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 Posted: 10-28-2005 03:04 am
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Esprit2

 

Joined: 05-01-2005
Location: Minneapolis, Minnesota USA
Posts: 289
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johnhem wrote: Is anyone familiar with this synchronizer and would they recommend it or not? I read Frank Schwatz's post but would rather not deal with JC Whitney if at all possible. Thanks,

John Hemmings



John,

I'm not a big fan of any air-flow meter that mounts in the air intake.   They all influence the very air flow they are trying to measure.   They can't check the normal running condition since they alter the air pressure/ vacuum the instant they are installed.

The best choice is a manometer connected to read manifold pressure immediately behind the throttle butterflies,  and the best,  IMHO,  is the Carbtune II  (2 and 4 tube models available.   Expensive new, but more reasonable slightly used on eBay.UK.co.

The caveat with manometers is you need a vacuum port immediately down stream from the throttle butterflies to connect the manometer to.   Dellortos come with manometer vacuum ports stock.   Strombergs don't.   Weber DCOE's don't (DCOM's are basically later DCOE-clones upgraded to include many Dellorto features...  including manometer vacuum ports).

If you elect to drill & tap a vacuum port, then it should be located as close to the throttle butterfly as practical.   There are some really funky flow patterns,  pressure pulses and reversion waves inside an intake manifold runner.   Tapping the runner down stream won't necessarily tell you what's going on at the carb.  To tune the carb you need to check the pressure right behind the butterfly.

If all of that is more than you are willing to deal with and you're going to buy one of the units pictured no matter what,  then I've had pretty spotty results with the Uni-Syn.   I wouldn't buy another one.

Once you try a manometer,  you'll never go back.

Good luck,

Tim Engel