Sydneykid

For what its worth, we never run a GTR at over 300 rwkw without an oil cooler. This is especially applicable when the turbos are oil cooled (not water cooled).

OK inasnt I give up, what's high or low mount got to do with it? We run rear/low mount so the weight distribution and the centre of gravity are optimised. Much better than high/front mount. Since it makes no difference as to how much power we make, I am at a loss to understand why we shouldn't run upgraded cams. Help me out here..

That is lower than the standard rev limit. Lowest we ever use is 7500rpm, and standad R32/33 GTR cams are fine at that level

I was sure I answered this a few posts ago ................ Yep, thought I did. Maybe further explanation is required. In the autos on gear changes the ecu retards the ignition, this both smooths out the gearchange and lightens the torque loading on the gearbox. If you put an ignition interceptor (e-manage) between the ecu and the igniters this means that the ignition won't be retarded on gear changes. So you will get flaring and damage to the gearbox over time. In order to work on autos, the e-manage would have to have some extra logic in the software that worked out that a gearchange was happening. Then it would allow the ignition signal from the ecu to pass through without changing it. Since Apexi haven't bothered (and/or been able) to program this logic into Power FC's (no PFC's for autos) I don't see it happening for e-manage any time soon. But maybe I am just being pessimistic. I hope so, ‘cause the Stagea will be here in 2 weeks.

Sounds like compressor surge to me, there are plenty of posts on that subject, I suggest you look it up.

Why would I want one of those? The turbos on the wrong side.

Dyno Dynamics have tried to take out the variation and limit the operator influence with Shoot Out Mode. At the very least it shows the settings on the bottom of the print out for all to see. I have used 4 different dynos (in 2 states) with all now running Shoot Out Mode and the power output (same car in two case) was so close it didn't matter. There a still a few "tricks" that the unscupulous operator can manipulate the power outputs with. But many have woken up to the fact that it isn't really worth the heartache when you can so easily go to another dyno and spend $40 to confirm his readings. :Bang: It's not perfect, but it is way better than it used to be.

Not a bad place to start Roy, if it has too much bite then up the pressure a bit, a couple of psi at a time. You will be amazed at the difference. If it still wheelspins too much go down 2 psi, I personally haven't used less than 15 psi, as I am concerned with spinning the tyre on the rim. Clutch is an issue, as you will have to feed the power not just jump off the side. You have always wanted a twin plate anyway.

See, there is always an exception to every rule. I can give 10 examples of gearboxes in cars (like Buster can) that rip the teeth off 3rd gear with less than 500 rwkw and along comes Leewah to disprove it. I have seen 6 X OS gearboxes lined up in a workshop in Japan, all of them being rebuilt after killing 3rd (and sometimes 4th). I know of a Japanese team that takes a spare gearbox to every drag meet because 9 times out of 10 they have to change it over the weekend. Sometimes they are OK and sometimes not, but I suspect anyone with over 400 rwkw in a GTR is living on borrowed time with a helical cut gearset. Hi Buster, Well I was talking to Rohan from Guru at Philip Island 2 weeks ago, but he isn't really interested in Skylines, Mazdas are his thing. Pfitzner has done a couple of gearboxes for us (not Skylines) and I have talked to him about doing what Leewah did, using a billet sandwich plate. The theory being that the standard one allows the case to distort and lessens the contact area of the gear teeth. For less than $1K it may well be something we try in one of the gearboxes. If it doesn't work I can always use the billet sandwich plate with Pfit's straight cut dog gearset, so it won't be wasted money. I have a little more research to do before I can decide which way to go.

I used an RB26 one, for the same reason as Bl4ck32.

Thanks Mario, I have seen the Power Excel software, but not for long enough to notice any differences other than appearance. Plus the one I have seen was in Japanese, which I don't read very well. Do you have some examples of what is accessible with Excel that isn't with Datalogit?

Nope, Mickey Thompson ET's are a US, crossply, street legal tyre with a tread pattern, not much of a pattern but enough to be classed as a street tyre, DOT approved. Since they are a cross ply, not a radial, the Japanese don't consider them for their street tyre classes. Nitto 555's are a Japanese, radial, street legal tyre with a tread pattern, again not much of a pattern but still street legal, DOT approved. Since they are radial the Japanese (and HPI) do consider then for their street tyre classes. Standard Skyline rims with a pair of such tyres are going to be the best value for ~$700 you will find. To pinch a saying, going to the track with real "street" tyres is like taking a knife to a gunfight. I simply wouldn't bother.

