Jeff G 78

I never understood the '75-only pinion pattern either. They did a few odd things over the years.

I'm confused by what you are saying. Yes, Nissan used HLS30 for the US 240Z and 280Z, but they used RLS30 for the 260Z.

Either the calculations were way off or the materials/manufacturing didn't match the engineer's design. Either way, this should never happen. I can't imagine that there wasn't a huge factor of safety built in to the design as well.

No, it is a 2 seater. I thought maybe the late 74 2+2 got the R200, but it doesn't show up in the FSM until '75. Of course, we all know that there were mid-year changes throughout the S30 run. I would think that something as significant as a differential would have shown up in the FSM since the dealers would have to service them.

My late '74 coupe manual had a R180 and my manual '75 coupe had a R200. My understanding was always that the R200 was introduced with the '75 manual. I just looked at the '74 FSM and it only shows a 3.36 R180 for the auto and a 3.54 R180 for the manual. The '75 FSM only lists a R200 3.54 ratio. Has anybody looked at the microfiche to see if a R200 is listed for the 2+2 260Z?

When I was in college, We had to do a semester-long design project for a bomb retrieval robot and detonation chamber combo machine. It would be interesting to see how their chamber was designed and what failed and then compare the specs to what I designed 30+ years ago. Of course in the late 80's, we had no CAD or CAE. It was all hand calculations and paper drafting.

I'm not a fan of convertible S30's, but this is as nice as any I've seen. The trans sounded super lazy in the video. Other than that, it appears to be a really nice Z.

We got rain too in AZ for the first time in months. This week is downright chilly at only 95 - 100F compared to last week.

I went from MI to AZ, so I think I'm just as far away from you as I was before. Same goes to you Cliff. If you ever make it to the desert, let me know.

Chucking a rocker refers to a rocker coming dislodged from it's position. This can happen due to it being adjusted too loose, over-rev, or weak springs. If it partially dislodged, it could have caught the edge of the lobe. In your case, the rocker could have pivoted rearward. By the time the cam rotated back around, it was BARELY over the lobe. With the rocker pivoted, I'll bet that the chip in the rocker lines up with the chip in the lobe. The other possibility for the lobe damage is that it's in the rear of the lobe which could get damaged during assembly in the head. The cam is slid through the towers and if it wasn't carefully lined up, I suppose it could have caught a tower just right to chip it. As for the rocker, I'd sure verify that the pad isn't split. If it sheers, it will destroy the cam and then send metal throughout the engine.

What if it chucked a rocker? The chip on the rocker and the chip on the lobe could have been done together? I've chucked rockers on the track with no damage, but I guess it could happen.

Those sure don't look new to me. I could be wrong, but they look like they have old oil residue on them. What do the lash pad ends look like? As for the S side, I can't tell what's going on there. I have never seen a pad split, so I assumed it was just a debris line. I thought you were referring to the chip in the edge which I've also never seen. I'd probably have a machine shop magnaflux that and see if it's really a crack. You might even be able to tap on a good rocker and then tap on that and listen for a different tone. It should thud if it's cracked. Was the shop that did this work reputable? I would not be comfortable with what I'm seeing.

Were the rockers resurfaced because they don't look new. That little spot doesn't scare me as much as the one on the lobe, though if they were not resurfaced, they shouldn't be paired with a new cam.

I just looked at the pics of my internally oiled cam and the oil hole is opposite the lobe peak on the base circle. Zed Head thought that the chip was on the base circle, but I don't think that's the case. If true, there would be an oil hole visible. I believe the chip is at the peak of the lobe and it's just hard to see due to the camera angle. If that's the case, the chip is on the peak of the lobe, not the base circle, though the majority of the chip as on the downslope. Still, the loads will be high in that section of the lobe.

You are right! I wasn't even looking for the oil holes. That's an externally oiled cam and I can't tell if it's new, but there is a wipe pattern that wouldn't be there if it was brand new.

I'd be a bit worried about that chip as it's a few mm into the wipe pattern. Make sure there are no protrusions around the edges that could eat the rocker. I'd also be a bit worried that it could propagate across the lobe.

I found it. It was on FB. The tank is for a 35 Plymouth.

The plastic tank was brilliant. It fit the Z with no mods. I'm guessing it was the same guy.

Was he the one who used a plastic fuel tank that fit an old Plymouth?

We used Avery at work for race cars and it did a pretty good job around complex curves. I've always heard that the S30 headlight buckets are extremely difficult to get right. My buddy Dean owns an IMSA team and this was one of the most difficult wraps he ever had done due to the chrome. It wasn't as forgiving on the contours. He said that the "hips" right below the quarter windows was all but impossible to get smooth. The cars always looked like a Jiffy Pop container in that area when viewed up close. The S30 has a very similar contour there, so certain types of wrap might be an issue. I think think this one of the best looking race cars ever though (after the BRE cars of course). It's inspired by the Gentleman Jim WWII P51 Mustang livery.

Depending on the rest of the car's theme, I appreciate them all. Black wrinkle, red wrinkle, polished, body colored, and stock can all look great. It's a bolt-on part, so it's a great part to customize.

IMHO, wrap is great for race cars and it's great when done clear as a paint protector, but every wrapped car I've seen has had the same issues which is minor lifting at the edges on convex panels. Shortly after even 1mm of vinyl lifts a hair, dirty water gets under the edge and it starts looking shabby. This will continue over the life and get worse over time. Wrap is a fantastic temporary coating. That's why it's so good on race cars. All of the sponsors and graphics can be printed right on the wrap. A good quality paintjob is still the better option for long-term durability on a street car.

As an insider that works with camouflaged cars every day, I know it's frustrating to the public to see camo on cars that have had massive ad campaigns already like the Proto Z (I refuse to call it the 400Z as I'm still hoping Nissan calls it the 300Z). At this point, the production car will certainly be close, but likely different in many small ways when compared to the Proto Z. One of two outcomes will occur. Either people will like features of the Proto Z better and complain about how Nissan dumbed it down for production or they will think the production Z looks better and Nissan's big ad campaign will be outdated, It's a no-win situation, so the best thing to do is hide the final details until it's 100% ready. The main reason for the ongoing camo though is that pre-production cars are far from perfect. These cars are not built on the production assembly line and haven't gone through anything close to production quality checks, so if a car "looks" like a production car on the street, people will assume it is and their impression will be severely tarnished if they see poor panel gaps, missing trim, mismatched panel colors or 3D printed parts that aren't quite right. Anything that's plastic would not yet be grained. Manufacturers add graining to the tooling after they are sure the plastic parts will not need to change. In addition, many of these cars started life many, many months ago before the Proto Z reveal, so they never got a real paintjob. Most get a simple black or white paintjob just to cover the metal so they don't rust - think rattle can. They were camouflaged when built, so removing the stickers now would not only reveal terrible looking cars, but much of the paint would peel off with the sticker removal. Depending on the car's intended usage, some parts are never installed and others have been removed or cut up to fit test equipment. Prototypes are not meant to look good. They are built for testing. Some are powertrain calibration, others NVH, Vehicle Dynamics, brakes, etc. The engineers usually don't see what the production car will truly look like until the public reveal. We see the same ugly prototypes as the public.

That's pretty much the point. 🙂 The sticker camo hides exact shapes from the camera lens. Until they do the production car reveal, every manufacturer uses similar techniques.