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Tach bounce fix needed

PostPosted: Sun Jan 16, 2005 5:41 pm
by pamitchell
I know this subject has come up before and I'm looking for additional
info. Experiencing intermittent tach bounce usually over 3000 RPM.
Running Mallory Unilite (optical)dizzy and Mallory coil w. Smith's
RVI tach.
Is there a fix available to wire in a diode or choke to the tach
circuit?

Thanks!
Phil Mitchell - San Jose CA. 69 S4 FHC

Tach bounce fix needed

PostPosted: Sun Jan 16, 2005 7:17 pm
by wgrainge
I believe that people have tried a variety of low-cost fixes with
really mixed results. It's my understanding that the only real fix is
to send your tach away and have the internals converted. I did
this a few months ago. I phoned around and the best price I
found at the time was North Hollywood Speedometer.

http://www.nhspeedometer.com/

I was really pleased with their service. Can't recall the exact cost.
Around $140 to $160.

-Will Grainger
45/9693

"Phil Mitchell" wrote:

over 3000 RPM. Running Mallory Unilite (optical)dizzy and Mallory
coil w. Smith's RVI tach. Is there a fix available to wire in a diode
or choke to the tach circuit?

Tach bounce fix needed

PostPosted: Sun Jan 16, 2005 8:59 pm
by Petter Hval
Take a look at.
Lotuselan.net/publish/bouncing_tach.shtml
Petter


----- Original Message -----
From: "Phil Mitchell" <***@***.***>

Sent: Sunday, January 16, 2005 6:41 PM
Subject: [LotusElan.net] Tach bounce fix needed





I know this subject has come up before and I'm looking for additional
info. Experiencing intermittent tach bounce usually over 3000 RPM.
Running Mallory Unilite (optical)dizzy and Mallory coil w. Smith's
RVI tach.
Is there a fix available to wire in a diode or choke to the tach
circuit?

Thanks!
Phil Mitchell - San Jose CA. 69 S4 FHC















Tach bounce fix needed

PostPosted: Mon Jan 17, 2005 1:43 am
by pamitchell
Thanks for the link.
Has anyone modified their RVI tach on their own? What is needed?
My buddy is an electrical engineer so we're up for doing the mods
rather than paying.




--- In ***@***.***, "petter hval" <petter.hval@t...>
wrote:


Tach bounce fix needed

PostPosted: Tue Jan 18, 2005 4:39 am
by lgsamson
If your not doing a concours restoration, I would just gut the sucker
and replace the inards with an modern tach drive you could purchase
cheap new from smiths or anybody else, then the only compatiability
issues would be mechanical ie: does it fit in the can, does the needle
shaft fit the old needle, and can you make a mounting plate.
LGS CPL

Phil Mitchell wrote: