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I've been working on a new product for the last six months that I'd love to get some feedback on. I've always known getting the floats in SU's set properly, and knowing for sure they were set the same in both carbs was important, but the method of doing so always seemed imprecise and less than elegant. I developed Float-Sync to know precisely where floats were set and have a visual reference, without removing the float bowl lids. On three screw SU's, there's a threaded plug in the float bowl that can be easily removed to substitute Float-Sync. The level of fuel in the float bowl dictates the level of fuel in the jet nozzle. This is a big deal for SU carburetors because the fuel level in the jet nozzle directly impacts engine performance. When the engine is running, a vacuum is created in the SU carburetor venturi that pulls fuel out of the jet nozzle, mixing it with air and drawing it into the engine. If float levels are adjusted too high, fuel puddles at the top of the jet, allowing too much to be drawn into the engine, creating a rich condition. If the float is adjusted too low, it's harder to pull fuel out of the jet, creating a lean condition. A rich condition can cause plug fouling, poor fuel economy, gas fumes, diluted crankcase oil (contributing to blow by and reduced engine protection), and in extreme cases potential for an engine fire. A lean condition can cause the engine to stumble, back-fire, ping and run hotter than it should, creating the potential to burn valves. Float-Sync allows you to see precisely where your floats are. You can see the fuel level, with the engine running, throughout the entire RPM range… all without opening the float bowls. You will never wonder again if your floats are adjusted correctly. I'd be interested in your feedback and suggestions. I listed a few sets for sale on eBay yesterday to gauge interest. Thanks

I have several questions regarding the precise fuel pressure both of the 3 screws round SU CARBS on my 240z will tolerate as i am pushing the fuel through an AIRTEX 8012S which is rated 5 to 9 PSI: 1. Should i measure the fuel pressure plugging a "T" before the front carburetor? 2. Should the pressure read no more tan 4.3 psi? 3. What if the pressure reads more than this limit but does not show any spill out of the fuel bowls? Will i need to open both fuel bowls and reset the level. THis was done by Ztherapy in 2014 and i would not like to mess with it.

1972 240Z, automatic, with aftermarket AC. ISSUE: Between approx. 1100 to 1800 rpm when the motor is at operating temp., the engine will; cough, sputter, miss through the back/rear carb and it makes it hard to leave stop signs. As soon as it hits 1900 to 2k rpm it takes off like crazy and runs perfect. it is a fast car for what it is. This is my fourth Z but my first three were brand spanking new with no troubles except for my 74 260 that hated cold weather in South Dakota. I also had a 71 240Z, automatic and a 76 280Z 5 speed, all back in the 70s new. I got this Datsun 240Z in November 2016. I have had this trouble all along only so much worse I when I got it, I could not drive it anywhere for fear of dying. So here is what I have done; PARTS: new plugs, new rotor, new, distributor cap, new dual points, new condensers, new plug wires, new ignition coil, new mechanical fuel pump, new air cleaner filter. Put oil in the top of the dash pots. I took it to a mechanic who said he used to work on them years ago and raced datsuns. He said he pulled the distributor checked it all out, set carbs and timing and and put in new plugs, and reset the points gap, and said one of my new condensers was bad so he replaced it, and did whatever for 300 bucks, it ran great for one day then started doing it again the next day. Took it back and paid him 80 bucks more for whatever he did, got home 30+ miles away and it started doing it all over again. He said come back and I haven't because; it used to cough through the carb so hard it would fall flat on its face and sputter in the back carb, and keep doing it so that it was almost dying until I hit the 2k rpm. Then I did all the work I said and it seems the added oil in the carbs brought it to a milder miss/ backfire or cough thru the rear carb. It runs so much better now at the low rpm but it is still there. When it is a cold engine start, I choke it and it starts up, sputtering a lot and i right away ease up on the choke. it coughs thru the rear carb giving it gas in park at the low end until it warms up, After engine warms up, it only misses or coughs through the rear carb when the car is in drive under load or reverse. Park or N it runs great at low rpm on up to any rpm. It sounds super and runs super. CHRIS, Florida 19,500 OBO tired of dealing with it and don't have an easy time getting in and out of it. I am old and too heavy, But I love these Z cars.

Trying to complete my labor of love and bring a father/daughter project back to life on a 1972 240 z original persimmon and white interior. This started as a father daughter project and life and poor health got in the way! I'm back on the case and have finished the mechanics, just trying to complete the last of the bits and pieces. Would love to drive up to my dads house with her purring and beautiful! I have monitored all the regular sites, and either can't find, they are in poor shape, or are too expensive! (I'm already way over budget!) So, I'm hoping some fellow members may have some of these needed parts they are ready to "part" with at a reasonable price. (No pun intended!) The below parts needed: 1) Left front blinker full assembly (need lens in good shape) 2) a/c control unit (interior) I have the functioning A/C unit, but would love the controls that mounts to left of the upper left console by the gear shift. 3) 240 horn pad and/ or the spring and mechanism behind it. 4) rubber grommets around inside of engine compartment, same for those inside the lower rear hatch ( mine are really dried out) 5) choke handle ( interior) *** FOUND! Thanks to Grannyknot 6) 1972 chrome wheels and/ or tires in good condition 7) Original SU carbs by chance? 8) White interior pieces ( rear area and the antenna access area... Don't want new, too white!) 9) rear hatch strut? Mine is ok, but kinda weak. 10) rear hatch louvers ( the no drill kind) 11) Antenna motor-working (mast not needed) i think that's it for now. If you happen to have any of these items please let me know. i will check off and/or update this list as parts are found. I will also add any parts that may be needed as I finish my restoration, so please check back Ok my fellow Zer's, can you assist me in finishing this true labor of love! Thanks much for the help in advance! Kira The lil Z lady! you can reach me here or at kirareisch@gmail.com Below is my Z prior to restoration in 2005

Needed SU carbs in good shape at a reasonable price. Can you help? Id appreciate it much! Kira The little Z lady

Yeehaw!! We are in receipt of pre production trial floats and Steve said everything is running out very well. Spread the word and let me know if you or any of your playmates want a pair.

Hi, I was hoping someone could assist me with a drivability issue I've been having. When the car is off, the gas pedal is easy to depress, and entirely normal, however when the car is on, the pedal becomes difficult to press, and if i press too much it will gun it. The car in question is a 73 z, l28, flattop pistons, mild cam, roundtop su's, throttle cable conversion. Thanks for any help, I'm hoping its something dumb and simple. Also, the car is running a little rich as of the moment if that matters (needa tune the carbs)

I swapped out my new su carbs from z therapy for the 73 flat tops. A little confused on the heating hose which comes out of the engine and runs thru the carbs for warming. 1- Is there a sensor placed in this in this line? ( pic shows blue hose from engine to carb metal line). 2-Also , I see engines without the heat shield, do I need to replace? 3- the engine has been overheating in about 15 minutes and the mechanic can't find anything for cause. Thanks, Brian