Arne

Not by today's standards, no. Actually, I think the highest compression for any of the L-series engines here in North America was 9.0:1. There were at least 4 major versions of heads which carried the E88 casting number. Late '71 were very similar to the E31 combustion chamber, but slightly lower compression, had a CR of 8.7:1 or so. '72 had a different combustion chamber shape, and a CR a bit lower yet, about 8.3:1. (Sometimes called "small-chamber" E88.) '73 changed the chamber shape yet again, CR about the same as the '72, maybe a touch lower. (Sometimes called "larger-chamber" E88.) '74 was much the same chamber as the '73, but had larger exhaust valves.

No, I'm anal and a more than a bit fussy. My carbs' screws are all still pretty pristine and yellow cad plated. I do it VERY carefully.

Removing the domes is pretty darned easy, about 2 minutes per carb. I don't see what the big deal with that is.

Mine is currently much like yours, Gary, except that the original out pipe was cut off at the exit of the "Y" and a new, shorter one welded on. My entire exhaust from that point back is rusty mild steel, crush-bent 1 3/4" pipe. The glasspack is 24" long, and was welded in like yours, only a much cleaner welding job. As for what I replace it with, I keep waffling. I like the exhaust note now, but it could stand to be a touch louder, even in my wife's opinion. I don't care for the look of the small rusty tailpipe with cheap bolt-on chrome tip, and it might be nice if the pipe was a bit larger diameter (both better flow and louder). Aluminized pipe would stay better looking for a much longer time. I also want something that looks period correct. So I haven't firmed up my decision yet. I've considered that NOS Ansa that Clive has for sale, but by the time you factor in shipping to Oregon, that's $500. More than I really want to spend on an exhaust, plus the few Ansas I owned back in the day were not very durable, rather rust-prone in fact. It would be period-correct, though, not just period-looking. Another option would be a Monza system. That would look period, but with the modern aluminized pipe and mandrel bends that the Ansa lacks. But I'd need to re-work the out pipe on the downpipe to match the front of the new mid-pipe (have to do that for the Ansa, also), and the yellow paint in the tips would have to go for my red car. Cost would be about $300 delivered, or $200 less than the Ansa. Or I could have the existing system recreated using larger, aluminized tube. Say 2" or 2 1/4" pipe. Mandrel bends would be nice, but not necessary if the extra cost is too much. Still use a glasspack in the middle, but use a nice resonated angle cut tip on the end. Probably have it built with flanged joints so that it could be dropped in sections for servicing the transmission or rear suspension. This is probably the most likely option. Price would be similar the Monza, I suspect.

Have you already test fitted it all to the car? You'll want to have the spook mounting holes drilled before paint. You don't want to drill through the fresh paint.

My info came from my Nissan FSM. Calls for 0.8-0.9mm (.031-.035"). I'll trust Nissan before I trust the plug manufacturer.

I don't know about a '72, but the recommended gap for a '71 is only .032", not .040". In my experience, wider gap is not better, at least not for a 240Z. Many NGK plugs have the gap that they preset as a suffix to the part number, in tenth of a millimeter. (1/10th mm = .004") So a BP6ES-8 has a .032" gap. a BPR6ES-11 is .044". If a plug doesn't have the suffix, assume it to be -8.

It's not cheap, and generally includes bigger brakes so that you need bigger than 14" wheels. Or that's what I've seen. Others may have more experience with this and should chime in.

Take a peek under the rear to see how much room you have between the tire sidewall and the springs. To go from 215 to 245 you'll need at least 3/4" clearance to the side, and probably a 1/2" upwards. Konigs have -9 offset, that will help on the side clearance. You could have adapters custom built to take those Cragers, but they'll be expensive and custom. Cheaper to find a set with the more normal 5-4 1/2 bolt pattern. Adapters for that could be purchased off the shelf. But adapters will add 25 mm negative offset, which is a lot. You could also convert your hubs to 5 lug so you could run similar Cragers. That would be the best option.

Clogged fuel vent or flow guide valve? Try running it with the gas cap off or loose?

Done. #99. Almost to 100!

British SUs, as built by Skinner's Union, as opposed to Hitachi SUs built under license. My MG had brass damper caps.

Oops! You're right. My bad. Worn, incorrect, bad or improperly adjusted needles, I'd guess. Float levels too high might affect that too.

Hmm, I haven't got there yet. In fact I actually find "working on 30+ year old cars and....sourcing parts for them" to be almost as much fun as driving them. Recreational and takes my mind off work. In fact, that was the problem with the MGB - restoring it and hunting down the correct parts was much more fun than driving the finished product. Not so the Z, so I can't yet foresee the day I'll want to sell mine.But those days do come for many of us. They're only cars, and when they fail to be entertaining, it's time to move on.

The one I was trying was not broken that way, I had seen that page before and checked. But that's another point to look for (in addition to worn shaft bushings) when looking at a used ZX dizzy. I agree that there are several potential advantages to a ZX dizzy over the smaller 240Z unit w/Pertronix. But my uses are mild and my L24 is stock, so the Pertronix choice was simple and works great for me.I recall that beandip had instructions on making a simple travel limiter for the ZX advance mechanism. that may be something to look into also.

After looking at the pictures in this thread closely, I'm now pretty certain that my downpipe is original down to the outlet end of the cast/stamped Y. From the outlet of the Y back is custom. All the pictures here show the pipe going to the rear a ways before turning in to follow the tunnel back. Mine turns to the center almost immediately after exiting the Y. So since it has already been buggered by the original owner, I feel OK with whacking that part off (after the Y) and doing it better than now. Still don't know if the Y is cast or stamped, but leaning towards stamped. I'll try to get under the car this weekend to check.

