TimZ

Joe... The method that Rick suggested is what I was going to suggest, too. Try running around 10 degrees or so at idle, then just ramp back it in once you are off idle. It is a good idea to "isolate" the idle timing by a cell on each side, just to keep the timing from moving around at idle. Another thing you might try is setting the bottom breakpoints above idle and just using the initial timing setting. I'm pretty sure the interpolation doesn't start until you are on the map. The popping on decel is usual due to some sort of rich-to-lean transition. Usually you are a bit rich on WOT and you end up putting unburned fuel into the exhaust. The fact that you were rich says that there was no oxygen left for that fuel to burn. Then when you drop throttle, the mixture goes lean, which basically introduces a bunch of hot oxygen into the exhaust and that ignites the fuel that was sitting there. So, this can happen for several reasons. If your Min injector on-time is too low, then it's possible that the system is commanding a PW that's just too small for the injector to open. The decel fuel cut will also do this, if you have it enabled. It's also possible that the fuel map could just be set too lean at those points.

Thanks, Jon. I noticed that answer in one of the replies, and that is pretty much what I wanted to know. It just seems like asking anything about this part aside from "where can I get one" is somehow taboo, and that does not set well with me. As i said, I AM considering buying one, and just wanted to know what, if any, "gotchas" might be associated with it. Wouldn't be even close to the first time.

Thanks for the browbeating, guys - much appreciated. Am I now to be considered a "naysayer" or "nonbeliever" because I asked a simple question? Never mind.

Yep - it's possible. It's also possible that I have been burned in the past by other aftermarket pieces that made formerly simple service procedures into difficult ones. I'm thinking about purchasing one of these, and I'd like to have a feel for what I'm really signing up for. The performance to pain ratio is important to me. It sounds like my old chain blocking tool might still work, or I might have to make another one that fits the new profile.

Blackstar - I want some of that, just because it sounds ominous...

The wedge also serves to keep the chain from falling off of the crank sprocket, so I don't have to worry about whether my cam timing is a tooth off. This was more what I was thinking of -I already have the tensioner retainer thingy that keeps the tensioner "foot" from falling out. So it sounds like the answer is that I will have to come up with something else if I don't like pulling the front cover to confirm chain alignment?

Okay, so here's a new question - will my old chain blocking tool still work with this piece, or am I going to have to make a new one?

Cobra Racing Seat - Bolt in for 280Z Boyd's Billets 16x8 wheels with Kumho V700 Victoracers 245/45ZR16

Nope. One caveat - If anything else is using the thermo switch, then it will also be activated by the manual switch.

That is helpful - thanks! Finally, a compelling reason to use STP...

You made me spit out my beer - damn!

1.324" - All the specs are in the eBay ad.

Just added these: Z31 5 lug hub conversion Swain Coated Arias Forged Pistons - 87mm ...And still have these for sale: Polished Upper Thermostat Housing - L-series 14" Electric Puller Fan EDIT: Someone kindly pointed out that I forgot to update the link to the relisted items - it's fixed now. DOH

Sorry - it was the only thing I had quick access to that showed the timing curve with respect to rpm and map

After the torque peak, it's usually okay to ramp timing back in up to redline, something like this: Start off by ramping in a small amount, say increase a total of 2 or 3 degrees linearly from torque peak to redline. Also, you never mentioned what CR you are running (or at least I don't recall). I'm running 7.5:1 and still have more than 25degrees at 26 psi, once the revs get above 5500. My engine is probably a bit of a "special case", but you might be able to live with more timing. Cautiously, of course.

Maybe you could dial in a bit more timing - what does your timing curve look like? I'm assuming you have a programmable?

Sorry - I wasn't either - I just couldn't resist. Congrats on the great results with your head!

johnc already did your homework for you... Also, just to be anal, the bolts are only loaded in shear if they are loose. When properly tightened, the friction joint should take the shear load, and the bolts are only stressed in tension. You do want to protect for the case where the bolts are loose, or if a shock load overcomes the clamping force friction, so the 12.9 bolts are still a good idea.

Maybe a little late, but have you tried re-torquing the head? If this just started after 10K miles, it probably won't help, but it wouldn't hurt anything, either. As far as de-torquing the head, I don't think that it's necessary to de-torque in sequence, so long as the head is stone cold (as in sat at least overnight). That said, it certainly wouldn't hurt anything to go in sequence, so why not? And, regarding weeping right after assembly, I have found that re-torquing after two or three heat cycles can eliminate any initial weeping problems. Seems like every time I mention this, somebody chimes in and says that that's not necessary, but I have had good results with this method. Again, you should never re-torque a head that is not stone cold.

That's correct.

The pump showed up today and it is the correct part, just like in John's pics. The impeller is noticeably bigger than the normal stock pump - it's fully 0.200" larger in diameter. So kudos to Courtesy Nissan (as usual).

I believe that it was a local place that my machinist uses - I'll have to check to see who it was. In the past, my experience had also been that EGTs would drop with added timing. In this case it did not seem to help.

If its made from aluminum, then it has to be two piece - aluminum wouldn't last very long as the friction surface.

What turbo are you running? Since changing to the GT42R, my EGTs seem to have gone up considerably - I'm now seeing temps on the order of 1800-1850 degF. With my old T64 o-trim turbo my EGTs were much cooler - more like 1500 degF. Since the turbo and exhaust were the only real difference between the two cases, it appears that the lower exhaust backpressure has something to do with it. It's possible that the decreased exhaust manifold pressure (it's now lower than the intake manifold pressure) is allowing some amount of "blow-through" during the overlap period, and perhaps this mixture is getting burned in the exhaust. As John mentioned, I was not able to get the temps down appreciably with timing or fuel (although the temps do go higher if I try to run much leaner than 11.5:1) This was pretty alarming to me at first, but the more people I talk to about this, the more it seems that this is common for very high output turbo engines. I recently dropped a valve seat, which was most likely directly attributable to the higher temps. I am currently replacing the valves and valve seats with pieces made with the higher temperatures in mind. I'll post more details on this a I work them out. Incidentally, my combustion chambers and pistons had been ceramic coated, and they both looked fine, aside from the damage done by the valve seat on #5. The ceramic coating had not flaked off, and appeared to be doing its job. The surfaces of both the pistons and the combustion chambers were smooth and not pitted at all.

Not the answer to the question you asked (Paul and others handled that pretty well already), but did you mean to say you are using SS braided hose as replacements for the upper and lower rad hoses? This is fine so long as your engine is solid mounted, but will fatigue your rad inlet and outlets if the engine can move with respect to the frame.