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Posted by: 930cabman Jun 1 2022, 05:37 PM

A decent 1975 Palma Green came to me last year, from Cali with very little rust and original paint. She was running ok with a single carb. I changed it out to a set of twin 40 IDF Webers and she has not run decent since. The cheapskate in me has considered simply sending Tangerine $400. and getting it right, but ...

I can get a smooth idle at 5 -6 on a snail, but increasing the throttle opening a small amount I cannot get equal air readings from 1-2 to 3-4. Compression ranges from 110 to 125, leakdown ranges from 5%-18%, valve clearances at .006.

The characteristic popping and poor running are the result of this unbalance condition.

thanks in advance

Posted by: Robarabian Jun 1 2022, 06:29 PM

Hi Cabman,

The popping and poor running is likely due to lean condition. Popping for sure. Once you have timing, ignition and valves all proper, then you can tune the carbs. Get them dialed in low and work your way up. There is alot of info on dual carb tuning here and elsewhere. Make sure they are on the idle circuit and the butterflies are closed. Go from there. Do it without any linkage on the carbs. Then attach linkage and sync the linkage. Then work the carbs..

Again, lots of reading to do, but it isnt just being unbalanced...

QUOTE(930cabman @ Jun 1 2022, 04:37 PM)

Posted by: r_towle Jun 1 2022, 07:48 PM

After trying all the x bar linkage..and I know how to tune carbs, I would suggest you call Foley.

BUT, tune as stated above, jet changes may help.
Buy the jet kit, read up and get it perfect.

Only then will you see the slight difference the linkage makes.

Posted by: bbrock Jun 1 2022, 07:54 PM

No question the Tangerine linkage is the best, but I've been really happy with the CSP linkage which is reasonably priced. Well, as happy as I'll ever be with anything carb related. Will be going back to FI soon.

Posted by: 914werke Jun 1 2022, 08:17 PM

Ive been using a CSP on anything Im "forced" to apply carbs to.

Posted by: 930cabman Jun 2 2022, 04:58 AM

Thanks for the replies. Spark timing is good, idle speed screws are about 3/4 turn in, mixture screws are about 1 - 1 1/2 turn out. It seems as though the carbs are not being activated at the same rate. I have a CSP setup, but mistakenly ordered assembly that works with a 911 style fan. I may send it back or put it up for sale here.

Tangerine will be my first call today.

I have a pile of FI (both D and L jet) stuff laying around, it may be smart to inventory the stuff and give it a try.

Posted by: Superhawk996 Jun 2 2022, 11:56 AM

QUOTE(930cabman @ Jun 2 2022, 06:58 AM)

Posted by: 930cabman Jun 2 2022, 05:38 PM

QUOTE(r_towle @ Jun 1 2022, 07:48 PM)