ProjectS130

Thanks, that was kind of the way I was leaning but was concerned a 1.01 or 1.06 A/R would move the boost threshold too far to the right on a build like this.

Hey guys. New member here, but have been lurking for a while and reading (and re-reading) this thread and the other RB25-related forced induction threads. I'm building an RB25 to drop into my 280ZX, and have nearly every bit of my build settled aside from the turbo. Goal for now is 500WHP on E85, without having to turn the boost up too high to maximize longevity/reliability (like 20-22psi), strong mid-range while pulling hard all the way to redline. It'd be a street car ~95% of the time and I'd keep the limiter 7500rpm or lower. Doesn't seem too lofty a goal and I've had my eye mostly on the Gen2 GTX3076R and G30-770. @Lithium posted a graph in here a while back matching these two on a stock RB25 and the G-series seems a clear winner, but I've seen several posts now in different forums about G-series underperforming or failing due to overspeed, which gives me pause. It seems like maybe a bad rap brought on by early failings but....I don't know? Wondering if anyone's had any more experience with these in the recent months; I'm just not sure whether to stick with the proven Gen2 GTX or the newer tech. The rest of my build for detail: Built motor (9:1 CP pistons, Manley rods, etc) Kelford 262/262 9.3mm lift cams & valve spring kit 1050cc injectors, 340lph pump, E85 6Boost T4 twin scroll manifold, single 50mm WG Plazmaman upper plenum, stock lower CD009 trans 🤙

Ok, so some background first: I'm building an RB25 to drop into my '82 280ZX (or more accurately, machine shop is building it). My goals aren't too lofty; I'd like a really quick street car that I can push hard when I want to, and not worry too much about blowing up. Looking for max 500WHP, good response, full boost by ~4k RPM and strong all the way to ~7500RPM. To this end I've got the machine shop building it with forged pistons/rods/etc. Parts list: CP 9:1 86.5mm pistons, Manley rods Kelford 262/262 cams and KVS25R spring kit AEM 340lph pump ID 1050x injectors Plazmaman upper plenum LS1 coil conversion EMU Black standalone E85 Left out some stuff I'm sure but that's the gist of it. I'm pretty set on a Garrett G30-770, seems to suit my goals pretty well without having to turn the boost up too high. Along with a solid tune on E85 it should be no problem to hit 500 at the wheels from what I've read. My question is, would I be better off with an 0.83 turbine housing with a T3 or V-band flange, or a 1.01 T4 twin scroll? If I'm chasing good mid-range power and full boost by at least 4k, without having it choke up top? I'm looking to buy a 6Boost manifold and want to make sure I get this right on the first try D= I've read through the RB25 turbo upgrade thread (not every bit of the 61 pages but, mostly...) and still can't get a good idea of the answer here. A twin scroll housing helps with spool time, but does it help enough to (mostly) offset the lag introduced by going from an .83 to a 1.01 A/R? Thanks =D

These are from when I got it last year. It looks decidedly less nice now, after pulling the front bumper and giving it a nice reverse rake (by pulling the drivetrain).

Thanks! I do hope it ends up as rad as it sounds, I've got a long way to go.

Hello from the states 👋 New here, but been interested in Nissans on and off for about 20 years. As a broke college kid I had an S13 coupe, and managed to scrape together enough $ to do an RB20 swap. This was ~2003 before the drift craze made everything expensive and destroyed all the S-chassis cars. It was fun but I was broke, so it remained slow; given the funds, I would have gone with an RB25 and gone wild with it. Now, after life and career and shit, I have money but much less time. Such is life 🤷‍♂️ I'm building an '82 Datsun 280ZX and dropping an RB25 into it, the motor's currently being built. Already have a plan sorted out (most of one anyway) and a whole mess of parts sitting in the garage, waiting to be put to use. Good to be here =D I have a question or two about turbine housings but probably will do a bit more scouring before posting about it....