GT3776 Twin Scroll Turbo

[band-aid]

I have been doing some searching for a good turbo with decent spool times for a series one RB25DET. The problem is I am new to turbos upgrades, but not new to turbo cars. I found a GT3776R for $937 at Z1 motorsports:
http://www.z1motorsports.com/upi/produc ... 2151a97611
I think it's on the big side of street-able turbos, but since it's a twin scroll would that help the boost time. I would like something that comes in around 3,500rpm or less, but can support up to 450hp without breaking the bank. I know spool time comes down to supporting mods and tune, but I was curious whether or not this would be a good candidate. Thanks for any info one of you gurus may possess.

[ItzGenX]

That thing has a rather large turbine side mated to a small compressor. If you want 450hp at the wheels, then you'll have a major problem doing it with that turbo. The compressor map tops that thing out at 48-49lb/min of air at around 68% or less effeciency at pressures over 1.5 bar. 450hp at the engine MAYBE, but not at the wheels with that turbo. The journal bearing and abnormally large turbine side compared to the compressor side will lead to a higher rpm boost threshold. This thing will probably come on at around 4-4.2k rpm @ 1 bar. A GT3076R would suit you much better (450 at the wheels is realistic with it, although at the top of its lungs). It should come alive sooner than the turbo you are questioning too. The GTX3071R would be your best ultimate response turbo for your needs and still push the power levels you want at the wheels. Remember, the turbo majorly effects how the engine acts and runs. Cheaping out there will just end up making you want a different turbo. Buying another turbo to replace your regretful turbo choice will often cost you more in the long run.

[boostedh23a1]

Im shooting for 525ish whp on my rb26 but im trying to hold out for the borg warner efr.

[band-aid]

Thanks for the info guys. I think I am going to go with Precision Turbo 6262 with a twin scroll compressor and exhaust manifold. I talked to some people about it and the consensus is this should give better response and still be able to hit my goals. I have also seen quite a few Aussies with this and with very good results. I still think it might be a little to much for what will be mainly a "street" turbo. It's rated at 700+ hp I guess we will see in a few months.

[boostedh23a1]

Keep us posted, I want to see some RWD whp numbers with that turbo too. Most of them are rated at the flywheel.

[ST240]

Let me tell you if you're going with the 6262 go with a BIG turbine housing. I ran the T4 .59 (~ .68 T3, too small, i know) on my RB30 and it was pretty choked. I now have the T4 .86 twinscroll, which might be like a 1.06 T3 which should be a lot better. But I am still worried the turbine will run out of puff before the compressor does.

I'll keep you posted.

[band-aid]

ST240 thanks for the info. I don't think I will have any choking issues with the tune I am looking for. Sadly, I won't be able to start the build until later this summer as I am still deployed. I look forward to seeing some good numbers from your setup.