After Searching throught various posts. I have come to a question that I wish somebody could answer for me.

What are the differences between the 50 trim t3/4 (non ball bearing) and the GT30R.

I know that the GT30R has more "potential" horsepower, but I am really more concerned about spoolup characteristics (as comparied to the stock turbo).


In simple terms, which one will spool up quicker, and how does that compare to the stock turbo spool?

 

So do you want a pre DSM turbo mitsu or your EVO?

That is kind of your question. I can't answer the spool question, I can anwser that the old garretts are largely crap, and if done by turbonetics they are largely unreliable crap.

 

wow holy misinformation batman

A full Garrett 50 trim setup has made over 500whp on pump gas and has put cars in the 10's on race gas. The new Garrett GT stuff is largely better at higher boost levels on leaded race gas. Spool time is under 4K using a 50 trim with a stage 3 hot side in a .63 a/r housing.

 

thanks AA for your response, but i'm still wanting to know what the spool up difference is between the GT30R and the 50 trim (non-ball bearing) one. Or is there no difference.

Yeah I have been reading of a 3600-3800 rpm spoolup for the GT30R, but I am just trying to figure out if the GT30R is any better.

 

GT30R should have full boost at around 3800 RPM on an EVO. Granted full boost on pump fuel is around 23 PSI so keep that in mind. ON race fuel I run the GT30's at 28-30 PSI. They make killer power but the other added feature is that they are much more efficient and much more reliable than the older T series turbos. Garrett does not make T3/4 anymore. Other companies do but certainly not Garrett. It is very very old design. Willa t3/4 make power? Sure it will. Will it be as efficient and as reliable as a ball bearing GT? Not on your life. On average a ball bearing center cartridge lasts about 4 times as long as a standard bearing cartridge. Lastly, you need very low oil pressure so if you go with G30R, make sure you make the feed line with the special 30-35 thou restrictor in it or you will have problems.

 

GT30 is not a specific turbo its a family of turbos including many wheel and housing combinations. That's like being asked what kind of car you drive. Then you answer its blue.

Boost level is determined by knock inlet temperature and compressor efficiency. There is not specific boost level limit on pump. I run 25 psi on my GT30 on pump gas. Please lets not spread more misinformation. Then this board already has.

Says who and compared to what? Again a GT30 is not 1 specific turbo. on pump gas a t3/t4 50 trim will *destroy* most GT30 turbos. In spool and power production.

 

I have to agree that I've seen t3-t4 turbos outspool any GT series turbo. A GT turbo performs better at high boost and requiring racegas, at those levels I believe that the more modern design will outflow the T series. BUt for anyone to say that the T-turbos are not efficient enough for an EVO is just ignorant. I guess a standard 16g oil cooled turbo that already IS in the Evo is archaic too?

 

A. All turbos are oil cooled. The 16g is oil and watercooled as well.

B. 50 trims are AWESOME turbos.

 

what I meant was non-ball bearing.

 

It's called "oil bushing", but its a good point.

 

Okay.. so let me recap:

GT30R and T3/T40e (50 trim) both spool under 4000rpm.
it appears that the t3/t4 will make more power at higher boost levels.
The GT30R is ball bering and the t3/40e is a sleeve bearing.
Also the T3/t4 appear to spool up quicker.
correct?

Now what i'm still confused at is:
1) using 91 octane? which would perform better?

2) Unline some people I'm lookin for 19-20 psi on pump (91 octane). Which would run better at those restrictions?

Optional question #3) Should i just keep the stock turbo and forget about replacing it?

Thanks again for all your responses.
SMS

 

First of all, forget about making comparisons between different turbos unless you know all the specifics of the tubos. You'll need to more than just the compressor trim.

But generally speaking, the only advantage the traditional Garret T3/T4 turbos have over modern GT-Ballistic turbos is availability and low price. This isn't to be discounted since there are many different sizing options that one can choose from when it comes to matching a turbo for his particular application. It goes without saying that a well matched T3/T4 hybrid will perform better than an ill-matched GT-Ballistic turbo. More modern aero, bearing and housing design will not make up for running an inappropriately sized turbo. This was especially the case a couple of years ago when GT-Ballistic turbos were largely unobtanium and very expensive.

But fortunately, things have changed. Recently, Garret Honeywell has put a lot of effort in getting its GT-series turbos more readily available, in a greater number of sizes/configurations, into the hands of the aftermarket. No suprise considering that these turbos represent cutting edge of Garret's turbo technology. Technology which grants the GT turbos a significant performance advantage over 1970s vintage T3/T4s which were originally designed for lower temp diesel applications. All things held equal, a GT turbo will spool quicker, offer better transient boost response, and do so more efficiently than a standard T-series turbo.

Currently, between the GT30 and GT40 families, there are enough turbo sizing options/configurations to find a very well matched turbo for just about any turbo application an EVO owner could want. If you're willing to pay the price (GT turbos are 2-3 times more expensive than standard T-series hybrids), there is no doubt that a GT turbo will perform getter than just about any other option on the market. Comparing them to the T-Series turbos of yesteryear isn't really fair, IMHO.

Regards,
shiv

 

Show me *1* GT turbo that has made more HP on a 4g63 on pump gas. With comparable spool then a t04E 50 trim in a 4 bolt ballistic turbine housing. Using a stage 3 wheels that comes out to a .63 a/r. Product description is wonderful, hard numbers and facts are another. My car using a 50 trim has made 437whp on Pump gas and gone 11.61@123 also on pump gas. What have you done on pump gas with a GT turbo?



Best of luck.

 

I am very happy for you. But how does our drag racing accomplishments with a GT turbo, on pump gas, in another car, in another system, prove or disprove the advances that Garret has made in turbo technology over the last 20 years? Yes, I suspect you'd be faster with a more modern turbo design. And I suspect any Garret engineer would feel the same.

Before we argue for the sake of arguing, I suggest you place a call to Garret Honeywells Boosting System group. I'm sure they can give you all the details/info/data you are demanding. I know for a fact that they have done a lot of *controlled* comparison testing between the GT series and standard T-series turbochargers that you are familiar with. I don't think many could accuse them of trying to pull the wool over the eyes of us consumers.

Regards,
Shiv

 

Why couldn't we? Garret owns all the right to the GT series while the T series is completely open to manufactur. They want to sell GT series turbos. For what its worth, I see better result with T series, but the GT series is not used as much, so its hard to say.