Captain Obvious

Thanks for the additional insights Jeff. About the eccentric bushing... My plan is to put the stock cam back to the stock valve timing using the original timing marks. For the bushings, I'll come up with a simple fixture to press the bushing into place (off the car) and locate the holes for me. So the difficulty of turning the bushings once installed won't be an issue. In the end, even though I'll have the ability to change the bushings to mess with the timing, I wasn't planning to do so. The only reason I was going to use the bushings was to account for the timing change incurred as a result of cutting the head. But once I get it set back to the stock timing, I wasn't planning to mess with it (ever?) again. The plan is to pick a bushing while I have the front timing cover off and hopefully be done with it. Pulling the gear off to change bushings shouldn't be a big deal. And at this point I'm planning to put the stock cam back in and run the stock EFI, so it sounds like your street Z. When you say that this 9:5 motor is better than your 10:1 street Z motor.. . Why is that? Just raw power?

Awesome! Glad it's running well. I'm a long way behind you, but I hope mine turns out as well!

Yeah, I could just use the drill press, but the lathe would be more accurate. On the lathe I can index the part to be spot on and it also doesn't mind the interrupted cut so much if you cut through the wall into the center hole. I can also size the hole so the bushing is a slight press fit into the hole. I'm not quantized to drill bit sizes. And that's a great piece of warning about the bushings being thinner than the gear. What I can do on the lathe is mount the gear back side out and bore from that side. I can control the depth of the bore so it doesn't go all the way through the gear. That way I can leave a shoulder in there to keep the bushing from possibly walking out. Easy peasy, but I didn't know that until you brought it up! For fuel delivery, at this current point the plan is to redress it back up with the stock fuel injection. I suspect I'll have to tune the system a little, but I'm hoping that will work. I've heard that the stock system doesn't adapt well to modifications, and I guess I'll be able to confirm or deny that accusation. That's the current plan. If that fails, I'll throw on a pair of flat top carbs or maybe an aftermarket EFI system. Your 9.5 compression ratio sounds pretty much in line with my calculations. I came up with about 9.3 at .040 off. Thanks so much for the info, I appreciate the details!

Thanks much. There's lots of other stuff I need, but it's not the kind of things I can lean on vou for. Bigger stuff like gasket set, rings, head bolts... You have a pair of piston ring pliers or a ring gap grinder? I don't have that stuff and I'll probably only ever use them this once. And I'd love to fight over another lunch bill. My house is your house!

Thanks Jeff, my confidence in the plan grows. What you did to your head is pretty much what I was planning to do with mine. I was thinking I would go .040 off rather than .050, and that should make my timing chain tensioning mods just that little bit easier than yours. And I don't know if you read this part of the previous pages, but I've already verified that I can chuck the cam gear up in my lathe and I have enough swing to index it to the side and bore out the original dowel pin holes for the eccentric bushings. So I'm confident that I've got the valve timing issue under control. In case you missed that part... Cam gear on the lathe. Indicated to a fraction of a thousandth on the original hole. I didn't cut anything yet, but I'm confident I can when I need to:

Thanks bud! That would be fantastic. I've been making up a list of parts that I'll need for this endeavor and anything I can cross off will help. Let me know what the shipping is and I can at least cover that!

Great trip. And you made me look up that reference. Not sure I ever saw that one!

Haha!! Nice!

Well therrrre's your problem. Glad it was a non-issue.

Oh, and forgot to tell you before... The prevalent info on the web says that the original thickness of the Z heads is 108mm, and I've verified that's what mine measures. I measured the overall thickness of my P79 and it's 4.255 inches (108mm) thick, so my head has never been shaved. If you check yours and get the same number, it'll be another data point to indicate that your motor had never been open before.

I grabbed a couple quick pics off ebay... Here's the back of a Beck Arnley aftermarket pulley. See the three timing mark gashes cast into the back side: And here's the back side of a Federal Mogul Sealed Power. Note that there are no timing marks, so you'd be assuming the timing is where you want it: Some of the aftermarket stuff has the timing marks and some do not.

I'll dig up some pics of the aftermarket sprockets. My suggestion is to get one that DOES have the timing mark gash on it. If it doesn't have the timing marks on it, the only way you'll be able to verify your valve timing would be to use an indicator to degree the cam. And nobody wants to do that.

Thanks Diseazd. It's my assumption as well. That the manual trans flywheel bolts are longer. And I've got a pilot bushing on my parts list of thing I'll need. And Zed Head, thanks for posting the pic in the parts breakdown.. It pointed out #22 PILOT-CONVERTER - 12330-E3000. I had not noticed that on there before. I would have figured it out as soon as I tried to get the rear main seal off the crank, but it's better to discover that now rather than be surprised by it later. Here's #22 sandwiched between the flex plate and the rear face of the crank. Give it a twist (as can be seen by the holes that don't line up anymore): and a pull, and it comes off the back of the crank. They only use this on the auto versions:

Well I don't know if all the auto's looked like this, but this is the trans plate I've got from my 83 auto. Two pieces: And there were some sort of brackets at the bottom of the bell housing. Probably some sort of stiffener members to account for the huge torque increase from the later year motors . Two aluminum brackety things : The look like this when installed:

Not a chance. I wouldn't do well at all. The only position I would be even remotely fit to fill would be grabbing them by the covfefe.

