twist3dspeed

I have a 98 z28 with a gm hotcam, ls6 springs, hardened pushrods, 1.8rollers, slp maf and lid, longtubes, slp race radiator core (thicker) and 160 stat, walbro 340 fuel pump, (no dyno or tuning yet i havent got that far). coming soon the built th350 in my garage with tci 3800 stall and the twin t3s that i got for a little more than $200 if they will work like I want. thats where i need the help. Keep in mind I know almost nothing about turbos. will they even work properly in a twin setup on the ls1? I DONT want to do any lowend work so i need to know what psi I can run stock. I only want a 50 to 100 hp increase and Im guessing 8-12 psi boost (I dont even know if those numbers are accurate).will my cam and topend work with the turbo setup. fuel upgrades? injectors? rails? boost controllers? bov? inter/after cooler? my buddy said something about low psi not being able to hold the boost thru the uper rpm's but he wasnt sure. Ive probly forgot a bunch of things but theres the start of my questions. thanks in advance for any and all help. Tony

jsetzer

You need to take a 2 week vacation and spend 23.5 hours a day reading every piece of material you can about turbos. This would get you about 20% of the info I have gone through over the past couple of years getting ready for my project.

This being said, don't be intimidated, just prepare for a lot of reading.

- Specifically which turbos do you have? I am using a set of the .60/.63 tbird turbos for my build. These or the GN turbos should work for you, if they are the .48 you may be wasting your time.

I know personally of a car - bone stock ls1 internally with injectors, tune, and @ 9psi that put a tad over 550 to the wheels. So your goals really only need @ 4-5psi.

Fitting 2 turbos, even t3s in our cars is not fun. I moved my core support and since you have a thicker radiator that makes for even more work. It can be done though - be creative.

Cam is ok for your goals. Longtubes will have to go (unless you want to do an sts style)

Ill get into more, need to know your turbos first.

twist3dspeed

compressor housing - garrett 409115 54 A/R 42
turbine housing - A/R 48

if that means what I think it does. this sucks. can I do a t3/t4 hybrid on these?

jsetzer

You could.... but as far as money goes with everything in it I don't know that I would.

Those would probably make your power goals, but do you really want to design an entire twin system to only gain 100hp? I think mine will make 550, but thats about the most air they can move.

Honestly if I was starting again I would just go with a single t76. Spools fast on a small block and should support up to a good 800hp if you ever wanted to rebuild for a lot of boost. You could always sell yours for what you have in them and pick up a single for a little more.

check out theturboforums.com - Its another message board. They have a junyard/diy section with lots of good info on builds with tbird turbos etc.

Mike@HTD

those turbos are off of ford turbo coupes. meant to be used on 2.3l 4 bangers. lots of 5.0 guys run those with great success but with your added cubes over them you will be running out of steam by 5k.

jsetzer

Mine are slighly larger so it may help a little, but I do expect to run out of power up top.

It can be a stump puller.

Wish I could find someone with experience. I have found a handful of 5.0s, but not really anyone running them on a sbc.