Sydneykid

There are 2 issues with AFM's, one is the restriction caused by the small diameter. The second problem is the one you hear about most often and that is the calibration of the hot wire sensor for higher airflows. The Nismo GTR replacement AFM's I have seen are the standard GTR diameter (65 mm) with what look like Z32 sensors inserted into them (replacing the standard sensor). This fixes the calibration problem, but does nothing for the diameter based restriction.

Yep, the red motor is bit shorter than an RB, the bell housing is a fair bit bigger as well. I drove an EH with an RB30ET in it a few years back. Went real well:cheers:

Mine cost ~$400 from Nengun:cheers:

HKS seem to rate their tubos about 10% conservative. So 330 PS = 245 kw - 50 kw for transmission losses = 195 rwkw. Looks like HKS and I agree. Pretty irrelevant in this instance, a it simply runs out of airflow. So no matter how much you improve the efficiency, it has no more flow to give. Reducing the restrictions would (as always) result in lower boost levels, but they have no effect on the maximium airflow.

It is not often that we get a decent suspension thread going on SAU, so please post up what results you get.

Mid 60's, mmmmmm EH perhaps? I would run a 120 degree bend at the throttle body, that will avoid the cross over pipe behind the radiator. This one has the intercooler pipework running outboard of the top radiator hose. It is more common to run the intercooler pipework inboard of the top radiator hose as it lessens the sharpness of the bend at the RHS subframe. Hope that is of some help.

Hi Steven, no it won't work, not even close. Nissan automatic ECU's have shift logic (eg; they cut ignition on gearchanges to smooth them out and help the gearbox to last longer). This extensive amount of logic is not programmed into Power FC's, I guess Apexi figured they would have to charge too much or they don't want to get into auto gearbox programming.

They work very well, we have 2 on GTR's and 1 on a GTST. But there is no bling appeal, no blue screen, you just have the Commander.

Boost is irrelevant, it is excessive airflow that can not be metered by the AFM that causes problems. You might get to 33 lbs of airflow per minute (~215 rwkw) before it becomes an issue. But it really depends on how much the tuning is compromised by the lack of ignition timing adjustability.

Camber is not your problem, 5 degrees negative is rediculous on its own. Then add that to 9 degrees postive caster and you have ~14 degrees on a 20 degree steering corner. That's a lot of roll to be compensating for, it must fee like its falling over the outside front. What spring and anti roll rates are you using? How much compression damping is there in the shocks? That's what I would be looking for, not more camber.

Sorry, I left out tyre pressure, to make that post complete I have added it, so please have a reread above.

There is another thread going on front camber settings. So pop over and have a read of it as well. Let me start off this one with my methodology. The job of a spring is to hold the car up and allow sufficient compliance for riding the bumps. I like to run as soft a spring rate as I can, this means the tyres are in contact with the road as much as possible. As the spring rate goes up the tyres tend to skip over the small bumps and ridges, this reduces traction. The main job of the shocks is to control the springs, prevent them oscillating after they have been compressed by a bump. Shocks also have to control the stabiliser bars, they are a spring as well. With the sophisticated valving available these days we can also use the shocks to control the chassis movement, lessen the roll squat and dive. This means we can use even softer springs to ride the bumps and hop the ripple strips, which on many circuits is essential for good lap times. I use stabiliser bars to control the roll, adjustable to alter the balance. They are simply the most effective method, that's why circuit race cars (all the way to F1) have ****pit adjustable bars. The front suspension geometry is set up for anti dive under brakes, this limits the weight transfer so the rear brakes can help the front brakes. The rear suspension geometry is set up for a little anti squat, otherwise you get excessive front end lift under power on corner exits (understeer). The wheel alignment settings are based on maximising the tyre contact patch, the more of the tyre on the road, the more traction. I set that up using a tyre pyrometer, with the aim of equalising the tyre temperatures across the tread. Tyre pressure also have a role to play in this, if the tyre pressure is too low the centre of the tread will not have the same temperature as the outsides. This is because it will not have as much contract with the road. Vice versa for too high a pressure. The Japanese have a tendency to try and do all of the above with the spring, so they end up with ridiculously high spring rates. They do not have our European based culture of using stabiliser bars, they didn't have a KMac or a Selbys. Plus Japanese circuits are very flat, not at all bumpy like we have here. It is also worth remembering that good Japanese mechanics charge like brain surgeons, so a bolt on solution is much cheaper to install. Keeping that in mind, let's get specific with a GTST. The rear spring rate needs to be low enough to provide a bit of squat under acceleration, weight transfer to the rear helps the traction. Around 200 lbs is not a bad place to start, hardly ever going over 250 lbs. The front spring rate is determined by "what the tyre likes", some tyres (slicks) need a high spring rate, others (road tyres) need a low spring rate, the "R" compound tyres need something in between. Around 350 lbs is not a bad place to start for a front spring rate. Front stabiliser bar on front engine, rear wheel drive car is of necessity pretty big. I use a 27 mm adjustable on GTST's. The rear anti roll is tricky, too high a rate and power oversteer becomes an issue. I use a 22 mm adjustable in the wet or on slippery circuits, 24 mm adjustable in the dry on grippy circuits. Sub frame bushes on the rear are essential for a limited amount of squat, and the HICAS is not your friend, remove it. I run a small amount of toe in on the rear, 1 or 2 mm each side. Camber is not excessive other wise you loose traction under acceleration, between 1 and 2 degrees negative usually gives the best tyre temperatures. As much caster on the front as you can get, usually 6 to 7 degrees before the tyres start hitting the front of the guards. Front camber, is again determined by the tyre temperatures. I have yet to find a circuit anywhere in Australia where I need to run more than 4 degrees. If I ever do, it will be because the spring, anti roll and shock rates are too low. So I will go up in spring rate or bar size and adjust the shocks rather than use more camber, the car will be faster that way. That's about it for me, it's racing season and we have 3 meetings in 2 states in 4 weeks, so work beckons. Hope it was of some help. PS; Tyre pressures are totally dependant on the tyres you use, different brands, different sizes and different compounds require different pressures. For Yokohama 032R’s (the Improved Production Control Tyre) and 048R’s (the Production Car Control Tyre) a hot pressure in the mid 30’s (34 to 36) is what the manufacturer recommends. I would start their and see what the tyre temperatures tell you.