I also use NGK wires and they seem just fine. Other good brands for L-series are Taylor and Magnecore. But the NGKs are fine and far more affordable.

Done. Pin #98.

Then 205/60-14 should fit fine, and probably 215/60-14s as well. With the wider size my concern would be on the front while turning, at the front valance corner. But if those awfully tall 205/70-14s don't rub there now, the 215/60-14s shouldn't rub either. More tire selection in 205/60-14 though.

Well, at this point I'm going to work on the assumption that mine is (at least mostly) original. (I'll explain the 'mostly' part next.) But considering how many early cars we see here with the other style, the thought that Nissan may have had two suppliers is looking fairly good. As an example, while many of us know just how rusty Jim's car (a7dz) was, and that it seems likely that the exhaust could have been replaced due to rust at some point in the distant past, on the other hand, he doesn't remember it, and that unique 'Z' or 'N' badge on it gives pause. So either type might really be correct. We may never know the details for certain. To Geezer - I don't know if it is cast or stamped. Kats' site refers to it as cast, but that may be an artifact of translation. I've always assumed mine is stamped in two halves and welded. I'll need to get under the car and check closely to determine which method was used. As for my 'mostly' original comment - all this has me reconsidering just what I have under there. The original owner had the exhaust re-worked early in the car's life. He apparently didn't like the way the stock exhaust sounded. The exhaust is all welded into one piece, downpipe to glasspack in the tunnel to a long tailpipe out the back, all of it 1 3/4" pipe, as I recall. I've always assumed that the muffler shop cut the old off just behind the cast/stamped junction and welded new on from there. Looking at Kats' pictures, now I'm not so sure. Now I wonder if the entire stock downpipe was retained and the glasspack was welded to the end where it would normally mate with the center resonator. If I can determine that to be the case, I may want to retain as much of the downpipe as I can, by removing the glasspack and building from there back, rather than building from the junction back as I thought had been done last time. I guess I'll need to find time to crawl under the car this weekend....

No knowledge of the Nexxens. As for size, do you have any idea how much the car is lowered? Do you have an air dam, or stock valance? And when you say you have "Iron cross" wheels, are they the 14x6 280ZX wheel, or the earlier 280Z 14x5.5 wheel, which is different but some people also refer to as an "Iron cross"?

OK, so Jim's car has the same type as Mike's new system, and Jim knows the history of that car from new, so we can assume that it is original to the car. The other used one that Mike has appears to be an original, but we probably can't confirm that. I'm fairly comfortable in saying that mine is original too, considering the low miles, lack of under car rust, and all the rest. Mine also matches 26th's. Conclusion? I'm thinking now that Nissan got downpipes from more than one supplier. It might be totally hit and miss as to which style a particular car (or batch of cars) got.

Stephen, I now think that would be a good idea. Problem is that none of the many guides to installing a ZX dizzy on an L24 make mention of the delay valve. I'd never heard of the device until long after I gave up on the ZX ignition, for pretty much the same reason that Steve describes. I suspect that the lack of knowledge that they exist is the main reason no one uses them. Steve, as I mentioned above, I gave up on my ZX dizzy. I believe that mine was from an '83 automatic, but had the earlier E12-80 module. But I had to use 93 octane fuel and drop back to 5° BTDC or less to keep it from pinging under moderate load at highway speeds. I went back to the stock 240Z dizzy with a Pertronix, and am back to 12° BTDC now with no detonation, and will experiment with a bit more advance or maybe lower octane fuel shortly. I didn't do any measurement of the total advance on the ZX dizzy, but came to that same conclusion just from my testing.Of course, not everyone has an original 240Z dizzy that's not worn out like I did, so my alternative may not work for a lot of people. But I do agree that the vaunted ZX ignition is not a totally trouble-free option in all cases. Adding the delay valve that Stephen mentions is probably a good option, if they can be easily sourced. Or re-curving the ZX dizzy is another good choice, if people can find a good place to get that done. But considering the advancing age of even the newest of the ZX dizzies, and the number of those that by now also have worn shaft bushings, I'm wondering if the simpler option might soon be to buy a remanufactured 240Z dizzy off the shelf and stick a Pertronix in like I did. A bit more expensive than a ZX dizzy from the pick-n-pull, but perhaps a better choice in the end. I can't remember Steve, are those carbs still original? Not remanufactured? In theory, the whole approach of the SU design is to keep the ratio fairly steady through-out the rev range. If the idle mixture is way richer than under load, one thing I'd suspect is a vacuum leak at the throttle shafts. With a vacuum leak, one of two situations occurs: you can tune them either rich at idle/good at speed; or good at idle/lean at speed. If my carbs were worn, I'd want to have mine set like yours rather than lean at speed.So it might be worth checking the throttle shafts for vacuum leaks.

My thoughts are similar. It sounds like the rear carb isn't working to me. As mentioned, check the rear carb piston to make certain it moves freely. You mention the float height at the front carb, what about the rear? Has that been checked?

Thanks, Dan. That is the type on my car, built in 7/71. So are we trying to decide that all the ones pictured in this thread (Mike and Jim's) are later replacements, not original to the car? Or that mine was replaced with an earlier type later in life?Direct link to the pictures on Kats' webpage.