benl1981

I just ran 18psi and got 247rwkw. I did this mod. Good for piece of mind. If it starts closing when it's on the dyno it would be a hassle.

Yeah I understand about the load. Just looking for comparisons with people who have similar sized turbos

I have a GCG highflow on the rb25. 15psi is up by about 3500-4000rpm in 2nd then less than 3500rpm in 3rd and 4th. In 1st though I think I only have 6psi at ~3900rpm and 11psi ~5000rpm. Is this normal? Anyone with HKS2535 or GCG turbos noticed what there boost is like in 1st. The car is very quick but I reckon the stock turbo is better at <4500rpm in 1st. I think I had 7-8psi by 3500rpm in 1st with the stocker. I guess the load isn't there in 1st so I shouldn't be too tough on it.

247.4rwkw R33GTST Z32 AFM GCG High Flow - R33 exhaust housing (not vg30) 3" Batmbl bellmouth dump --> Catco Cat --> 3.5" Kakimoto with 2 mufflers S15 injectors 450cc Tomei Fuel Pump Turbtech boost valve 18psi - running back to 16psi Stock Airbox 450x300x76 FMIC (Justjap) Full boost actually comes on earlier on the street in 4th than the dyno indicates. 1st and 2nd gear not quite. Tuned at MRC Castle Hill - Mark (Top Bloke and good tuner)

Item:Pipercross High Flow PP1128 Air Filter Age: New Condition: Comes with full bottle of oil Price: $50 (Paid about $80 for it) To Fit: R33GTST, R32GTST - anything that uses an A360 Ryco air filter Location: Sydney - pickup or send (probably about $10 post max)

hahah. No it's just that im soft and prefer to keep my licence. Might be able to get a 3rd gear run sometime.

Yeah I know, but I dont think Ill be able to check even 3rd gear above 5000rpm on the street.

i forgot to ask. When I plug the Hand controller in again (and when it's dry ) Ill do a few 2nd gear to redline pulls and check the peak. He didn't say that they were close to maxing out but I reckon they wouldnt have much left.

I used the below and put in +0.06 as calculated. Also used the 82.5%. Tune done at MRC Castle Hill. Got a nice 247.4rwkw (18psi peak trailing back to 16psi). Tough to test in the wet though. Spins from 4000up. Good tune at a reasonable price. Thanks Birnie and Dale. How do I configure larger injectors? Configuring larger injectors into the PowerFC is quiet simple and takes only a few moments. You need to know the following information before you can continue Current injector size Current injector latency New injector Size New injector Lag time Injector Size and Latency (standard units) Unit Size Latency RB26 444cc/min 0.772msec RB25 370cc/min 0.528msec SR20 (Jap Spec Manual) 448cc/min 0.584msec Nismo 480cc 480cc/min 1.100msec Rx7 550cc 550cc/min 0.730msec Aftermarket New Units 600cc/min 0.810msec To work out new INJECTOR correction and latency; Old SIZE / New Size = Correction New Latency - Old Latency = Latency Correction John plans to install 600cc injectors into his RB26 VL Turbo. The following figure's are used; 444 / 600 = 0.74 * 100 = 74.0% 0.81 - 0.77 = +0.04 msec So he would enter 74% for correction and 0.04 as new latency Once you have switched to larger injectors you should still check your AFR's with a wideband to ensure they are safe and acceptable. For a list of common OEM injectors and their settings try here; Injector Chart - Side Feed OEM Injector Chart - Top Feed OEM

Any upadate on the latency for the S15 injectors? Is -0.06 the setting everyone else is still using? Getting my tune tomorrow.

Chris. It really transforms the car. I didn't enjoy driving it that much with the vg30 housing. Now it is just always there ready to start going. Slightly laggier than stock turbo but not much. Peak Boost probably made 300-500rpm lower but it is the ease with which it builds the boost that is important. You really had to sink your foot into it with the vg30 housing, now you can get 6psi+ without hardly any throttle input. Unless your willing to spend money on cams, or cam gears or 3L etc I wouldn't recommend the vg30 cover. Will be a lot of tuning to get it close to the r33 housing response. My car is 99% street driven so it is important to have the low end. It's never going to be a v8 but anywhere over 3000rpm is great now..

