Gtx gen 2 3071 or Gtx gen 2 3076

Has anyone used the above turbines and any diff on the spool ?

Thinking to shift from t3 2871 gen 1 ( .48 A/R) to either of the above..

T3 or v band?? Now the usual debate on this but my goal is to increase spool or at least maintain same as my current turbo but increase a bit the hp outcome at upper rpm range.

0.63 A/R either type i use..

Your input will assist, thanks

Boosted Cycle Perf

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.48 is WAY too small for something that can turn 11k rpm.

The 3071 has a small turbine so you’d need to be looking at a .86. The 3076 in a .63 will do you real good. I just tested a 3071 .63 last weekend, so I can tell you first hand the turbine is too small for that ar on a Busa.
I have an RCC ultra kit and the turbine is garrett customized..

The spool comes to abt 5000 rpm and full boost close to 8000 rpm

Just do not want to go for big turbo as i am running on pump gas ( 100 octane fuel) and can boost no more than 1.3 bar ...actually i have tested on dyno on 1.5 bar but now i have reduced using AMS to 1.1 bar...

Some guys go for bigger turbo as they are planning to use race fuel and see some good results..having abt 400 hp on pump gas but with good acceleration is what i want..

The 3071 was t3 ?? What results you saw compared to your previous one?
Something last, using 3076 with .63 will fit inside bodyframe as my current turbins does and keep the stealthy look??or i have to do mods

Boosted Cycle Perf

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Yes, T3.

The 3071 had too much back pressure. So much that it would hate 3x what the spring was rated for.

Based off of what you said your current turbo makes full boost by, it sounds like you have a 35R. A 3076 is smaller physically.


Something last, using 3076 with .63 will fit inside bodyframe as my current turbins does and keep the stealthy look??or i have to do mods
hey Big PK.... nice to see u got here... from the "other" forum... these are the guys I was telling u about.... the EXPERTS.... BOOSTED... and POWERHOUSE.... they are the best..... builder and tuners.
Hi Ali, for some reason i could not register to this forum for almost a year..i do not know why maybe it was the settings of this is nice being part of this big turbo company !!!

I have the RCc ultra kit rated 430 hp on race fuel and 380 on pump bike is currently running on 1.1 bar close to 355 hp on tight dyno ( not dynojet) with midpipe , muffler installed and filter inside body frame / side fairing..

It is not gt 35 ..this is stage 3 RCC mine is ..0.48 T04 50 trim which is very close to 2871

I am very confused whether it would give me any benefit to install a gen 2 3076 since i am not using race the limit of 400 hp would be same either turbine .

Prior going to replace the turbine, i am thinking to use dump pipe and increase the boost to 1.3 or 1.4 using Thorco for a bit of safety and see the mid pipe is 60 and muffler 65 so it is not reducing the output enough...once i remove the muffler the spool is better i think

Boosted Cycle Perf

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Either you have a much larger turbo then you think, or your tune is so far off that it’s causing the turbo to be lazy. To go Boost positive at 5k and full boost at 8k sounds sounds exactly like every 35r bike I’ve ever tuned. Rcc never offered ANY turbo with a .48 ar. It’s just simply too small. The current stage 1-2 turbos are a 76/64. They go boost positive by 3k and full boost by 6k on a lowered compression engine.

What size in the inlet of the turbo? What’s the diameter of the tube of the exhaust?
I will check...richard told me it is 0.48 AR and my builder said it is close to 28 71

Richard told me it is To4 50 trim
Think it is 50/56 but need to check again

Mine is RCC stage 1 ultra kit
21 psi on pump gas with muffler and midpipe ..AFR rich close to 10.8
Compression is about 9

I did not have time to check the diamensions..will do this shortly

Boosted Cycle Perf

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No need, that’s definitely the 76/64 stage 1/2 Garrett turbo.

That’s way too rich, specially for an Intercooled set up. Honestly you won’t find a lower rpm responding turbo then that. With as rich as the tune is that can cause that turbo to not be so responsive. With 9.5 cr, that should be at full boost by 6k.
Yes it is too rich, i agree.. the tuning made with temps close to 15 oC and during summer the temp may reach 40 oC..thr tuner said he preferred to stay rich but i think as you it is well too fat...the summer will end up close to 10.5 with such temp..

So no need using a 3076 .63 you think?
I am using AMS 1000 and have now set up the boost at 1.1 bar max on 5h 6th gear..

I will increase the boost lets say to 1.3 bar and i am thinking to use the dump pipe or just a midpipe withou muffler close to 70 mm this small change may assist to postpone the usage of another turbine for a while and reconsider my options.. using a bigger turbo might need other mods as well and all may not fit inside the fairings etc thus not being able to keep that stealthy look

Another alternative may be using a 2nd map with race fuel and gain some good power close to 430 hp

I just feel the response is not scary and the bike is running way too smooth..with 3rd gear i see no wheelies at all..i am using macintosh 3 inch more than stock

Do you guys use Thorco as octane booster or it is useless ??

Boosted Cycle Perf

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The turbo you have right now is is essentially a journal bearing GT3076. The only benefit going to an actual GT3076 is ball bearing. It makes Boost at the same rpm as a journal bearing. However the point of going Boost positive to full boost is decreased.

I can tell you however something is off on your setup of that turbo is coming in as late as it is. That fat afr isn’t helping. Other things that will affect response time is ignition timing, and where your cams are degreed at.

As far as race fuel, or fuel additives, you’re wasting money if you have an ultra intercooler. On a stage 2 ultra like what you have, you can max out that turbo on pump fuel. It will make right at 420-430 on pump fuel even on a conservative tune. The only time I suggest race fuel with that set up is if you’re going land speed racing.
Forgot to say i paid some extra money and my turbo is ball bearing and not journal bearing..this was sent from RCC

Cam timing is 106/106 or 105/105

Ignition timing dont know..

Will reduce the AFR and see the results..with almost 420hp will be fine on pump gas..

Frankly speaking, Richard told me it is not 3076 or even 3071 but similar to 3071..once i will pull out the fairings and install the dump pipe i will measure the turbine to be 100% as we had the impression it is smaller than 3071..

My bike as is now View attachment 1594253


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