Haha! I've got calibrated eyeballs. That, and it's easier to spot it when you know what you're looking for. The 82 cam gear looks stock to me. Looks just like the three ZX pulley's I've messed with in recent past. They went to the eight hole version some time between 77 and 81. They also changed if from a sand casting to an investment casting (not that anyone really needs to know that), which accounts for the change in surface texture. Now, as for your 77 cam gear, I'm not sure. My 77 gear has four holes, so it's different than yours. But dies wear out, so it's completely conceivable that yours is stock, just from a previous die revision. They're always trying to cut weight, waste, and cost. Some (most?) of the aftermarket gears don't have the little timing mark gash on the rear. So by virtue that it's got the timing gash, I'd vote for stock. My non-expert tips on pulling the pistons out... Pistons come out the top (just sayin'). And make sure you carb cleaner the carbon ring at the tops of the cylinders completely clean first. Don't want to push the rings over that hump. Don't use anything abrasive on the cylinder walls (don't use sandpaper to remove the carbon ring). Push the pistons out slow and evenly. I have seen a few very rare occasions where a piston ring will break when it snaps out of the bore. So if that happens, don't freak. Did you find the block numbers? Here's a pic of one of my ZX pistons and the corresponding stamp on the block. Piston: And the stamp on the block. Left side right next to each cylinder bore. All my pistons were #2 and all my block stamps were 2 as well:

So my ZX motor came out of a car with an auto trans, and I've got a couple questions about that... First, I've noticed that the thin steel plate that goes between the block and the transmission is different. The manual version is one piece, but the auto version uses a two piece version with a separate small piece that bolts into place on the bottom. They did that so you could access the bolts that attach the torque convertor to the flex plate. Question is... Can I use the auto version with a manual transmission, or do I need to source one of those plates? Second, Are flywheel bolts the same as flex plate bolts? I'm guessing that the flywheel is probably thicker than the flex plate and used longer bolts, but I'm sure someone here has been through all of this before and knows off the top of their head.

Non-unretouched photograph:

I did guarantee it! Hope it's not too bad. I've got a soft spot for the early 260s. (And as you've found... The early 260's have soft spots).

Haha!! Fair enough. Hope it comes together!

Cool! Standard size stock pistons! I can make out the P79 on piston #6, along with the 34 marking (large "3" and smaller "4") to indicate stock bin sizing. I'm assuming that if #6 is stock, then the rest of them are as well. There should be a "3" stamped into the top surface of the block next to that piston. I can't make that out because it's hidden under head gasket residue. Clean all the pistons up and clean off the block deck and you should be able to see all the numbers. Nothing else really catches my eye, Looks like a completely appropriate amount of carbon for a used ZX motor. Should clean up well. I'll measure the thickness of my head and you can do that same. I'm fairly confident that mine has never been shaved, so you can use that number to check yours too. I've looked at four head gaskets recently from different origins, and all four had manufacturing markings in the same spot... The rib between piston #1 and the timing chain cavity. Like this: Take a look at yours and see if you can find any marks. If it's aftermarket, it'll tell you that someone had been in there before.

LOL. Well if you ask me, the problem isn't the balance tube. The problem is that you removed the flat tops. Good luck with the project. Too bad you won't get to enjoy it much this season.

Here's the rub. You asked about a moved link... The point is there was no moved link. You moved the sprocket, not the link. All the links stayed in the exact same location. All the links that were on the tight side before the sprocket change are still on the tight side All the links that were on the loose side before the sprocket change are still on the loose side. You did not move any links. You carefully took off the sprocket without disturbing the chain position, rotated the sprocket one link clockwise (without disturbing the chain position), and then put the sprocket back on (without disturbing the chain position). The links never moved. At all. Ever. After the move, there will be 41 links between the default dots rather than 42 links*. But not because you moved a link. It's because you moved the sprocket. * Note that I have never counted them to verify that number. I'm counting on you for the accuracy of that.

LOL!!!

There were originally three paths for water to go through the flat top carb system. 1) First was through the carb bodies themselves. Those have already been removed since you are now running round top carbs. 2) The second path is through the intake manifolds. Inlet you have labeled #1 and outlet labeled #2. Since they are disconnected from any water source, you can plug them, remove them and plug the resultant holes, or simply leave hang open. 3) The third path for coolant is routed through the balance tube. Inlet comes up from underneath the two carbs about in the middle. It's the flare style nipple at the bottom of this pic: and the outlet is what you have labeled #3. That outlet pipe #3 is rotated 180 degrees from where it's supposed to go. It's supposed to go around the back of the head and tie back into the water pump inlet. The other thing in the pic above (#5) is your original idle speed control. Again, since you have switched to round top carbs, that thing doesn't do anything anymore (assuming you have it tightened down completely). You can plug, remove and plug or leave it as is.