Just swapped back to the smaller cover. Quite a large improvement in boost response. Admittedly the comparison was on the untuned map for both turbos (so the difference may be reduced with a proper tune). Its strange the r34 runs the larger cover. The r34 must spool a little later than the r33 (I guess stock they have the smaller lighter wheels so less noticeable).. Much happier with it now though. I should have probably kept the vg30 cover in case I ever go 3L bottom end though

Looks like an Rb20 turbo..

If you drive around with light throttle you could run 15psi or more and it would still be good on fuel. You need to open the throttle to create boost. So if you drive softly you wont get any benefit from changing the boost setting

What you reckon SK? Did you see my post above? Cheers

So SK. Assuming you had a regular 2.5L normal cams etc would you recommend the vg30 housing in order to get ~ 250rwkw. Should the response still be ok? Putting your invested interest aside hahaha What I'm wondering is if is worth downgrading to the R33 cover to increase response and still have close to 250rwkw. It's about 4-6 hours work taking the turbo off and on again though.

Hahah. SK. I thought you weren't a fan of the vg30 cover? You lost about 250rpm of boost response from some of your old posts... I'm still not sure whether to rip it off. Not the most fun job pulling turbos off. But if you're at about 3000rpm even in 4th and floor it it builds boost quite slowly. I was thinking the r33 cover would make it quite abit more responsive. If the difference isn't huge maybe I won't bother.

I'm surprised the tune can make that much difference... I am thinking of swapping back to a R33 housing. Been doing a bit more reading and it sounds like the larger housing costs about 300rpm of boost response but gives about 15rwkw more.. NYTSKY - I would think if you had 16psi by 3800 in 1st it would be much lower in the higher gears..

Only need the exhaust housing. Will pay $30 or swap for a vg30 one I have (already bored 4 high flow but cracked) cheers

Been bored out to suit gcg highflow. They said they could weld it but I got another one instead. Quite a long crack. Swap for stock r33 exh housing (no cracks). sydney only cheers

NYTSKY - is that 3800rpm/16psi in 2nd gear or in 4th? How does it feel going round corners in 2nd? I find a lot corners that keep the revs below 3000rpm see the engine drop right off boost.

Ok. I got some advice on here and had the GCG highflow done with the larger op6 housing. The response is now pretty average. Considering switching back to an R33 housing. Car is R33 rb25det Mods: 3" and 3.5" turbo back exhaust PFC Z32afm 480cc injectors tomei fuel pump FMIC Boost builds much slower. I am going to modify the actuator a little but it seemed fine when I put it on. GCG had the actuator and set it up. I had another mongrel highflow on before this (slightly smaller wheels and R33 cover and it built boost quite a bit faster) Anway 14psi by about 3700rpm in 4th and 4200rpm in 2nd gear Haven't had a tune so it is running very rich. How much does the tune actually help the boost build (ign timing and correct AFRs)? A few of the tuners say it is mostly the physical size of the turbo. Bit of a pain since I didn't want to pull the turbo off again Its very noticeable coming round a corner in 2nd gear with about 2500-3000rpm - with the stock turbo you squeeze the throttle a bit and the rear wheels would scrabble for traction. Now you can keep your foot planted till you get the boost coming on hard at which point you are back on the straight. Cheers

Boost response.. You can see the boost gauge +7 =about 14psi. Halfway up is 7psi. Stock turbo had 10psi by 3000rpm in 2nd. The 2nd gear test in this isn't really fair since I cracked th throttle at 3000rpm (hence boost comes on later) Definately springs to life a lot slower. Not so good if you want to try and hold the back out a little. Will try the preload bit but I dont think that is the answer. I think the R34 housing and the bigger wheels are maybe a bit too radical for me. Once it gets going it flies though. Hoping a tune could help. MOVIE MOVIE2

So strange - some people with VG30/rb25 highflows say they get 14psi by 3000rpm others more like 3800rpm. I know I get about 7psi by 3000rpm with this turbo - in 2nd gear..

3000rpm. Thats a fair difference. Might try that. Do you usually hear them rattling open though if the tension isn't high enough? When I put the actuator Ion I did have to pull the rod slightly to latch the end on. Maybe needed more? Thanks