jonbill

I agree, think that timing cover is going to have to come out to remove the debris and straighten the key.

The woodruff key is present on the crank, so the crank pulley can only go on in one position. And if the engine is at TDC then the crank pulley is in the right position and maybe the pointer is in the wrong position. on earlier engines, the pointer on the timing cover and the pulley marks are on the left (10 oclock) at TDC and on later engines, they're on the right (3 oclock). so it sounds like you've got an early pulley with later timiny cover/timing marks.

that seal doesn't look right to me - is it the same size as the timing cover hole?

I'm afraid I don't know your setup and how its adjusted, but yes, I'd be trying to get it at least to mid 13s.

well, depends on your gearing of course, but typically 2500 to 3500 rpm. But you do need to measure it on the road - it's not valid if the engine has no load. (just checking!)

I would yes, unless you've got to get through a strict emission test, in which case aim for 14.7 at idle. Modern OEMs run leanest at cruise - lots of ignition advance and a little leaner than 14.7.

TBH those values look pretty good. I wouldn't go leaner than low 14s at idle. Mid 14s at cruise, no need to go leaner unless you're doing big mileage and want to save a few pennies.

What sensor can you put in the inlet tract to measure the air/fuel ratio?

thats too far in, should sit flush with the outside face of the timing cover. I think thats in danger of falling in!

Thats partly true. as I said, if you don't have a high enough energy coil discharge, the spark won't be able to jump a 1.1mm gap. so you could buy - 11 plugs for that or regap any other plug. The heat rating of the plug (5,6,7 etc) is dependent on combustion pressure and temperature, not so much the ignition system.

In the same way that taking your temperature is a reliable indication of whether you have an infection.

The residual oxygen in the exhaust is a reliable indicator of the ratio of fuel and air at the inlet. This is true given a working and reasonable ignition and cam timing. Engine Management systems do work on this basis. I mean, as well as that being an assumption they make, they actually do work well in optimising fuel mixtures.

I think its mainly a function of the coil and the voltage. points running at only 8v, there's not enough energy to jump the gap at peak cylinder pressure. start at 1.1mm, and if you don't misfire anywhere in the rpm range, leave it there and be happy. if you misfire around peak torque, close the gap a bit until the misfire goes away, then leave it and be happy.

I guess you know the Dupuytren's is fixable, but not the arthritis. what you need is a younger keen relative who'd like to inherit it. you can be the brains and they can be the brawn.

I did read on the speeduino forum that 1 wire sensors don't work well. I think just getting a later thermostat body with more holes would be best option.

Sorry, I've never seem that system 🙂 what happens if you unplug that switch?

can you describe what you've got in a bit more detail @jas. you've mentioned EGR and water temp switch, neither of which I'd expect on a 72 carb car.

got a pic of your spark plugs?

Does your thermostat housing not have a blanked hole next to the standard sensor housing? mine does, its a standard size, m12 maybe.

The Zclub in the UK has a thread on seat upgrades at the mo with some interesting options. https://zclub.net/community/index.php?threads/seats-again.27924/

standard gasket is 1.2mm installed.

they don't have struts, but they do have strut inserts : https://www.thezstore.com/page/TZS/CTGY/classic20b04

must be an electrical problem. Maybe your alternator is over or under charging?

If it was smokey, make sure you change the valve stem seals. Maybe even check the guides aren't too worn. It won't be the compression rings.

not only will it take a lot of filing, I imagine it'll be under quite a bit of stress, being that compressed. And if the bore isn't round, it'll still not seal, as @zedhead pointed out.