Not that "curious" really, I do consulting enginering from time to time and one of my jobs was to engineer aftermarket suspension for R34 GTT's to suite Australian conditions. The black one was was the first in Sydney that we could get a hold of for any decent period of time , so I did the intial work on it. Then I did futher set up work when they were stuck and couldn't get it to run consistent times. Hence "my suspension set up". I keep saying in numerous posts that there is far more than max engine power involved in running a good time (1/4 or lap). This is just another example.

It works a treat both as a tuner and as a data logger, we have one for the R32 GTR and one for the R32 GTST. The screen layout is pretty much determined by the Apexi machine code in the Power FC. I guess they could have made it prettier, but then they would have had to charge more for it. PS; PM sent

Hi Rick, being a GTST I assume it's 2wd? If so, I think a standard R33 GTST box may well be OK, we have one behind a 420 rwkw RB31DET that is used for circuit racing and the tyres give up long before the gearbox does ie; wheelspin. The problem with the standard gearboxes and OS cross missions is exacerbated by the 4wd and the extra weight of the GTR's. So if you have one, I'd give it a go. That said, there is really no substitute for an auto in a 2wd drag car. Hugo's make a good one with all the gear for around $3K, as used in Sub Zero's Try 09 and others. You just have to learn to live with an auto on the street, personally I can't but many others can. Hope that helps

I think the price is one the web site GM33, if not email them.

Hi Black33, I wrote this for someone else, but I think it answers your question.... The only way to solve voltage max out properly is to fit an AFM with resolution capacity at higher air flows. That means a Z32 or Q45 AFM. For example an Q45 AFM will only show 3 volts at the same airflow as a RB20 AFM will show 5.1 volts (the max). So as soon as you go over 5.1 volts of airflow the ecu doesn't know how much. Remember ~1.1 lb of airflow per minute = 10 bhp. A RB220 AFM will go 5.1 volts at around 40 lbs, so 360 bhp. If you have an engine that makes say 400 bhp, the afm will show 5.1 volts from (40 lbs) 360 bhp to (44 lbs) 400 bhp. So the ecu won't know about the extra 4 lbs of airflow and it won't add fuel for those 4 lbs. This means lean A/F ratios = not so good. A good tuner can get around this by using the rpm and throttle position maps to tell the ecu how much extra fuel to add. This is not perfectly accurate, so you make the A/F ratios a bit rich to be safe. Plus tuning the ignition timing is also pretty tricky, so it tends to be tuned a bit retarded to be safe as well. This looses some power and it takes a lot of programming (mapping time ) to get right. This cost usually exceeds the cost of buying an Z32 or Q45 afm. All a voltage clamp does is stop the ecu seeing voltage over a set amount, usually 5 volts. This stops the ecu from using overboost (really excessive airflow) protection, ie; retard and rich. But it doesn't help the tuning, the effect is still the same as maxing out the afm airflow resolution as per above. Hope that is of some hlep

Yep summoner 50% correct, my suspension set up got the traction and squat so good that a driveshaft became the weakest link. But the fastest run was on Nitto's, not slicks.

Facts Steve, I only deal in facts. And the fact here is the R34 GTT did an 11.6 with 50 bhp less. Whether I wrote the story or someone else did is irrelevant.

Nope it retards the igntion timing and whacks in plenty of extra fuel. "Over boost protection" is what it is know as, but it is really "excessive airflow protection". The ecu makes this decision based on what the AFM is telling it. So boost really has nothing to do with it. The fix is an SAFC, voltage clamp, Boost Cut Defeater or better still replace the std ecu with a Power FC. Yep, full cut is the next step in engine protection programming in the ECU, but you get "retard" and "rich" first. Hope that clarifies

It is over boost protection in the ECU, a boost cut defeater, AFM voltage clamp, SAFC or better still change the ecu to a Power FC will fix it.

Hi GTRboy, I assume by "coil overs " you mean height adjustable. This is good if you want to get the height exactly where you want it, but you can get Bilsteins or Konis with extra circlip grooves for the lower spring seat. This applies to any shock that has separate (not welded on) lower spring seats. It is also good if you want to change the spring rates (a set for road , another set for drag and a set for circuit) as parrallel coils are much cheaper and available off the shelf with a large range of different spring rates. Lastly you can set up the corner weights of the car easier, to balance out the weight distribution. There is no difference in the quality of springs or shocks between none height adjustable and height adjustable. I strongly suggest you read previous threads on European versus Japanese shocks and Australian spring rates before you make a decision on what brand. Hope that helps

Do you "rock it" until the brakes cool?

Shoot that's impressive TT, I have never seen a Skyline rear disc do that. Where they hardened? What pads? Same compound front and rear? Do you have an adj pressure (limiting) valve on the rear? Was it showing signs of excessive rear brake bias?

Swap the springs over, put the higher rated ones in the rear. :headspin: