Triple Mikuni Tuning Manual?

[shankeroid]

Just acquired a 260z with triple Mikuni 40PHH's and would like to learn proper tuning techniques for these carbs.  I've done numerous searches for any kind of manuals dealing with the subject,
and the only one I've found is the "Mikuni PHH Carburetor Service Manual."

Anyone have any leads on any other manuals that deal specifically with tuning these carbs?

[madkaw]

Might read this thread - might help

https://www.classiczcars.com/forums/topic/42960-triple-mikuni-thread/

[duffymahoney]

Here is the original.Pm I can send you one, that I would rather not share.  

 

http://www.tuning4performance.com/documents/Mikuni -44-PHH-SM.pdf

 

 

[shankeroid]

Thanks, Madkaw and DM.......a lot of threads to sift through!!  I do have Mikiuni's PHH Carb Service Manual, but looking for a manual or guide (if one exists) that can start me from the beginning at step one.  I know the process is a lot of trial-and-error, but where to begin?  This is all new to me, but I have the time and patience to learn.

[240260280]

Not Mikunis but close enough that you may pick up some helpful data:

http://240260280.com/Tech/Carbs/Weber/DCOE Theory Operation and Tuning.html

[Mike]

From what I've seen, tuning Mikuni's is a 'process' of its own.  When I had mine installed, the guys at Ztherapy had to play around a bit with jet sizes to get them to work correctly.  Steve had a small kit (with different jet sizes) and was experimenting until it was tuned properly.  My car has a mild cam upgrade and a L28 block.  He was able to tune it to work with my driving style.  Results will vary depending on what you want to do with the car.  If it's a daily driver, you'll use one set.  But, if you are racing track, there will be a different set.  I don't know where to get the different jets, or even a kit, but, it may be worth a call to someone experienced with the carbs.

That said, after the main tune up, I haven't had to touch the carbs since.

[Mike]

I did find this website with more information about recommended jetting.  It does have recommendations for 240z-280zx.

https://www.upgrademotoring.com/performance/mikuni/mikuni_jettingparts.htm

 

[shankeroid]

Excellent, Mike. Grassy-arse!

[240260280]

Interesting:

240/260Z/280Z have same Mikuni Settings for 40mm's.

Weber and Mikuni are close for same choke:

 

 

[madkaw]

Buy a wideband O2 sensor and install - it will make life much easier for you