Zed Head

Damn. No wonder you've been quiet. I cut the tip of my finger off many years ago and a doctor sewed it back on. It was just a 1/4", not even any fingernail. Took many years until it stayed pink when it got cold out and softened up like a normal fingertip. My grandfather had a perpendicular thumbnail, from chopping his thumb-tip off right at the base of the nail while splitting wood. Pretty sure where he lived at the time if you couldn't sew it back on yourself you were out of luck.

A hockey puck might be the same material as the original coupler but I'm pretty sure it's a lot stiffer. Probably better than the ABS piece, but might not be that different from PU. Weird how the use of PU in certain places has tainted its use everywhere else. But it's also funny how the use of PU in one place led to its application anywhere else it could be jammed in. I still have my old coupler but it's starting to feel like a valuable antique.

I thought you asked him about the progressive rate springs. His answer seems boilerplate for installation. Irrelevant to performance though, and installation in your case. He did have some issues as noted earlier. I'd guess that these are low volume parts compared to his other products, so he probably doesn't have a ton of time for them. John Coffey died in a motorcycle accident a few months ago. He did comment in the past though, over on Hybridz, that he was only doing both sides a favor by telling about the new products. He didn't have anything to do with their development.

I know that MS used some odd labels for their sensor circuits and often recommend using input circuits that don't seem to match the type of signal being acquired. But Matt Cramer is familiar with all of that. Have you been into the MegaManual yet? Probably worse than digging up old BMW wiring diagrams. The search box is your best friend... http://www.megamanual.com/mtabcon.htm http://www.megamanual.com/v22manual/mwire.htm http://www.megamanual.com/ms2/pickups.htm http://www.megamanual.com/ms2/vradjust.htm

I found a STD Repco. You're probably right on the 020. Probably .020". 20 thousandths. http://www.ebay.com/itm/Set-of-4-New-Standard-Size-Repco-Pistons-w-Rings-Pins-Fits-Datsun-510-521-/311549667486?fits=Make%3ADatsun&hash=item4889cea89e:g:BnsAAOSwll1Wuz66&vxp=mtr

Many (most?) overbore pistons come with a stamp indicating size on the top. STD, .010. 020. etc. Nissan might use 0.5 mm, 1mm, 2mm. Any marks on yours?

Up or down won't matter, but I'd worry about the spring rates (see earlier in this very thread. I should have posted the Hybridz link). Hope it works for you.

They have different part numbers. Doubtful. I've never had an R180 though. http://www.carpartsmanual.com/datsun/Z-1969-1978/power-train/differential-gear

You're the guy that tears things down to figure out how they work! The tech probably took your tire to the back room and used one of these on it - https://www.amazon.com/Black-Iron-Tire-Repair-Plugs/dp/B019FZMIDM/ref=sr_1_27/168-6815766-1608455?s=automotive&ie=UTF8&qid=1470792775&sr=1-27-spons&psc=1 I have several in my various tires right now.

I think that just replacing a few valve seats can distort the others because the seats are cut to fit the valves after they're all installed. The seats are an interference fit so they distort the aluminum around them. One thing leads to another...

I don't know the L24 and L26 world well but the engine calculator I use suggests that an E31 should swap right over with just a small bump n compression ratio. 8.3 to 8.5. Same valve sizes. Here's one in San Jose. still has the brass seats and might have other problems. Just in case you find a major problem with the E88. http://sfbay.craigslist.org/sby/pts/5721622083.html http://www.ozdat.com/ozdatonline/enginedesign/ This is how we end up with a car we can't drive in the garage and a less full wallet.

I wouldn't say it all goes away. It's just reduced. PU is definitely more compliant than ABS. I have the PU rack bushings too. I installed the rack bushings and the coupler because I wanted to tighten up the steering. But, I do have one of those spongy steering wheel wraps over the stock 280Z rubber. I'd imagine that if you have a 240Z wheel with wood or some sort of aftermarket wheel, you would get more road feel. Follow the path from hands to road. And we should distinguish between high frequency, like a rough gravel road, and low frequency, like a bumpy road, and shocks, like banging a small pothole, And hand size. Donald Trump probably needs all rubber. Kidding!! Really, all you can do on these questions is recommend a direction. One person's firm ride is another's rough ride.

