Which turbine size for gtx3071r?

[Sellout]

Originally Posted by diss7

A compressor working more efficiently, so it is outputing the air cooler.

The more inefficient a turbo is (eg as you fall away from the efficency islands) the heat in the air it is outputting gets higher.

Thats at least my understanding. I could be mistaken.

yeah, and? if both are making 350whp, which one is faster?

[cruizin01]

I ran a GT3071 w/ a billet wheel and a .63 tial housing to 28psi and almost 500whp on a VW 2L without it falling off up top. Obviously different setups and lower compression but I dont see you maxing a GTX3071 w/ a small exhaust housing at 350whp.

[DeBiase]

OP Since you have done extensive work on researching compressor maps. Which would you recommend for a great midrange (around 4K RPM) but also a good top end, as it will be primarily a street driven car maybe some track days here and there. I saw the 2867 map and am worried about over speeding the turbo if I try for too much airflow. Then again the mid range in the 3071 seems a bit lacking. Thanks for the input. All others are welcome to input and help me in my future turbo selection.
PS the non-X GT3071R seems to have a good midrange and peak efficiency. What do you think. Though I prefer to get a GTX.

[DeBiase]

And also about the higher heat from being out of the efficiency island does that only apply to the right of the efficiency island (over efficiency-island airflow) or does it apply to the left of the island as well (under efficiency-island airflow)?

[diss7]

Originally Posted by DeBiase

OP Since you have done extensive work on researching compressor maps. Which would you recommend for a great midrange (around 4K RPM) but also a good top end, as it will be primarily a street driven car maybe some track days here and there. I saw the 2867 map and am worried about over speeding the turbo if I try for too much airflow. Then again the mid range in the 3071 seems a bit lacking. Thanks for the input. All others are welcome to input and help me in my future turbo selection.
PS the non-X GT3071R seems to have a good midrange and peak efficiency. What do you think. Though I prefer to get a GTX.

GTX2867R for sure. 0.64 if you want best spool, at sacrafice of 7000-7500 fall away. If you want vice versa, got 0.86 exh housing, which will spool slower, but not restrict top end.

Originally Posted by DeBiase

And also about the higher heat from being out of the efficiency island does that only apply to the right of the efficiency island (over efficiency-island airflow) or does it apply to the left of the island as well (under efficiency-island airflow)?

I'm not 100% to be honest on this theory. But it would only be to the right, not the left. Left of the island its not hot, its probably more to do with aerodynamics and that sort of jazz.

[DeBiase]

Where do you see spool occurring for the 0.86 and the 0.63 for the GTX2867R?

[diss7]

Originally Posted by DeBiase

Where do you see spool occurring for the 0.86 and the 0.63 for the GTX2867R?

High comp FA20 will spool even 0.86 housing before 3500rpm. I see no reason to go to 0.63.

This is info I have been PM'd by someone who has already performed this comparison on that turbo.

[nelsmar]

Originally Posted by diss7

High comp FA20 will spool even 0.86 housing before 3500rpm. I see no reason to go to 0.63.

This is info I have been PM'd by someone who has already performed this comparison on that turbo.

Would you care to share the comparison between the housings? I would love to see charts if there are any. Especially if they were the 3071...

My new build is going to be around 10-11CR and i cant decide on AR... probably going with .63 though.

[DeBiase]

Ok cool. And what are your thoughts on the GTX3067? Does the 28 turbine limit top end performance at all? I am not certain but I figure that it is smaller so it will obviously spool faster but since it is smaller it will reach a level where it can no longer spin fast enough to continue to produce power. As opposed to the 30 which would continue to perform up high being that it takes less spins from the larger turbine to produce the same affect on the compressor. Btw thank you for your information and taking the time to respond. I very much appreciate it.

[jamesm]

i use a 0.63 tial vband housing on a gtx2867r and it hold boost (and makes power) right up to redline.

[jamesm]

Originally Posted by DeBiase

Ok cool. And what are your thoughts on the GTX3067? Does the 28 turbine limit top end performance at all? I am not certain but I figure that it is smaller so it will obviously spool faster but since it is smaller it will reach a level where it can no longer spin fast enough to continue to produce power. As opposed to the 30 which would continue to perform up high being that it takes less spins from the larger turbine to produce the same affect on the compressor. Btw thank you for your information and taking the time to respond. I very much appreciate it.

the 3067 is a horribly mismatched turbo. the 3071 even is. 3076r is where it's at if you're looking to go that big.

don't buy too much turbo for your needs. it's an expensive mistake and you'll regret it. as stated before, buy the smallest turbo that will reach your goals.

[diss7]

Originally Posted by jamesm

i use a 0.63 tial vband housing on a gtx2867r and it hold boost (and makes power) right up to redline.

Do you have a dyno and/or build thread?

Cheers.

[jamesm]

Originally Posted by diss7

Do you have a dyno and/or build thread?

Cheers.

yeah my first dyno is in the 'FI dyno' thread... and i've posted a boost log in a thread somewhere. i'll try to find it.

edit: found it

[diss7]

Originally Posted by jamesm

yeah my first dyno is in the 'FI dyno' thread... and i've posted a boost log in a thread somewhere. i'll try to find it.

edit: found it

Nice. Certainly comes in early

I think the 0.64 will become restrictive once/if you dial the boost up to 12/14psi; which is where I would look to run a gtx2867r.