Sydneykid

The 2.6 klitre made 618 bhp on the engine dyno with Group A turbos:cheers:

Hi Mark, it's actually quite common. The idea is to avoid reversion form a big turbo gpoing back though through the AFM when it is mounted in front of the turbo. By having it after the intercooler there is no reversion problems.

Drove the Stagea around a bit today, not very far but enough to notice some things. Most obvious is the launch, with the standard intercooler it used to get 0.5 bar held against the torque converter at 2,300 rpm. With the R34GTT intercooler it gets to 0.7 bar at 2,400 rpm, boy does it jump off the line now, whiplash. Also it used to noticeably taper off over 5,000 rpm in power, it doesn't now, it pulls to 6,500 rpm much freer. Can't wait to get the exhaust on it and whack it on the dyno:cheers:

Exactly:cheers:

Hi Stephen, nope the HICAS is not your friend even when the car was new.

It is printed on the body of the AFM near the socket:cheers:

Single Q45 is easiest and will handle all the power a GT30 can muster:cheers:

The under bonnet temp of an RB in a S13/14/15 is always an issue. What sort of air filter, heat shielding and ambient airflow inlet are you using? For the same reason I would always suggest an oil cooler.

The Skyline is saw the boost through Q45 on, had ~85 mm ID pipe to match the AFM ID (from the intercooler to the plenum). I have never tried it myself, so I have no idea what issues they had getting it to work. I also don't know what boost they were running, it had a big ass HKS turbo on it, so it had plenty of airflow.

OK the R34GTT intercooler is in. The latest pictures are in the opening post, which is updated. I haven't driven it yet, I'll do that early in the morning. I hope to fit the exhaust next week and then stick it on the dyno.

Bl4cK32 answered most of this. I will add that I have seen a car in Japan with a Q45 AFM plumbed into the pipework from the intercooler to the plenum. Certainly no problem maxing out a set of 444 cc injectors. My own RB31DET maxes out 565 cc injectors with a single Q45 AFM, and it is placed before the turbo (ie; in the usual location). Sorry we only work on team race cars, there is simply not enough time to do retail work during racing season. Plus you wouldn't want me to tune your car, I am far from the best tuner. Shoot I don't even do the race cars, our team tuner won't let me near them. But he is a genius after all.

Hi Mark, there are whole pile of issues here and they are heavily interrelated. We are only interested in circuit racing. So drag power levels are not something we have spent a lot of time testing components for. Certainly not to the same thorough levels we do for maximising our circuit speed and reliability. Everything is pretty mucgh engine dyno, chassis dyno and flow bench tested before it is signed off to go racing. Once you get over ~650 bhp the standard plenum has distribution issues. So it is best to change it, whether going single throttle butterfly or multiples. The best plenum I have seen in action with the multiple throttle butterfly (standard size) is the Nismo plenum. That combo seems to work very well and ~750 bhp is OK. Maybe more, but I haven't seen it. From what I have seen, the faster circuit cars at Tsukuba use the Nismo plenum. Over ~750 bhp, upgrading the throttle bodies is not worth it as the turbo/turbos required to make that sort of power are simply not responsive. GTR's making that sort of power are pretty useless for anything other than drag racing and so throttle response is irrelevant anyway. Once you get to that point, there are number of plenums with single throttle bodies. I prefer the Jun plenum, but the Veilside achieves good results as well. When you get to that stage, plenum cost is pretty much irrlelevant, as you will have spent over $200K on the rest of the car to support and use that sort of power output.

Standard R34 GTT rims fit on Stageas, no problems:cheers:

It's a large expense for testing, expecially testing that has already been done by many people. RB powered GTR's have been arround for 16 years, circuit racing drag racing and road cars, there is very little that hasn't been well and truly tested in that time. My suggestion, as always, is to spend the money on something that actually makes the car faster.

The standard PFC uses AFM, Djetro versions can use MAP. As for needing MAP for "really big power", I have seen an RB make 1100 bhp using AFM's, is that "really big" enough "power" for you? The NA injectors are 270 cc's (from memory) so you can adjust the PFC master fuel correction to -20%, that will get it running. You should tune the maps though for long term use. But 270 bhp is not much for an RB30/25, so I suspect it is only a tempory situation. You can get Datalogit for lap top tuning, although the Commander does a pretty good job. www.fc-datalogit.com

Yep prices vary a lot, are you using the sulphur added formula?

Then you should go single throttle body, you won't notice any loss of throttle response at that power level. The turbo/tubos will be so big that they will have more lag than using a single throttle body will introduce:cheers:

Thanks Adrian, what's a 10lb refill cost?

Inside tyre wear is an indication of either too much toe out or too much negative camber. Post up the wheel alignment readings for your "regular 4 wheel alignments" and we will be able to diagnose the problem. Toe adjustment is available using the standard components. Camber adjustment will require a kit, around $100 for most Skylines from Whiteline. I suggest that Whiteline springs will improve the ride problem (second choice would be Kings). Cheaper than 1 pair of tyres including fitting. You haven't specified the shock absorber brand, are they standard? If the car has travelled more than 60,000 k's then the shocks should be replaced. I would suggest a set of Bilsteins, add extra circlip grooves if you want to set the height exactly to your liking. Usually if the front suspension is too low or poorly aligned, the rear is worse. Once again toe adjustment is available using the standard components. Small camber adjustments are also available using the standard adjusters. Larger camber adjustment will require a kit, around $100 for most Skylines from Whiteline. Hope that is of some help.

Put a 4" cat on and compare to a 3" straight through pipe and you won't see any difference. I have and it's true, other people have and found the same thing, Zoom did it and agreed and printed the results. In my opinion the loss of power excuse is out of date. You used to be able to rely on LPG for 100 RON, but since they started to make it to a price, not a standard, I personally can't depend on it any more. I have a friend with a Cobra replcia that runs on gas and he is having more and more problems with pinging. Very few people buy LPG for its RON, they buy it for it's price.