MSA sells an ABS coupler ($13) and a PU version ($15). ABS is definitely a hard stiff material, like black sewer pipe. PU is in between ABS and rubber in stiffness. http://www.thezstore.com/page/TZS/PROD/23-4161 http://www.thezstore.com/page/TZS/PROD/23-4160

You live in a very very expensive region of the country. If you really want to get it done, you might see about driving a few miles out of the area. I live in the Portland OR metro area and I've found that I could save a lot of money for machine work (driveshaft shortening, for example) by driving up the Columbia River gorge about 30 miles. City living is expensive. Definitely seems like a lot for a head you don't really want. You could buy a complete L28 for that money around here.

Not sure why people don't like the polyurethane (PU) unless it's a combination of factors. I have the PU coupler, with 205 70/14 tires, cut springs (about 1" lower) and KYB shocks. Feels great, no shocks or harsh road feel through the steering wheel. That's with PU T/C rod bushings (front, rubber in back). The PU coupler is inexpensive and easy to change. Worth a try, I'd say.

Same vein - check the separator between the two sides, the exit tubes, in the exhaust manifold. I bought a ZX engine and that separator was complete rotted away. One giant cavity. Make sure the parts are worth saving. I also spent a bunch of money having a manifold resurfaced and a stud removed. The guy went to the maximum of his estimate range (of course?), he couldn't let the broken stud beat him. I paid the price. Should have just bought a wrecking yard replacement. Didn't know better at the time.

Just thought of another trick I've used to put in as little heat as possible, to avoid unintended damage like warpage. Put tension/torque/compression on the tool used to do the pulling/turning/pressing. Up to the limit before you think think things will be damaged. Then apply the heat. When there's enough heat things will move.

Good luck on the studs. I used MAPP gas myself, just takes a little more waiting. Check the back side of the stud holes, one or two of them might have broken through during tapping. You can get a bit more thread penetrant in that way. I had one stud that absolutely would not come out. There was 1/4" left to grab on to. I drilled a hole completely through it and squirted more rust breaker in that way. It was one that would only move when the manifold was hot, even after several rotations. It squeaked. They key to removing broken studs is anger control. So tempting to just say "screw it" and bust the remaining stub off with a twist. Then you're really screwed. Check that manifold surface for flatness. It probably needs a resurfacing. Don't remove too much, the retaining "washers" have to bridge the gap to the thickness of the intake manifold.

It probably was not the diameter of the pipe that gave the sound. There must have been a muffler involved somewhere. 3" is probably also overkill for a stock L28.

I was kind of wordy. My basic point is "match the set of parts by quality and life expectancy". If you install new seats to last 20,000 miles (2 years) but the guides are only good for 5,000, you're not getting what you thought you were going to get. The way to do it, I'd say, is to inspect everything, make a list of what's needed and what gets you where, and execute a plan. And if you have an undesirable head, you might not want to spend any money on it. I'm just the voice of economy. I ran my coolant leaking N42 head for 20,000 miles on two cans of Barr's StopLeak, instead of pulling the head to replace the head gasket (when I would have also found that the head was warped). Then replaced the whole engine when I got tired of it and was sure that my spare engine was in much better shape. I was in your boat at the time. Low cash flow.

Seems like you might be getting ahead of your self. You started out simply cleaning up some valve seats now you're about to replace them. But you haven't really inspected the rest of the parts. Might not be worth new seats. After you check the valve guides for wear, and the valves themselves (the stems), and the cam lobes and the rocker arms (you know which rocker arm goes to which lobe, right?, hope you didn't randomly disassemble), and add in the cost of new valve seals, you might decide that the ten thousand miles still left in those old worn seats will get you by until you have the cash to do a complete job.

Did you get this book yet? It's pretty good. https://www.amazon.com/Performance-Fuel-Injection-Systems-HP1557/dp/1557885575 https://www.diyautotune.com/product/performance-fuel-injection-systems-hp-books/. There is a variety of areas that people have problems with - computer technology to connect to and program MS, the fundamentals of EFI, how to get their parts to work with MS, etc. MS projects are multi-disciplinary.

Ahhh...that was not clear at all. You recycled the PO's ad. When you put your "south of Olympia" at the bottom of the ad, it used the CL font, not the classiczcar's default font. Looked like it was part of the CL ad. So what's the new price? The Kingston price from the PO or do you have a new one? You really should make a new ad.

I've studied it but don't have it. You could just throw things out and see if the bounces make sense.

I've read that the stock manifolds flow pretty well. It's the pipes after the manifold that offer the most potential. Bigger from the manifold back. It would be a bit pointless to go with headers but stock size pipes to the back. No offense to those that have done that. Those three exhaust studs are really difficult to remove. If you try it use lots of heat. I've had some that would only move when everything was hot. As it cooled I couldn't turn it any more. If they look like they'll last a while just clean up the threads and leave them. You'll probably break them trying to remove them.