Why all the "big" turbo kits @ low boost

[DriftEightSix]

Originally Posted by King Tut

This guy knows whats up. All people seem to care about are the peak numbers. Give me quick spool, flat torque, and linear power any day.

How do I achieve this!?

[Boss Paco]

Originally Posted by DriftEightSix

How do I achieve this!?

Properly configured setup. Know your goal and build toward it. Ask an expert if you don't know how to reach your destination for assistance.

[cdrazic93]

Originally Posted by Boss Paco

Know your goal

Know your goal...like its going to stay in one place lol

[Boss Paco]

Originally Posted by cdrazic93

Know your goal...like its going to stay in one place lol

Maybe goal can be swapped for expectations?

[Coheed]

Originally Posted by TRD_07

Given all the dynos we've seen with the gtx2867r we know that this turbo works great on this platform but it seems like everyone is skipping the gtx3067r and jumping straight to a gtx3071 or gtx3076. Is this simply for the future proof overhead? The gtx3067r does have a little more room than the gtx28. I'm curious if anyone has tried the gtx3067r.

The GTX2867r has been used by many with good results, but the ns111 turbine is best suited to the 63r compressor. The turbine starts to choke when using the larger compressors, but on some engines it has decent results. It's certainly much better than the gt2871r! The GTX2867r is a pretty well matched turbo with lots of potential.

Likewise, the T30 wheel used in the GT30 is well suited for the gtx67r compressor, or even the GTX3071r compressor. But the turbine is overwhelmed by the flow of the 76mm compressor in standard 6 blade or the 11 blade form. The turbine is simply too small imho, and you'd be better suited to the T350 turbine for the 76mm wheel. The GTX3576r is a great turbo, with near perfect balance.

Managing the backpressure on these setups will help keep temps down, and the NA profile of cams will like the free-flowing exhaust wheels. It's my expectation and opinion that the GTX3576 with a .82 exhaust housing will be an absolute riot to drive and perform excellently. 600whp potential with great response.

If you are looking for the absolutely most responsive turbo for 300-330whp, I would probably suggest the disco potato. I haven't tried the GTX2860rs or the GTX2863r personally, but have seen some miatas with these fitted making ridiculous power for low boost and just nasty responsive.

[King Tut]

Originally Posted by DriftEightSix

How do I achieve this!?

Well the GT2871R in my Full Blown base kit got me a flat 250+ ft-lbs from 4100 RPM to 6500 RPM:



You won't find any of the superchargers producing a curve like that. This was achieved with around 12 psi of boost. A slightly larger turbo could probably hold the torque higher into the upper RPM range as well.

[diss7]

Originally Posted by Coheed

The GTX2867r has been used by many with good results, but the ns111 turbine is best suited to the 63r compressor. The turbine starts to choke when using the larger compressors, but on some engines it has decent results. It's certainly much better than the gt2871r! The GTX2867r is a pretty well matched turbo with lots of potential.

Likewise, the T30 wheel used in the GT30 is well suited for the gtx67r compressor, or even the GTX3071r compressor. But the turbine is overwhelmed by the flow of the 76mm compressor in standard 6 blade or the 11 blade form. The turbine is simply too small imho, and you'd be better suited to the T350 turbine for the 76mm wheel. The GTX3576r is a great turbo, with near perfect balance.

Managing the backpressure on these setups will help keep temps down, and the NA profile of cams will like the free-flowing exhaust wheels. It's my expectation and opinion that the GTX3576 with a .82 exhaust housing will be an absolute riot to drive and perform excellently. 600whp potential with great response.

If you are looking for the absolutely most responsive turbo for 300-330whp, I would probably suggest the disco potato. I haven't tried the GTX2860rs or the GTX2863r personally, but have seen some miatas with these fitted making ridiculous power for low boost and just nasty responsive.

There's a lot in this thread I disagree with, but I agree with this post.

I had a gt2860rs on my s15 and it was an epic street car. I swapped it out for a gt3076r and didn't like it at all. It's why I've chosen a gtx2863r for mine. The advice I was given was similar to the above, and that I should go to a gtx3067r if I wanted a bit more.

The problem is that responsive is so subjective. I glazed over a post saying that 14psi at 4500rpm is responsive; and for them that may be, but that certainly isn't what I'd call responsive.

Personally, I think there is a difference in what the term street car really means. To me, it's driving around the streets. To others, it's highway pulls.

