My final results were less than expected 5 psi 360trq - 360hp
The dyno read a little higher 380trq - 370hp but Jason
At Extreme Performance had to take some timing out due to detonation
He was finding while on the street test driving. So I figure
360 360 is where I am about�

I called STS and talked with them and they advised me the
Low numbers could be from the fact the turbo I have was modified. The
Turbine wheel was clipped and lightened. I purchased a used kit
From Texas rear Turbo�s Owners son . They were experimenting
with trying to make boost while stalling the car and they achieved
what they were trying to accomplish from what I understand .

I understand clipping a turbine wheel will definitely hurt the overall
output or efficiency of a turbo. But maybe at 5 psi it shouldnt matter
?!?!

Also STS advertised that a STS system should only be dyno�d on a dyno that has the ability to add load They advised that the extra load needs to be there so they can tune The turbo properly because it is load that makes the turbo respond . The guy at sts advised that the dyno that cannot apply extra load would make the turbo Not ouput as much as it should because it would overcome the base load that was set billy at trt advised me the same.
The dyno at extreme doesn�t have that capability but Jason didn�t really
think that is what the problem is.

The turbo makes full boost 5psi on the street at around 3200 rpms
And stays at 5 psi all the way to when it shifts

Jason at extreme really made my car run smooth and it really performs well
I really think he is good at tuning a car . My car responds like it should
And it runs like a Virgin out of hell. The air fuel is right where it should be
All the way through the power band. I really don�t think you could find anyone better To deal with than the guys at Extreme Performance in Oklahoma city.

One of these days when I have more cash I can figure out whats wrong with my setup It could be crap gas form shell , it could be my modified turbo , it could be the type of dyno that was used in tuning my setup . it could be that I need to run more than 91 octane .It could be I havea 1998 z28 with a auto trans and its not going to make good numbers.
I wish I would of dyno'd it in its stock form to see where I was at when I began.

But my car runs good and it moves Out a whole lot better than it used to . I think I should of listened to Jason and Robert At Extreme Performance and just put a camshaft and some heads on my car . Or I just could of Put a nitrous kit on my car and saved a whole lot of cash adn got the same results. Well I tried some thing different And found that it really is turning out to be a pain in my rear instead of the fun I was hoping for.

My opinion of the sts kit . It goes on relatively easy and lots of people are having great results! It sounds killer when yah get on it and I wouldnt advise buying one with out getting one of texas rear turbos front mounted intercooler kits. But Don�t drive through 12� of water ! and you definatley lose some ground clearance but no worse Than long tube headers. If your only going to run 5psi go get a nitrous kit �.

My opinion of Texas Rear Turbos Billy has been great to deal with and he made sure the used Setup I bought from his son was a complete setup and I got a good deal on it 3500 for a Sts kit and a front mounted intercooler setup dual stage boost controller and some new silicone hoses,clamps where it was needed!
I just wish that I knew the turbo wasn�t from a sts setup at the time of purchase . I assumed it Was by the way the add read and that it was modified to be better. not a totally different turbo
Here is the link to the add


https://ls1tech.com/forums/forced-induction/338708-f-s-sts-extras.html

But then I found this

https://ls1tech.com/forums/showthrea...tturbo+clipped

A posting by trturbo
We just had some work done on my sons turbo to see what kind of difference it made. Damn, it rocks. We had the turbine wheel blades clipped 7.5 degrees and lightened and we had the inside of the compressor housing polished. With the work done to the turbine wheel, we tried a .70 turbine housing.
http://www.trtturbo.com/images/misc...bo_pics_004.jpg
Look close to the compressor wheel on the Garrett.
http://www.trtturbo.com/images/custom_turbo_002.jpg
The compressor housing was machined for a 60-1 wheel; had alot smaller, 46 I think.
This is on a '94LT1 car, stock except for a gutted cat and 2500 stall. It has the basic STS kit on with one of our FMIC kits. Before, it wouldnt stall into boost very well, but now it will stall into boost in a hurry. I didnt think it would make that much difference, but it does.
The car feels much better starts boosting alot lower and pulls hard all the way up.
http://www.trtturbo.com/images/custom_turbo_001.jpg
This turbo started off as a crappy $250.00 used ebay turbo.
__________________
'02 Formula, 6sp, SOM, SLP ram air h.o. hood, LS6 springs, Shaner S2 throttle body, rear mounted turbo,
412/451 @5psi.
Texas Rear Turbos
Your Dallas/Fort Worth STS power dealer
We have OBX intercoolers!!!


I really was kind of pissed when I first found this but I didn�t buy the setup
From TRT I bought it from his son we just met at trt in texas so I could pickup this setup. And this is the turbo I now own and its for sale if anyone wants it! its a great turbo from what i understand!

Billy the owner of TRT was a great help to me when I was installing this system and he Made sure to let me know that he wasn�t the guy selling this system to me.
He has a great front mounted intercooler kit that really works well!


My opinion of the guys at extreme. I worked as a auto tech for ford for ten years before I burnt out on wrenching for a living. They do quality work and they are very trust worthy. I think Jason Is a excellent Tuner and Tech. I think Robert provides great customer support and keeps good contact with you while your car is there. I didn�t get to talk to abel but he allways looks busy and hard at work just like Jason and Robert always busy but not too busy to talk to yah.


