hello all, this is my first post on tm.com, and i am looking for help on deciding what turbo will suit my needs best.


the turbo kit will be a truck manifold LS1 with a sungle turbo. stock shortblock at first and will be a street car. with the stock block in place i want roughly 550 or so rwhp for as long as it will last with a proper tune. with a built short block looking for around 700hp. this is just a little background on what i "want" from the dyno.

some of the turbos that i am looking at are

MP T70(i am not sure if this turbo will hit my final goal of >700 rwhp.

MP GT45 (i am not real familiar with this turbo)

I really like the prices on those two turbos and finally the T76 GTS is of course my third option. i feel that this turbo will allow me to reach my goals, but is a little more expensive.

What are your opinions.

Thanks
Louie

 

If you keep the displacement below 360 then the PT-76GTS will operate phenomenally, if you bump it up to 383 or beyond, then look for a PT-88.
issuez

 

T76 GTS would work well.

 

If you are interested i have a new pt 88 for $1400 plus shipping.

 

Blue T, thanks for the offer but for now i think that i am going to go with a T76GTS.

If anyone has one of those for sale id be interested.


Also does anyone know where the best place to buy mandrel bent piping from?

Thanks
Louie

 

I had a T66 on my car at first... and made decent numbers, the graph is on my rice etr webshots. I have since redone the kit and now have a 76GTS on the car....still with stock long block. The turbo spools very nicely, would be even better if i had a stock cam in it. I should be posting up dyno numbers this Saturday if everything holds together.

The two places i bought cheap mild steel tubing from was Summit and JC Whitney.

 

one of the people that advertise up top have the best prices on mandrel bent tubing i have ever seen. i ordered from them today. it is a yahoo store i believe, but the prices are ridiculous.

Louie

I am honestly even considering that T88 now so i have room to grow

 

I think you should hang with the 76 for now...

 

A while back, Jose at Forced Inductions did a back-to-back comparison of a 76GTS to the 88 on a 355 LT1. The 76 made 987 rwhp and the 88 only went up to about 1010 rwhp at the same boost level, but spooled up much later and made less peak torque. Also, the 88 is physically much larger than the 76, so fitting might be an issue.

 

yeah, thanks guys. i have heard from you guys as well as others that the 76 will be a much better option.

So a 76gts it is.


i have it inm y sig, but if anyone knows of one for sale i am interested.


Thanks
Louie

 

PM turbocobra he may have one for sale.

 

That's true, that's why the 76 is better on less than 360 ci, preferrably something around 331, but beyond 360 the backpressure becomes an issue and the PT-88 comes into its own. Just depends on the displacement.
issuez

 

I dunno. . . I lost 30 rwhp when I switched from 383 to 363 at 13 psi with the 76GTS. Lost more at 20 psi.

 

I think the cam selection has the most to do with how a turbo acts on any cubic in engine.I ran a t66 on a 235 in engine that made 541 hp at 20 psi.I think that is a large turbo for that small of a engine but I think it worked well because I had a combo that was designed to work to gether.Also do you know if Jose changed the converter in the car to work with a 88?

 

so much misinformation here
at the 987rwhp the 76 was just about done, Jose told me that the 88 had more in it even at 1010rwhp it also did a better job at sustaining the boost where the 76 dropped off. The compressor sides of the 76 and 88 are the same size, the exhaust housing on the 88 is larger, oh also the center section is a little bit bigger as well.
At the time of the test the 355lt1 was on a T56, since then the owner switched to a Th400.
Also the test both turbos used a 3" downpipe, im sure if he would have had a 4" downpipe on the 88 it would have helped some as well, or even a 3.5" on the 76.

 

What, exactly, did I post that was incorrect???

The fact remains that on a 355 v-8 and <23 psi boost and 1000 rwhp, there is no advantage to switching to the 88. The 88 is also physically larger. And I'm not sure why a transmission swap after the fact is relevant here.

Mike

 

on how saying the PT88 only makes 23 more HP then the t76gts. the 88 had a bit left in it.
sure the 76 will spool up faster, then the 88 will make more boost, and be able to run a faster time.
if you want more then 1000rwhp then youll have to do an 88.

i mentioned the transmission to give the people an idea of fwhp, a t56 does not eat up as much power say as the th400 does, jsut ot have a ref point in there.