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I have been having issues with my OER SK 40mm carbs. The problem is very elusive and I have not been able to find the source. I will do my best to describe the problem and I am willing to clarify if needed. I am going to refer to carb(#1) as cylinders 1 and 2. Carbs #1 and #3 are perfectly fine, it is carb #2 that is acting up. I started to sync the carbs, first by disconnecting all the linkages. I managed to balance #1 and #3 using an unisyn tool. However, #2 (cylinders 3 and 4) would be run leaner than the others. I unscrewed the idle mixture screws for #2 a few turns, and it leaned out even more resulting in popping out the carb and a nearly white spark plug. Also the #2 would draw a lot more vacuum than #1 and #3, and I unscrewed the idle speed screw for #2 and #2 still ended up drawing a lot more vacuum. #2 has enough vacuum that when I touch the unisync tool on #2 the engine will nearly die and then fuel spills out and then rpm picks up a lot. However, I got the car to idle smooth enough by tuning by ear and I would hold rpm at 2.5k and 3k and the #2 carb would cough and the exhaust would back fire, checking the plugs (cylinder 3,4) they were even whiter than at idle. Meanwhile the other plugs were a nice brown. This issue has bee driving me mad. Issues list: 1. carb #2 runs lean 2. (all linkages disconnected)(speed screw backed off 100% for #2) carb #2 still draws more vacuum that #1 and #3 3. Carb #2, touched unisycn tool the engine nearly dies, fuel drips out of throat, engine speed rises rapidly 4. #2 meaning cyl3,4 mixture screw(1 turn), nearly white plug, all others are a nice tan 5. #2 mixture screw(2 turns), completely white plug, all others are a nice tan 6. rpms held at 2.5k and 3k carb #2 cough and exhaust back fire 7. rpms held at 2.5k and 3k carb #2 (plugs 3,4) are bone white, all others are a nice brown 8. no binding in the linkages, linkages move very smoothly 9. Sprayed carb cleaner on all joints and seals, no increase in rpm 10. float levels all set to the same factory settings

It's been a while since I've posted back on the forum but I wanted to check back in and show some progress of my 11/70 240z. I bought the car about 3 years ago and have done quite a bit of work on it since. I wanted to build a mostly period correct Japanese influenced race car for street use. It's in it's final stages now and I know it might not be some of the purists cup of tea but I know some of you may enjoy it and some of the rare bits and pieces I've compiled together. A lot of time, effort, money and blood and sweat has gone into it so far. This is how the car started, a mostly stock series 1 car with dealer option seat covers and wheels, blown out struts, unreliably dangerous brakes that probably hadn't been touched since 1970 and a tired L24. Still a beauty but needed quite a bit of work. Not a bad place to begin, but over the past 3 years I've slowly transformed it into what I thought the car should have been from the start. Not all of the pictures reflect the current status of the car but I'll post some more when I can. Interior is complete with Competition Bucket seats, T3 harness bar mount with a quick release extinguisher, Watanabe Falcon Steering wheel, Skyline shift knob, new door panels, Z embroidered carpet, rally clock, and some other bits and pieces including a radio delete panel with an AFR gauge cutoff switch and some switches. Also have a competition mirror in there and some other neat bits like a works bell QR. Exterior has gotten a refresh. I chose to keep the number rounds and get rid of the other vinyl that was on there. Straightened the black line along the door as well. Went with flares, a 432 spoiler, air dam and external oil cooler. Wheels are staggered 16x9.5 255/55/r16 rear and a 16x9 225/50/r16 on T3 coilover suspension. Brakes are totally redone with the silvermine stage 3 front and silvermine stage 4 rear (toyota 4 piston and mustang gt) with classictube stainless brake lines, 280z booster and wilwood 1" with wilwood proportioning valve. (ride height is a little high to help get a jack under the air dam. I also went with the zstory exhaust with the over under 432 style exhaust. Went with fender mirrors and note the sport corner sticker and other little bits and pieces! As for the engine, I swapped in a 3.1L stroker with some datsun competition mikuni phh44's. SK intake manifold with OER linkages, Zstory exhaust, Datsun spirit heat shield, JDM big Nissan Valve cover, mishimoto radiator and a bunch of other goodies both performance and dress up. Again, pictures are a little old but give you a good idea. Car's almost done and back on the road after quite a long time, but will get some better and more updated pictures when it is. Here's a side project of mine at the moment for "the next car": Competition 44's on a FET manifold paired with a Kakimoto 3100 cover and technical garage Ti stacks with some OER linkages.