GT3071 on a 1HZ (1 Viewer)

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I bought a home brand one recently for my 1HZ and everyone went woah! waaaay too big, I was able to change the order and ended up bying the GT2871 which I'm led to believe is about as big as you want to go. My understanding is that bigger turbos will still work, you'll just lose your spooling speed (bottom end) and will be slower to the top (Top end) and less responsive. From what I can tell you want to keep your turbine compressor down around 0.60:1 for a quicker spool, but there are a lot of other factors and a lot to learn. I just bought the GT2871 to suck it an see, I'm happy with it. The cost continuum is from $500ish - $3000ish so there are plenty of options out there. The more you pay the more you get in terms of have a crack (me) vs matched/guaranteed performance. Longevity is also a factor in some of the earlier knockoffs but the new ones seem ok so far. So it's all relative to your pocket depth and your desire for low boost, responsiveness, top end roar and longevity. And your willingness to try things out for yourself.
 
Ok cheers I have seen 2 people with them on the internet and they have said they have got good results (180RWKW) but you don't know if they are making it up, I may buy the GT3071 first and try it if to big get the other. Have you put the GT2871 on yet or still in the build.
 
2863 is a good option to look at.

Do keep in mind that the stock ct26 turbine and the gt30 are quite similar.
Maybe a GT3067 may be a cool one to look at.
Guys rock them with patrols.....

There are better options out there though.
I'm currently working on something fun at the moment....
 
Whether you consider it good or not depends on what your criteria is.

Certainly from a peak power perspective especially when running quite rich (15-17:1), the GT3071 56 trim is about perfect for 2200rpm and up. Will make huge power. 230kW at wheels is feasible.

The GT2871, is initially more responsive (under 10psi boost) than the GT3071, flattens for a bit then comes on hard at 2200rpm with slightly higher afrs than the GT3071, then chokes in the high rpm - max ~ 185kW with sane compressor (56 trim)

GT2860RS is the best of the three, afrs are better (16-18:1), and up to 18-20psi. But, laggy unless rich. 150rwkw max using a 0.64 A/R exhaust housing.

A rich running TD42 Nissan maybe it's ok (to some), but a 1HZ... They need to be cool, 20:1 afrs min (in my opinion).

The GTX range is even worse than the GT range for diesels according to some of those experienced in fitting the Garrett range.
 
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Ok thanks Graham what does your BADBOY EXTREME and BADBOY compare to these.
 
It depends what AFR your targeting, but at 20:1 afrs, the BBX is far more responsive than a GT3071 and at the same low afrs (17:1) and boost will make about the same power.

Generally I would suggest a Stage 2 (called a Grunter Extreme) or Stage 3 (called a Bad Boy). A customer had 249rwhp on a TD42 with a Stage 2 (the GX). It was a rich 16-17:1 but that's what some people run the TD42 at. Boost response terrific. 20+ psi at 1600rpm or thereabouts. You won't find me reccomending such rich mixtures though except at very low rpm
 
Hi gbentik i was just reading and was wandering about the AFR on diesels you talk about 17:1 and 20:1 fuel ratios i was wandering how these translate to egts as this is how most of us tune our turbo diesels.

i can guess that 20 parts air to 1 parts fuel would have lower egts than 17:1 but how do you measure the AFR and conclude whether its safe or not? do you get these readings at full throttle max egts?

is it safe to say 650 degrees egt under full load has safe egts?

Thanks!
 
Hi gbentik i was just reading and was wandering about the AFR on diesels you talk about 17:1 and 20:1 fuel ratios i was wandering how these translate to egts as this is how most of us tune our turbo diesels.

i can guess that 20 parts air to 1 parts fuel would have lower egts than 17:1 but how do you measure the AFR and conclude whether its safe or not? do you get these readings at full throttle max egts?

is it safe to say 650 degrees egt under full load has safe egts?

Thanks!

Generally speaking 18:1 is the limit of safe and clean. Below that you start to smoke and by 16:1 you're putting out significant smoke.
EGT depends on intercooling. I still haven't fitted an intercooler (too many projects, too little time) and hit 750C with ~19:1 A/F.
My boost compensator needs a stiffer spring, it opens too soon (full open at 7psi) and drops A/F to ~15:1 for a breif window during acceleration. Otherwise completely clean.
 

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