Ok hers the deal.got a 240z with a l28 motor.it ran pretty good when i got it but way to rich.so bad i couldnt stand the smell...so...i bought a ste syncronizer and a color tune.i have the carbs. Pretty close now...they were way out of sync.only thing is it runs like crap know..seems to be popping alot through the exhaust.and stalling out on take off.the front carb fuel adjustment had to be turned all the way up to get the color tune blue..and i will also say it was hard to get them both in sync. At an accceptabal idle..actualy i couldnt even use the idle screws on the linkage because it would idle to fast...are the carbs sopposed to open at the exact same time.because the front one had about a 1/4 inch lag from the back carb.so i bent the lever to make up the differance.i know some of the vacum parts that mount on the top,have been taken off.and from the photos that i have seen,it looks to me like that front carb,had some linage hooked to the vacum parts.i was thinking about doing a carb.over haul..hope this all makes sense to you all who read it.feel kinda stumped here hope you can help..

Not to undermine the extent of your problem, but it is imperative that you begin to educate yourself on the workings of these nearly forty year old cars before aimlessly turning screws, bending levers and hoping for a miracle. the SU carb is for the most part a very simple mechanical device that when properly tuned will give years of reliable performance with little attention.

Start with the basics by knowing which model SU your L28 is equipped with; round top, flat top, 3 screw, 4 screw. You may want to download the factory service manuals for the vehicles that came with SU's (70-73 240's) here http://www.xenons30.com/reference.html, and/or use the search function at this site. There is a wealth of information here for you to learn from.

Lastly, your post is extremely hard to read. This is not a site to use texting shortcuts with an expectation of quick results. Proper punctuation and use of a spell check will go a long way toward better response. That said, I wish you the best on your goal of restoring your Z.

After talking SUs to people all day at Canby today I'm out of ammo for an internet diagnostic other than to say order the JUST SUs DVD and start through them.

The search feature on this site works great with many excellent tidbits within all the conversations.

Welcome to the site!

Thanks for the info Spotty.I will try and be more delineated.And thanks for the website.It will be very useful................................................Matt