit (sticking around 76mm on the turbo). I would like to throw down 500 rwhp daily and crank it up just when I feel like it. 99.9% of the time, I just want a nice driver that is a bit ignorant when the go pedal is mashed.

I always appreciate anyone's help or advice. If you have any good links, feel free to pass them my way.