Zed Head

The timing light tells you what your timing is. It is what the light says it is. Not sure that fiddling with the distributor will help things unless you want to run with 20 degrees initial timing. That's pretty high. You could easily end up at 40 degrees at 2500 RPM which your engine might not like. Some of the 280Z distributors even have 11 degree weights, for a total of 22 degrees on top of initial. I don't really know what's happening with your problem. I'm still leaning toward vacuum leak. The Aussie Home Built Z guy just posted a video about having to run very high advance numbers for timing then finding out that his intake manifold wasn't bolted down. Big leakage. I think it's in his "Dyno day" video. Once he fixed the vacuum leak he got back to normal.

This isn't enough. The initial timing advance number needs to be verified with a light, at least. Ideally, the person doing the install would then verify both MAP and centrifugal advance by revving the engine with and without the vacuum hose attached. If you just go through their procedure and end up at 15 degrees initial you'll be over advanced when the engine is running. Actually, I'm pretty sure that there is a post out there somewhere about the install procedure not working right and having to go back to basics. Trust but verify. Without the numbers there's not much to go on.

That's what is on top of initial. If initial was set to 10 then it's 39 at 8000 RPM. Plus there's the MAP curve underneath. Ideally the timing would have been verified by a timing light.

Could be from detonation. Detonation breaks rings and ring lands. Any chance you could describe or show the advance curve that you were using? And the details of the engine? Is it stock compression ratio? Could be the problem wasn't losing advance but having too much.

You said that you made your own "booster lines". When you say booster do you really mean master cylinder? The booster just has a vacuum hose. Pedal going to 1" from the floor would not be a booster problem. The booster just adds assistance to the mechanical parts. But there is a solid metal path (with one chunk of rubber in the middle) from the pedal to the MC. Sounds more like an MC seal problem.

Numbers are always good. Report the numbers, then do the standard practice of adding oil to the cylinders to see if they help seal the rings. If the oil helps you have a ring problem, if it doesn't you might have a valve problem. And don't forget to open the throttle before cranking. And remove all of the plugs so that you get some good engine speed.

You're welcome, as is 123. They make a good product, and, obliviously, by your firsthand account, stand behind it no matter how much abuse they take from customers. That's a pretty good recommendation. They should thank you.

How do we tell who wins this conversation? I win if you find a problem that is not timing related. You win if nobody ever buys a 123 distributor again. I'm rooting for me.

The AAR does the same thing as the idle adjustment screw. You could just open up the idle adjustment screw to see if it starts and holds idle. If it works then the idle speed will slowly increase the engine warms up. It will be a good clue about the problem though.

Fighting the world's irrationality, one simple internet post at a time...

It's called a coincidence. Two unrelated things that happened at the same time. Your engine was about to die anyway, it just happened to happen right after you installed the 123.

You're "bad-mouthing" a good company, based on a lack of knowledge. I do know how engines work, and I know how to determine the cause of a failure. You have jumped to a poor conclusion and are sticking to it, no matter how much rational advice you're given. You're spending more time defending a bad position than actually trying to find the truth. That's why I'm here, to find out what really happened. I did not read your email exchange with 123. But if you communicated with them like you're doing here I can see why they gave you problems, and why they refunded your money. You just wore them out.

You haven't clarified anything for people that understand how engines work. No offense intended, that's just how it is. Loss of timing advance as indicated by the "app", smoke smell, poor running, low compression on one cylinder. Just a list of things that happened that might or might not be connected. Sorry. Your frustrated, but you're not making things more clear with your posts. Go get some real information. Confirm valve lash, check spark plugs for signs of detonation, add oil to the cylinders for the compression check to see if it's rings, do a leak down test. Do more.

If you find something like a bent valve or loose rocker arm that is causing the low compression, it's going to be awkward...

Your case would be helped immensely if you could rationally explain how timing problems cause damage that would cause low compression. That lack of reason is why the 123 guys weren't helpful. There's no cause-effect. It might be coincidence.

I'm just showing how rants almost never turn out well. Losing advance would cause the engine to run hotter and probably smell gassy. Did you smell fuel and did the engine get hot? You didn't provide any proof that the lack of timing advance caused the problem, whatever the problem actually is. You didn't actually tell us what the problem was, just made indirect inferences about a damaged piston. That's the problem with rants. So many words in the head that the important ones get left out. If you start over with just the details of the engine problems we might have a solution out here. Your issues with 123 aren't going to stop anyone from buying a 123 ignition system though. Seriously, they have too many success stories.

I would put the idle problems firstly. A big vacuum leak might have that effect. When you say it won't idle correctly do you mean when cold or at any temperature? What happens if you just open up the idle speed screw on the throttle body to increase idle speed? Does the AAR work correctly? Anyway, there are pictures out there of rotor position but I can't find them. The other way is to check the drive spindle tang.

That's the rest of the story. Apparently, he smelled smoke, then, later, he measured cylinder pressure and one was low. But he didn't spend much time talking about what the actual damage found was. " I just measured healthy compression a week ago, why would shortly after my drive a piston burn up? Issues within the distributor? Maybe this piston was on it's way out already?" It's a bummer but it might be that the cause is completely unrelated and he's jumped the gun. Too soon to assign blame.

Isn't it more likely that the engine started running poorly because of the broken cap, the driver got angry and started "beating" on the car to take out some frustration, and the over-revving holed a piston or broke some piston rings? That's the sub-text, I think. The broken cap caused the frustration which caused the engine abuse which caused the engine damage. So there is a path back to 123 but it's a stretch.

Seems like you had a confusing problem, blamed the wrong thing for the cause, tried to force 123 to accept blame for something that any reasonably knowledgeable mechanic would not accept as the cause, then they eventually tried to help you out by refunding your money with no restocking charge. At the worst, they sold another broken distributor cap. That's the only real fault here, that I see. You spent more time complaining about 123 than analyzing the problem. You even said that you can't be sure it was the fault of 123's product. Stuff happens, especially with these old cars. " Did it lose vacuum? I just measured healthy compression a week ago, why would shortly after my drive a piston burn up? Issues within the distributor? Maybe this piston was on it's way out already? Both possible and I agreed that there were too many variables to prove."

Your ignition timing, as shown by the flashing light and the timing mark on the damper pulley, and your drive gear and rotor are really two separate things. And the fact that it won't stay running at low RPM is probably not a timing issue. No offense, but you're getting things blended together. What you're doing probably won't fix your problem, unless the mark on your damper is incorrect and what you see by the timing light is wrong.

The head gasket usually tells a story. Check it carefully.

Spreading the bent part out slightly with a chisel or drift should be enough. Oil them up before removing so that they can re-expand more easily. Think of it as a machining operation. Sometimes, apparently, the threads next to the flats get damaged during nut removal. But, because there are flats next to them I don't think that they supply any real holding power. It looks bad but it doesn't matter as far as function.

Those last two are good ones. I had a 78 parts car that would catch, then let loose (catch-grind-whiiiiirrrr), many times before starting. The pin in the switch was loose. Years later after the car was long gone but I still had the switch, I figured out what was happening and restaked the pin with a drift. It had just loosened up over time. The pins that you see in the video that Dave WM supplied. You could wiggle the loose one with your fingers. You can just see the staked ends also in the first image, above.

This part of their ad copy suggests that you'll get more road noise. They must have tried it on one of their own cars. Disappointing. It's a solution to a problem that people just don't have. Pretty expensive too. "Note:This kit will increase feedback felt through the suspension, and may increase road noise and vibration a bit (almost all suspension upgrades do to a degree). Based on overall design and quality of the pieces, we do not think it will be all that significant for most Z-Car owners. "