[diss7]

I'll also add that this motor isn't snake oil. It is just a very efficient modern engine.

Sure, you might put a 600hp turbo on it, run it at 350hp, and think that it's responsive, and for you it might be. But you're kidding yourself if you think you have anything over a well chosen 400hp rated turbo making the same 350hp. The only thing the first example has is scope for later power needs.

I would encourage anyone that is seriously thinking of choosing a turbo to learn how to size one correctly using maps, and not take opinions from those running over sized turbos, who IMO are either giving biased opinions to justify their own purchase, or only interested in highway pulls.

[Ironsquid]

Originally Posted by diss7

I'll also add that this motor isn't snake oil. It is just a very efficient modern engine.

Sure, you might put a 600hp turbo on it, run it at 350hp, and think that it's responsive, and for you it might be. But you're kidding yourself if you think you have anything over a well chosen 400hp rated turbo making the same 350hp. The only thing the first example has is scope for later power needs.

I would encourage anyone that is seriously thinking of choosing a turbo to learn how to size one correctly using maps, and not take opinions from those running over sized turbos, who IMO are either giving biased opinions to justify their own purchase, or only interested in highway pulls.

Find me one 86 owner thinking about turbo options that drives around on the street below 4,000 rpm under WOT and pretends redline is 4500.

Drivability on the low end has NOTHING to do with the size of the turbo and you are severely mistaken.

Its like you're trying to re-enforce the idea that smaller turbos are better when it's already been debunked on this car. Better meaning more efficient power, cooling, driveline strain, driveability at low speeds, list goes on.

[jamesm]

Originally Posted by diss7

I'll also add that this motor isn't snake oil. It is just a very efficient modern engine.

Sure, you might put a 600hp turbo on it, run it at 350hp, and think that it's responsive, and for you it might be. But you're kidding yourself if you think you have anything over a well chosen 400hp rated turbo making the same 350hp. The only thing the first example has is scope for later power needs.

I would encourage anyone that is seriously thinking of choosing a turbo to learn how to size one correctly using maps, and not take opinions from those running over sized turbos, who IMO are either giving biased opinions to justify their own purchase, or only interested in highway pulls.

you've very, very obviously never actually tuned or even driven in one of these cars equipped with the turbos you speak of.

you simply cannot make the same amount of horsepower on a 'properly sized' 28xx turbo that you can with a 30r or 35r on pump gas reliably. i know this, from experience. and yes, this engine is remarkable in the way it is able to spool these 'huge' turbos. there is almost no perceptible difference in 'lag' between my 2867r and a 3076r. the 3582r doesn't add much on top of that.

and xx psi @ xxxx rpm does not effectively quantify how responsive a turbo feels. the t3/t4 hybrids build more boost at lower rpm than the gtx's (maybe, depends which ones you're comparing), yet feel far less responsive.

speak from experience. if you were, you wouldn't be saying the things that you are.

[mrk1]

I've done lots of research and not on forums, info straight from Garrett/Precision. I can read/plot maps just fine. In the end I still went with what in my opinion felt right. Because at the end of the day it's all personal opinion.

At the end of the day I purchased a turbo that is larger then I would have originally thought but that's the fun part. Learning, trying new things, take my head out of formulas and paper work, and just drive the thing. (Now if it would stop snowing)

No one has some great wealth of knowledge of what these motors will do so we are all just going on hunchs and guess's regardless of what the math says. Don't get me wrong I do my math homework but it's not the end all be all of decisions, the drive is.

[Ironsquid]

Originally Posted by mrk1

I've done lots of research and not on forums, info straight from Garrett/Precision. I can read/plot maps just fine. In the end I still went with what in my opinion felt right. Because at the end of the day it's all personal opinion.

Well said personal preference. But alot of what im seeing in this thread are people claiming big turbos arent drivable, a waste, unbearably laggy, etc.

I urge people in this thread please do research, I mean actual research, not regurgitated forum posts. Dont claim things you dont know about and please for the love of god dont over exaggerate or mistake low end power for low end city driving response, they are two different things. Oh and dont apply what you know about low compression turbo motors to this one.

[Boss Paco]

If you aren't running a 6466, you're a *****.

[spdbydesignchris]

Originally Posted by Boss Paco

If you aren't running a 6466, you're a *****.

That's why I run 2 on the GTR, haha.