I am hoping to buy a GT 67 gt 70 turbo sometime and making the power I am after 400/400

 

Yeah, man. Don't give up on FI, but you really need a bigger turbo.

 

The proper load on the dyno will produce results higher than what you have. That same turbo made 350/430 on a stock LT1.

 

Solution:

Get a bigger turbo with new 918 valve springs. Have Jason tune it on the street only. Strap the car to the dyno and go to town. Dyno #s are nice, but not end of the world.

Do you have an aftermarket converter in your car?

 

I have a yank convertor but its not installed yet.....

where did you order your t-70 from ?

 

The guy who made my rearmount(1320 on the LVfbody.com board) is a dealer. He is the one that made my kit, its not an STS, but his own rearmount with a lot more options and easier on the ol' checkbook.

I'll be coming thru OKC around the 19th and I'll be at Extreme..feel free to stop by.

 

yeah let me know when youll be there with your car!

I want to check it out!

does this guy have a web page? that made your setup?

 

No, he does this stuff on the side. He works on everything from old school stuff to the new stuff. He does have LS1 tuning ability and has totally redone the STS setup on one car already(Zombie). I am the 3rd person for a FMIC and first stab at a rear mount kit from beginning to end.

check some of Jon's work out

 

Matt, do yourself a favor before you sell it. Take it somewhere that will load it better and the numbers will be better.
We have used a turbo like that and made 560rwhp too. The power is there.
Also, keep in mind that no dyno will load like the street and therefore your tune will be different on the street. That is one reason a wideband is always a good investment.

 

Not true. A Dynapak will load like the street, heck you can make it load harder than the street if you want.

 

I am a little puzzled at the 5 lb boost level, when you have a boost switch and an intercooler. You should be good for 10-12 lb of boost with that setup. Of course, you would have to insure that your fuel system will handle it (injectors, fuel pump).
I am running an STS on my LT1 and get a reliable 5 & 8 lb of boost (boost switch) without an intercooler.
Personally, if I had it to do over again, I would also take another route, the STS is a pain in the buttocks.

 

I found a place here in okc that has a dyno
that can put load on it while its running
they also say they can provide a wide band o2 tune.
and that they have to weld in o2 bungs to do so properly
this is the place.
http://www.hpracingokc.com/ShowRaceCars.htm
they are right by my house so im going to give it a try before i give up on
the turbo ...
I just hope im not chasing good money after bad
I will try jasons tune on the dyno over by them and see if the number are different.
Whats the worst that could happen

 

98Ztwentyeight - check yo' PMs

 

I just read that link, and it says the turbo was modified. what add were u reading?

 

I saw the setup on billys son's car... it was gutless without the turbo... I went for a ride and can vouch that it spools nice... LT1's are weak sauce anyway... but I am sure you know that. My understanding is that clipping it should help with lag... also it is lighter and should spool nicely. IMHO you need to up the boost and you will be happier. I am sure it is not out of efficiency. Also a clipped turbo may spool nicer... yet you will lose some of the effectiveness of the amount of air being pushed with less surface to push it. on such a small turbo does this sound like a good suggestion? Meanwhile... Billy... still waiting for my 05 GTO (stay in business... i am comming)!

edit:... above all.... get a higher stall!!!!

 

Clipping the turbine wheel will make the rotating mass lighter, but now you have dropped the efficiency of the turbine wheel. Just like Jose said on that 2nd link above.

Not to mention, LT1 and LS1...both are good engines, but different animals. LS1s breath much better stock/stock-mod/mod and a T60 may work on an LT1 but will not work as well on LS1s.

What are the specs on this turbo btw....I mean, before the clipping/polishing.

 

I know it was modified but I didnt know it didnt come with a sts kit and its not a turbo from sts is my point!

 

THE SPECS~!
thats what i have been asking billy from trt for and i really havent gotten a exact answer..
Its my understanding after the fact. that it was bought off a ebay auction . It has a .70 turbine housing and .70 compressor housing that maybe a 45 size wheel was init and they bored out the compressor housing to except a 60 size wheel just like the stock sts turbo. and since it was bored out the inside of the compressor housing is polished .. the turbine wheel was clipped and lightened and the .70 turbine housing fit the best .. the compressor housing is sorta polished on the outside. the center housing is new and the center housing has provisions for water cooling.
so basicly its a mutant turbo sorta that worked well on a lt1 and might be working well on mine well see when i goto the dyno that can put load across it. I just wish all of this was explained before or at the time of purchase then I may have walked away from the turbo and made a offer on the system. I asked that question is this a sts turbo system and billies son told me yes. that would make me assume it is a sts turbo?!?! he advised
me he was selling this system so he could by a house

 

these are my current mods
I have a 1998 z28 with a sts rear mounted turbo setep, a obx front mounted intercooler setup, 42# flow matched svo injectors, stainlessworks cat eliminator, granatelli fuel pump "walbro" , The turbo is a garrett To4e with a 60-1 compressor wheel and the inside of the compressor housing has been highly polished. The turbine wheel has been clipped 7.5 degrees and lightened to bring the boost in sooner, Maf relocation kit, 160 thermostat, 2001 cast exhaust manifolds that I gasket matched, thunder volt wires, stock trans running a fluidyne cooler with a cooling fan and 323 rear end gear. and mobil 1 oil. Im going to run it at 5lbs for now on 91 octane