Randalla

Thanks Zed Head for your thoughts and link to the excellent tutorial. I learned a few things I wasn't aware of. Pretty sure my E-88 came from a 49-state 240Z, so likely fairly small combustion chambers, if I'm following you correctly. Car does run exceptionally well, so small gain with high cost is not really on the table. I had the option of installing flat-top pistons when I installed the re-worked head. My desire to get the car back on the road trumped the piston swap. This post was spurred for the most part by curiosity over what my impatience may have cost me. I may still swap on my Webers, though, I've had my triples on one of my other 240's and, honestly, my experience has been well set-up SUs perform just as well on the street, with a lot less headaches. Thoughts?

No, I haven't measured cylinder pressures. I know compression numbers are different, but for what it's worth, compression when checked a month ago was: #1- 160 psi #2- 150 psi #3- 150 psi #4- 150 psi #5- 150 psi #6- 152 psi

Thank you for your thoughts. A bit more info on the head/engine, the stage II cam specs are 480 lift and 276 duration. Good question about which E88 head I've got. Absent removing the head, I don't think there's any way to confirm that.

I have a freshly built, SU carbureted, L-28 in my 72 240Z, with about 5,000 miles on the rebuild. The bottom end is a 280ZX block with stock dished (turbo) pistons. The head is an E-88 which has some port matching done, and the valves have been unshrouded. I'm running a stage II cam with total timing set at 34-36 degrees. I run a stock cast iron exhaust manifold connected to 2-1/2" pipes running through a glass pack type muffler. I ran a pair of "SB" profile needles in my SUs for a couple of dyno pulls to assess where I'm at. My goal was to build a very street-able engine, without having to worry about detonation. Of course, now I'm looking at potentially bumping power with some additional mods. The best current dyno run, at the wheels, produced 180.1 horsepower and 224.5 foot pounds of torque. My question is, "hypothetically," how would swapping out dished pistons for flat ones likely impact those numbers. The downside of course is that I may not be able to run as much total timing without detonation and potential risk to my engine. As an aside, I also have a nice triple Weber set up I'm toying with the idea of swapping on. I realize this exercise is pure speculation, but would be interested in any feedback. Thanks!

May be interested in your 4 screw carbs if they are still available.

I've sent multiple messages but never heard from you. My email is rlewis1957@cox.net. I can PayPal funds immediately. Phone number is 602-312-4038. Thank you. Randy

I'll take these if they are still available and complete as they appear to be.

Looks like I'm going to be a busy boy tomorrow. I should have said that the first thing I checked were the two fuses, which appeared to be fine. I know, looks can be deceiving, so tomorrow I'll switch them both out with new, just to be sure, before pursuing the other avenues. Will also "hose" down the dimmer switch as that's also an easy check. Steve, thank you for your suggestions and reminders as well. With any luck, I'll report back with positive results tomorrow. Thanks again guys!

Thanks guys for the quick response and thank you Chuck for the very through explanation. You've given me an excellent place to start. With this crazy Covid, I've got nothing but time. Very much appreciate the advice!

I have a 72 240Z that has a screwed up combo switch. Need to determine if it's fixable or if I need to replace it. Blinkers work fine, left and right and front and back. I have no headlights at all on low beam. On high beam, I have a bright passenger side light and a dim driver's side light. Guidance on where to start would be much appreciated.

Thanks for your order Steve. I just dropped it in the mail.

If anyone's still interested in purchasing a Float-Sync, I have just 20 sets left. 30 have been sold since April. Not sure yet if I'll produce additional units or not. They're available on eBay.

siteunseen's approach is a good way to more precisely check float levels. I manufacture and sell Float-Sync on eBay (pictured below) and have received excellent feedback, if you are interested. Float-Sync is the best way to calibrate float levels between two Datsun 240Z SU carburetors because you'll actually be able to see the fuel level in each bowl, even with the car running. The level of fuel in the float bowls is the first step you should take before making other fine adjustments to optimize “runability,” In my experience Float-Sync gets you to the baseline as quickly and accurately as possible. I learned, like most of us, to set float levels by removing the float bowl cover and measure the distance between the edge of the lid and the top of the float while the cover is inverted. What I've since learned is just how imprecise this approach is because many variables. Those variables include whether the carbs are being run with or without float bowl gaskets, how many turns down the jet nozzles are set, if the float valve is fully opening and closing, if the float bowl lid has short or long ears and if floats are intact and their buoyancy is the same in each float bowl. I'm sure there are a number of others.

Any way of knowing which of the two side switches might be causing the short? Not really sure I understand how the circuit works, given there are two very similar switch boxes, one on either side of the stalk. Any idea how the two function together? Is one for low and park and one for high beam?

Thank you Zs-ondabrain, this is exactly what I needed! Back to work now.

I ran into a similar problem recently on a car I purchased. Make sure none of your fuel hoses are too big for the metal lines they connect to. If they're not the proper size, it doesn't matter how tight you make the hose clamps you will not get good enough suction to fill your float bowls. They should be hard to push on. If they are not there is a pretty good chance they are too large a diameter.

Series I 1971

I got brave today and took my headlight switch apart to clean up the contacts, as the switch was working sporadically. Everything went great till I realized I had an extra part left once it was all put back together. The part is a very small plastic bushing that apparently keeps metal parts from shorting against each other. I believe there is a total of 3 of these in the whole mechanism. I have no question where two of them go (they hold down and isolate the two headlight switches from the contact for the wiper washer. I guess the third one fell out when I was disassembling it and I did not see where it came from. Now when I flip the switch I blow the 20 amp fuse, so there are definitely two things touching each other that shouldn't be. Pictures of the bushing are below. Can anyone tell me with where the lone one is supposed to go? Thank you in advance!

I've had them apart and they didn't look like any Z buckets I'd seen before. Without the spring and the tabs to attach it to, it sure looks like these are not the right parts.

I'm afraid the previous owner may have substituted parts from something else.

Wouldn't you know it, I just had the center console out for something else and got it all back together. Thanks for the advice guys. I guess I'll repeat the process, Arghhh!

Recently acquired a series I car where the glass lenses for the fuel and oil pressure gauges are so loose that they ratter and lay against the needles so the gauges don't read properly. I want to get them out of the IP to repair, hopefully without pulling the IP or coming in from the passenger side through the glove box and destroying my glove box liner. Is it possible?

I have a set of headlight buckets on my series I 240Z, that does not have the spring or tab inside for adjustment like my series II 240Z. Are they different or do I have a set of buckets in my series I car from something else? Not sure there is any way to adjust the light on my series I car currently.

I like your idea siteunseen. A little worried the next time I need to take the taillight apart I may have the same issue, given the extra resistance typical with loosening up a nyloc nut.Think I'll try using the old hardware and just add a small flat washer to make sure the nut does not pull through the plastic housing.

Thanks for the reply Peter. Actually there are small captive acorn nuts that the Philips screws screw into. They're held in place by the plastic molded around it. Once the bond is broken, it just spins in the plastic housing. The only way I could see to get the taillight off was to carefully carve away the plastic around the nut enough to get a vice grip or wrench on it. Finally got it off. I'll need a washer along with the acorn nut and screw to secure it back together upon re-assembly.