Hey guys,

First of all i'm new to the forums, so hello on that aspect -



I purchased a 1998 R34 GTT at the start of this summer, it came with the following performance mods.
410WHP currently @ 16psi.

--RB25DET--

GT3582 turbo
FMIC
Fuel Rail
Rad
top mount exh manifold
straight pipe
front facing intake plenum
340 lph fuel pump
kelford 260 cams
38mm ewg

As fun as it is when the car comes into boost, the turbo lag has me barely being able to come into boost during my daily driving. I've done quite a bit of research, and although there are always arguments for each side, I am curious on what your opinions are on which turbo would be best FOR MY SETUP.

After talking to my tuner, he had said he would recommend the 3071r as it would do an 'honest' 400whp at 18psi. My worries are the possibility of going 3071 and having a significant loss of power, not achieving what his thoughts are, and kicking myself for not going the 3076r route. Realistically I am planning this to keep my current mods moreso long term and not do much more power wise to the car.

I know regardless I will be diminishing quite a bit of turbo lag compared to my current setup, but I would generally love your guys input.

I guess this is kinda old, but since I'm here...

Firstly, GT35 is a beast and I believe will make substantially more than 400whp. I imagine on a fairly stock RB25 it will lag some. But also, what ECU are you running? The mapping could compensate a little bit. 3076 will comfortably make 400whp, and I've heard it spins up pretty well - I think that is what you want. I would imagine with cams and a good mapping it would be very nice. 3071 is certainly smaller - that is what I have (or at least a Garrett variant). If you want response, this will obviously spin up the fastest and provide bags of torque. Not the same top end as a 3076 but seriously do you need to use 400whp on your daily commute?! I think if you give it a load of boost, 3071 will still make close to 400whp.

I'll add that 3071 and 3076 come in Gen 2 versions (maybe what your tuner is talking about) that seem to offer considerably efficiency, with some extra top end, so maybe a Gen 2 3071 with a decent sized exhaust housing would suit your needs.