LeonV

A long screwdriver works really well as a stethoscope, just be sure to press the handle-end against your ear...

I've got one set left, but no more heat shields. I thought I'd sold all my air-boxes but I just found one in my parts storage a few days ago. Actually, when looking at my last set I remembered that I did run them for a short while before converting to triples.

They lost me when they mentioned "Fox-body Mustang" and "very good" without using the word "not" in the same sentence...

I'm with Steve, sounds like a big vac leak to me.

But man, those LS12 guys are taking it to even another level! I want to see that thing run.

I think he's still running it, although it's been a while since he's been on the boards.

Sweet! Reminds me of Bryan Blake's L31 twin-cam.

Sure thing.

I've had similar experiences. However, unlike Carl Beck purports, they do not charge you until the order is shipped.

After break-in, the valves take a while to get out of spec. Nissan's recommended interval (from 240Z FSM) is 10k miles for the first 50k, and every 25-30k miles thereafter. Keep lash the same, otherwise your cylinders will be ingesting different amounts of air/fuel mixture and will be unbalanced. Slightly lower compression has a much lesser effect on power production than choking off a cylinder. If you truly want to know why a cylinder is down on compression, perform a leakdown test and try to listen for pressure escaping from the intake/exhaust/block (breather tube).

Very cool!

Is that you, Jim? Nice!

He was right. There are 2 fuel pump relays in the 260Z. One kills the pump when starting and the other kills the pump below 400RPM. Therefore, the electric fuel pump only runs with the car running.

Interesting. I wonder if it's just the lighting as it looks like they used a flash on the 260Z emblems but not on the 280Z ones. FWIW, I used a flash when I took my pics. Photos can be deceiving...

I'll have to try that! FWIW, the old, broken emblems that I have are definitely more orange than the new emblems on the green car.

Looking at a '76 would be a much better choice.

Excellent!

Nice, cool list!

$150 a set (carbs, manifold, linkage) for 4-screw round tops. Don't know the condition of the throttle shafts though, hence I sell them for ZT's core price. I've got heat shields and air cleaner housings for a little extra. At this point, I don't see myself owning a Z without triples, so I have no need for the SUs.

Jon pretty much said what I was going to say. Higher elevation = less risk of detonation (less cylinder pressure because of thinner atmosphere) and raising compression from 9:1 to 10:1 doesn't do a whole lot in and of itself (~3% gain according to "Internal Combustion Engine Fundamentals", John B. Heywood). As far as lightened flywheels go, we've had this disussion on the board before. The link Jon posted is actually the best I've seen regarding the effects of flywheels (and inertia in general), and is exactly what I was talking about in the prior discussion. A lighter flywheel changes the "effective" mass of the vehicle, and moreso in 1st gear than 5th because of "effective" inertia due to gearing. We (doradox and I) eventually settled the disussion saying that we're both essentially saying the same thing, but in different ways. After a long conversation with an engineering-minded cousin of mine, I gained a deeper understanding of the true differences in views (makes more power vs. removes weight). This all comes down to "free-body diagrams" and Newton's 2nd Law (F=ma). If you isolate the car as whole, lower flywheel inertia is represented as a loss in overall weight. Since motive force stays equal (flywheels don't change engine output), in order for acceleration to increase the mass must proportionally decrease. Since the flywheel rotates, taking 10lb off the flywheel is not the same as 10lb off a non-rotating component, thus the effective weight. Now, if we isolate the drive-wheels in a free-body diagram, we see a different story. The wheels themselves don't change in mass, but acceleration increases. Thus, to the wheels, it looks like more power is being made (more force available to drive the wheels). As you can see, both are valid points of view, if we understand that there are differences in what we're talking about (the whole car vs. just the drive-wheels). Personally, I think it makes more sense to view it form an "effective weight" perspective (the whole car) since that is the actual derived quantity. As you can see in the link, the "effective power" increase is just an approximation of how much weight loss increases acceleration vs. an effectively equal gain in power. It's the same as pulling out the seats of your car and calling it a power gain. It just makes more sense to me, but for those that want to look at isolated drive-wheels, have at it!

The one on the orange car is very faded, so yes, it does look very different. However, I'm sure it started out yellow just like the others.

Overlap isn't the right parameter to talk about. It's the IVC (Intake Valve Closure) point that matters. The later the intake valve closes, the less cylinder pressure you'll have at low RPM. The thing that "hotter" cams do is build cylinder pressure at higher RPM than a stock cam. The reason why a more aggressive cam makes you less prone to detonation is that at high RPM, there is less time for detonation to happen. However, if detonation does happen at high RPM (and high load) then boom goes the dynamite... As for kensval: 10:1 comp, stock cam, and stock EFI DO NOT mix with CA gas. I would bet on you experiencing noticeable pinging if you're currently at MBT timing (not knock-limited). If you don't want to retard timing, there are some stations that still sell 100 AKI ("octane") gas in CA. You can look this up online. Mix the tank 50/50 with 100 and 91 and you get 95 octane. Expect to pay a little extra for 100 octane...

I'm going to try to go through my parts today and see if I can find my 260Z emblems that had some of the resin broken off, in case it may be of interest.

DGV Webers? Well there's your problem! I don't mess with DGVs but I have 2 sets of round-top SUs and will be taking them to the Datsun swap meet in Manteca on Saturday.

Adjust your valves ASAP. Lash gets tighter over time because the valves wear into their seats. You should see a bump in compression across the board, as well as better idle and low RPM running. Tight valves will "burn" (erode).