It's been a while since I posted an update on the restoration! I have been driving the car - I have 488 miles on it. I reset both front and rear floats using the method in the factory workshop manual. To do so, I cut some "3d" finishing nails to the approximate lengths of 14 mm and 15 mm and then finished them to size with a benchtop grinder. The procedure from the factory workshop manual:

Holding the assembly in its installed orientation (not upside down), I first place the 15 mm nail section in between the flat metal part of the float and the underside of the float chamber cover. I put it in place using needle nose pliers so that it is straight vertically. I pinch it to hold it in place by lightly squeezing the float and the chamber cover together. Note that when held in the installed orientation, the needle in the needle is in "free fall" and is in a fully open position. Then, using a magnifying glass, I inspect the area of the float tab and the tip of the needle. I verify that the tip of the needle is not touching the curved arm (tab) of the float. It does have to be within 1 mm of it however. If not, when you swap to the 14 mm nail section, the tab will still not touch the tip of the needle. I adjust the tabs so that both carburetor floats contact the tip of the needles with the 14 mm section of the nail in place.

Interestingly, after I had set the floats this way, I noticed that with the 15 mm section of the nail in place, I could blow through the fuel inlet tube, and with the 14 mm section of the nail in place, I could not. So, what I found was that from fully open, to seated, the needles have less vertical movement than 1 mm.

While I have been driving the car to break the engine in, I have been looking at air fuel ratios (AFR) using a wideband 02 sensor. I swapped from what I believe to be stock N27 needles to some SM needles. But, I have observed AFRs moving around a bit which is unusual and not expected, and which I think may be due to the engine still breaking in. I started a separate thread that details more about what I was doing and seeing here: https://www.classiczcars.com/forums/topic/69292-choosing-an-su-needle-if-i-have-needle-station-info-and-real-world-afr-can-i-use-that-to-find-the-right-needle/

This weekend I plan to do a leak down test on the engine to confirm break in is complete, change to standard oil (instead of break in oil), and adjust the valves. If the engine is fully broken in, I will do some more AFR testing and determine how to proceed. I may need to modify the SM needles in the cruising and pick up stages by some very light "sanding" - removing material by chucking them up in drill and using 2500 grit sandpaper only in a certain area of each needle.

With the driving I have done, I also noticed a vibration at higher speeds. I started a separate thread for that issue: https://www.classiczcars.com/forums/topic/69334-how-vibration-free-is-your-70-71-240z/#comment-675670

Today, I am going to buy a digital angle gauge so I can check some angles in the driveline. I am hopeful doing this will help me determine the cause and fix that issue.

Edited April 18Apr 18 by inline6

The odometer clicked over 500 miles on Friday night, so I took the valve cover off yesterday and did both the leak down test and adjusted valves. Here were my leak down percentages:

#1 = nearly 4%
#2 = 2-3% closer to 2
#3 = 4%
#4 = 4%
#5 = 3%
#6 = a little over 1%

For my Iskenderian cam, the valve lash is .006" on the intakes and .008" on the exhaust. I set each so that the feeler gauge was a snug fit while the engine was cold. All of the cam lobe surfaces looked great!

The next time I fire it up and get the oil warm, I'll change the oil.

Today, I removed a portion of the exhaust and the driveshaft and measured the angles of the front engine dampener and the pinion flange on the differential.

I believe I will be able to lower the transmission rear crossmember to bring the engine/transmission assembly to the same 87.1 degrees that the pinion flange is at. I will just need to add shims between the transmission crossmember and the car body. Oh! And I just remembered that I should check the angles in the horizontal plane (not just vertical) as well.

Edited April 20Apr 20 by inline6

I put the progress dealing with the prop shaft and transmission and differential angles in another forum thread.

While I was repainting the driveshaft, I also painted the front grill. The front grill, rear tail light trim panels and the hub caps all share the same paint. I bought the paint for these near the beginning of my restoration. If I recall correctly, I told the paint supply place the info for the color that is in the How to Restore your Z Car book.

I painted the grill, but the color was too light - it was too grey, at least comparing to my original, not repainted hubcap. I got some crap in it too. So, repainting was necessary. This time, I took a guess, and added 10% of black paint (by weight) to make it darker. I think it came out a bit too dark, but I like it a lot more than what it was.

I think I will experiment a bit more with it, adding maybe 5% of black and seeing how that looks. Then, I will repaint the tail light trim panels and possibly the hub caps as well.

I installed the front grill today. As you can see, the paint is a little darker than the original, but I am not interested in painting it for a third time, especially since I have a wrist cast for the next six weeks. Interestingly, when in the sunlight, the original paint does appear to be metallic. The metallic particles seem smaller, less noticeable, but they do reflect. This is not easy to capture in a photo (second pic here):

Original grill hardware:

Edited Sunday at 05:57 PM3 days by inline6

On 11/14/2023 at 10:40 PM, inline6 said:

I think I figured out what was up with the tie down hooks.  Speaking of which, don't you find it odd that these cars had these? I mean, it strikes me as a very unusual part to be on the car.  Did other cars (foreign or domestic) of the same vintage have these?

The one on the left of this picture, I put on the front of the car.  It is actually for the left rear.  Note that the middle one appears to be larger than the other two, with the hook part being more "open".  Well, that it because it has been forced open.  Perhaps this occurred at some point in the car's time on the road - someone pulled the car out of a situation... using this hook, and that bent it.  I squeezed it in my vise to close the hook opening, and used my hydraulic press to correct the "bend angle".  This worked very well to put it back the way it was originally.  I'll add a pic later, but it looks just like the one on the right of this picture now.  Either of these two can be used for the right rear, or the right front.  I believe they are the same part.

 

Left rear hook on the front right of the car.  Hook portion should point the other way.  I will need to replace this hook with either the middle of the right one above.

 

Does anyone have fastener specifications (size and grade)?

Thanks,

Keith