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Hi Bigcarl, we have 1 on an R32GTST with an RB20DET that makes 210 rwkw and 1 on an R34GTT with an RB25DET that makes 240 rwkw, both at 1.3 bar and on Optimax. If I stick some ELF LMS in the R34 I could easily make 270 rwkw at 1.4 bar which is the theoretical turbo limit of 450 bhp.

The RB20 is internally untouched with GTR pump, slit dump, 3" exhaust, HKS POD, shield and air feed and Power FC and has 170,000 k's on it. The RB25, with 60,000 k's has lots more mods, Tomei cams, porting, split dump, 3.5" exhaust, Power FC, Z32 AFM, injectors, Bosch fuel pump, HKS pod with shield and air feed.

This is similiar to the results Ben achieved with the HPI R34 which made 231 rwkw at 1.1 bar. His didn't have the split dump, a 3" exhaust and the head wasn't ported, but it had a thick head gasket (I don't like them). I have the Croydon dyno sheet somewhere around if you want it.

Gotta ask, why do you want to know?

because im running one , just got a split dump pipe fom ces racing in queensland and a 3inch cat. i was running stock cat and dump with 3inch exhaust and pulled 204rwkws at 1.2bar, getting retune soon and just wanted an idea of what to expect! 230to 240rwkws sounds pretty good , cant wait to feel the difference!

It's funny... when I email well "known" turbo shops and ask then what turbo would be suitable for 250rwkw on an RB25DET they all say GT30 but everyone on here says get the GCG 450hp setup.

GCG 450hp = ~$2,200

GT30 Setup = ~$3,625

I wonder why that is....

(Edit: Price)

double posting eh? like what? :P you need a proper dump pipe which is recommended for decent flow anyhow.. an external wastegate (~$600), and i think the GT30 may require a bit of a spacer to get it at the right level over the manifold ($30), then your water and oil lines, which you probably need to upgrade on a highflow anywayz ($200). You're up for $3k instead of $2.2k - woopdi....

Hi benm, I have never had to change anything when I have had a ball bearing hi flow done by GCG. All the oil lines, water lines, inlet pipes, outlet pipes and even the std dump, fit straight back on. As does the std heat shield, which I have found helps the under bonnet temperatures a lot.

You only have to change what you want to for improved performance. Most people do the split dump pipe upgrade at the same time, but you don't HAVE TO. You can do it later if there are budget constraints. If you are aiming for over 220 rwkw I would suggest that the only other upgrade you would need would be replacing the rubber air inlet hose from the AFM to the turbo. They have habit of sucking closed when they get old.

Hope that helps some more

Sydneykid, what do you recommend replacing the intake piping with? I got quoted around $400 to do the whole lot from intake through turbo up to the intercooler, but with what exactly I wasn't told. At present only a bit of the intake side of the intercooler is done in the nice shiny stuff. At present it looks ugly and quite restrictive, with press bends in the metal bits and rubber/plastic elsewhere.

ht%20clamps.jpgaluminium%20donut%202%201-2%20inch.jpgpipes.jpgSFS%20Straights.jpg

Hi JimX, I use aluminium pipe work that I cut up myself. I buy the straight bits from Capral and the bends from GCG. If I want a tight bend I use donuts and cut them at the angle I need. The local welding shop welds up the joins for me and I use the die grinder to tidy up the inside of the pipe. They are pretty good welders, so there is not much dag in there. I use straight silicone hose, cut to length, to join it up, and stainless steel clamps (both from GCG).

Hope that helps

Probly to Sydney Kid,

how much to hi-flow your stock t28 from CGC anyway?

Also on a standard internal RB25DET, front mount, zorst all the way, chipped ECU ( more rich and no Rev, speed limiter ) would i be able to expect running it on 12psi and make around 210kw@wheel or this is a dreaming figure?

Hi West, suggestions follow your questions......

"how much to hi-flow your stock t28 from CGC anyway?"

I suggest you give them a call and ask.

"Also on a standard internal RB25DET, front mount, zorst all the way, chipped ECU ( more rich and no Rev, speed limiter ) would i be able to expect running it on 12psi and make around 210kw@wheel or this is a dreaming figure?"

I have seen 205 rwkw on an R33 GTST with FMIC, POD, shield, CAI, turbo back exhaust with a split dump and a hi flow cat, on the std turbo at 13 psi using a Power FC. So if your ECU chip is well tuned, then 210 rwkw is within reach. Turbo didn't last long though, spat a ceramic turbine wheel off after 5 laps on the circuit. We put a GCG ball bearing hi flow on it and it went to 225 rwkw at the same boost.

Too many people underestimate how important the tuning really is, they think you can just bolt on the good parts and it will make the power. With all the above stuff on the car and poor tuning, it wouldn't have made 180 rwkw.

Hope that helps

Thanks SydneyKid,

when i said 210@wheel, i meant the CGC was included. So is 225kw is the max for stock standard RB25DET also for the injectors?

Another question was would RX7 injectors fit straight into Gtst? Have you ever tune a skyline with an ECU got chip in Japan? ( chipped in JP mean not tuneable in Aus )

Thanks

Thanks SydneyKid,

when i said 210@wheel, i meant the CGC was included.Thanks

If I got this with a hiflowed r33 turbo i'd be -very- disappointed. As far as im concerned $2,000 for a hiflowed turbo would want to get me more than 10-20rwkw.

Hi benm, the best we got out of the standard turbo was 205 rwkw and then it shat itself. The best we got of of the ball bearing hi flow on that same car was 270 rwkw using Elf LMS. So that's 65 rwkw in max power terms, but it was closer to a 90 rwkw increase in average power over the rpm range we use.

Hi West, as for injectors, we can generally get to 250 rwkw on the standard R33 GTST injectors, with a slight (less than 10%) increase in fuel pressure. R32 GTST injectors seem to run out of capacity around 210 rwkw. We use Series V RX7 Turbo Injectors (550 cc's) in R32's as they are high impedance and top feed, same as the std injectors. R33 GTST's are low impedance and side feed, so injectors are hard to find. R34 GTT's are even tougher as they have a small diameter, plastic, Bosch injector, and there aren't many choices for upgrading those.

Hope that helps

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