A little explanation first, caster occurs when you turn the steering wheel. The outside wheel goes negative camber, the more you turn the wheel the move camber change you get. Think of it as camber on demand. when the corner is tighter, you turn the steering wheel more, so you get more negative camber on the outside wheel. This increases the contact patch of the tyres because the chassis leans over (call it body roll if you must). The real bonus with caster is not only does the oustide wheel go negative camber in respone to steering wheel inputs, the inside wheel equally goes positive camber. So when the chassis leans away form the inside wheel, it helps to have less negative camber on that front wheel (increasing the tyre contact patch there as well). So by having more caster you have to run less camber. This is good because when you want to stop, more of the tyre is on the road. When you have lots of negative camber you are only using the inside of the tyre to stop. Also when you brake heavily, the weight transfers to the front, compresses the front springs and this bring on even more negative camber. My routine for changing over a road car to a track car, is to jack it up to change the tyres ("R" compound at the very least). While it is up in the air, I adjust the stabiliser bars and I can simply wind on a bit more camber if I need to. I have a portable camber gauge for that purpose. You could simply mark the rotating adjuster in increments of 1 degree when it is on the wheel aligner, then you don't need to carry a camber gauge. Let's face it, jacking the car up is the hard part, a minute or two extra spent adjusting is insignificant. I have been known to change the tyres and do the adjustments at the track, sometimes though, I do it the night before and drive to the track ready to go. Then change it back to the road settings when I get home, in the comfort of my own garage. Hi jason, I think perhaps you have caster and camber mixed up. East Coast are far to experienced to send a car out with 6 degrees negative camber on the front. Either that or you don't have enough anti roll, insufficient anti dive, far too soft a spring rate and shock valving in compression. That much camber is simply not necessary when the car is set up correctly. Hope that helps:cheers:

I measured a tree doing 45kph with a Police Radar once, no it wasn't turbo'd. :wassup:

We have had 2 X 2510 's on a GTR. It is quite a small turbo, so a single one would have not much airflow capacity over 200 rwkw I would think..

Why don't you use the standard one?

Yes:cheers:

And the result was?

Recommendation #1= Sell Mines ECU and SAFC and buy Power FC, Z32 AFM, fuel pump and injectors. Why = because the 2540 will exceed the standard fuel supply capability. Plus exceeed the SAFC's ability to balance the A/F ratios and the ignition timing. Recommendation #2 = Buy a Nismo adg fuel pressure regulator, and a GTR fuel pump and use the Mines ECU and the SAFC to get a pretty close tune. Depending on the quality of the tune, you may not be able to use the full capability of the 2540 ie run lower boost. It's a compromise, but cheap. Hope that is of some help:cheers:

That explains the high reading. :wassup:

You like Reedy's results, he has a Power FC and a Z32 AFM.

Sorry not enough information to give a good answer. Is the standard harness cut? Is the standard ECU plug still there? Does it have a wally adaptor that goes from the standard plug to the EMS plug? Have you tried plugging in a standard ECU?

Yep it will work, but if you have enough power to really need a Z32 afm I wouldn't be tuning my car with an SAFC. Too many compromises:cheers:

Maybe the tyres were bald:cheers:

That's ID, they are 80 mm OD. It is Nissan's convention to measure AFM's by their OD.