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[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] Re: head machining
>
>By the way, I have a problem with idle that my dealer said was a result of
>the PO having the heads machined (un-equal cylinder compression?). Has
Since you said "heads", I have to assume a V-12. I'm very curious about
how the dealer arrived at this conclusion. the implication here is one
head was machined a lot more than the other, raising the compression on
that bank. How can they tell, and if this is the case, how would it effect
the idle? The V-12 operates as two six cylinder engines intertwined. You
could totally shut down one bank, reset the idle speed, and the engine
will idle well.
If there was a mistake during head work that would have an effect on
the idle, the most likely point would be cam timing.
BTW, with the Mays head design, you would have to mill a very large
amount off the bottom to have an impact on the compression.
>anyone had any experience with the Ultra Team ignition system from Jacobs
>Electronics. They claim to cure (among a list of other things) erratic idle
>while increasing mpg. Is this worth investigating?
Modern cars (80-90's) have a sufficient ignition system to prevent misfire.
they have to in order to meet smog requirements. There is *very* little
to be gained by upgrading to a hotter spark or multi-spark ignition, if
the rest of the engine is untouched and operating under normal street
conditions.
I have used Accel, MSD, and Electromotive ignitions on hot street and race
engines. On the street engines, there really isn't much improvement until
you get into really high RPMs. I have never used Jacobs equipment simply
because I have been totally unimpressed with their techno-babble hype
passed off as an engineering desertation.
>
>Mark Revels
Randy K. Wilson
randy@taylor.infi.net
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