Moodles2

From memory, even %1 rolling diameter difference is enough to cause ATTESSA to put a small ammount of power to the front wheels full time, this will cook the clutch packs in the transfer case in time. Even having the exact same rims front and back, with the exact same tyres but only tread depeth difference is still enough to make the ATTESSA think there is fulltime wheel spin.

If you do have a stock ECU, you could try disconnecting the battery and pumping the brake pedal to get all the charge out the system so the ECU has to re-learn timing etc. If you have a aftermarket ECU like a PowerFC this won't do anything. If you are running a Z32 AFM on a untuned stock ECU, your spark plugs will be completely black from overfueling (once they're fouled to hell it's difficult to start an engine on them), pull one plug out or all them out and take a look.

Check kudosmotorsports on here, was clearing out alot of Nismo gear for cheap, amongst the gear were coppermix kits

Sell the rims, or sell the GTR. You shouldn't run staggered rims, let alone different tyre profiles... unless you want to convert your GTR to permanent RWD by destroying the transfer case.

Would something like this be useful to the existing sandwich plate? http://justjap.com/store/product.php?productid=20104&cat=&page=1

Exhaust gasket or turbo gasket probably, by broken studs

I might be worried with shuffling (or whatever that term is when the compressor stalls due to the engine being unable to ingest that air at low or no throttle), that is if the HKS hardpipe kit replaces the factory intake piping ("twin turbo" pipe, accordion pipes etc) or is this only a problem with -10's? The HKS dumps (60mm out) and Apexi front pipe (2x60mm in, 80mm out) might be a restriction at 400-450. Also ceramic coating the stock manifolds is actually inexpensive, had them both done as a pair for approx $175 inside and out.

Driving course.

Well then with that Z32 ECU, you better not be running it on a stock ECU.

Car will still idle with a boost leak, it will hunt badly while idling. It should start and idle though with the AFM disconnected (limp home mode). It's likely the solder joints need re-doing on the AFM, or the AFM plug needs to be fixed/replaced. Are you sure you didn't leave a rag or something in the piping? Why did you remove the AFM anyway?

I thought it was a RB26DE (or a RB20DE)

Wedge is correct, I have a R34 stock gtr front pipe lying around

Best to confirm these changes on the dyno, as you can make things worse (with good intentions)

http://www.kudosmotorsports.com/catalog/ngk-ntk-lambda-sensor-oxygen-ntk-nissan-skyline-r32-gts-gts4-gtst-gts25-r33-gts25-gts4-gts25t-p-1023.html $77

White connector (about 12 pins) is the CONSULT/OBDII port.

You probably wouldn't have a LSD anymore.

I tend to pour as much oil into the oil cooler lines via the filter relocator as I can (with the filter off), put 4.5L in via oil cap. Disconnect CAS, crank it for abit and then start it with the CAS connected again. Let it idle for a minute, check oil levels with engine off and keep adding until it hits the hump on the dipstick.

Google "magnatec sludge" for more info.

GTR rear diffs are mechanical LSDs (hypoid-type). V-Spec rear diffs are active LSDs (unsure on type). After looking into EPX, it's only suitable for regular diffs (single spinners), you can put it in the front diff as it's a regular diff.

Possibly the CAS wasn't put back on perfectly.

Now you mention the fuel economy, the oxygen sensor probably needs changing. Without a working oxygen sensor the ECU will keep the mixture rich so that would explain the black plugs (plus they look really old)

Nissan service manual specifies 80w90 (or 85w90 I can't remember). 85w140 is fine though but more ideal for a track driven car. The thicker the hot rating (140 in 85w140), the different the LSD will behave as it will tend to lock up more in slow speed stuff, like parking or going around roundabouts (though these 2 examples are the extremes of shockproof lightweight, so no guarantee it will happen with that the fluid you've selected).

The stock cluster isn't in PSI, it's in mmHg. +7 mmHg is approx 13.2psi.

2 options, Tomei make a special sealent for the ITB's or XS Engineering (may be discontiuned but i still see them on ebay) make rubber? throttle body shaft seals

TPS should be between 0.4v and 0.5v (0.44v ideally) on ignition and idle. TPS on WOT I can't remember, about 4.5v. Z32 I can't comment on ignition or idle since I don't have one (stock RB26 65mm AFM ignition on is 0.3v-0.4v and 1v idle), although at WOT (with revs close to redline) with 500hp (limit of the Z32) will be about 5v.