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Re: [Fot] Low voltage miss?

To: fot@autox.team.net
Subject: Re: [Fot] Low voltage miss?
From: Jim Norlin <norlinengineering@comcast.net>
Date: Sat, 11 Jun 2011 13:52:03 -0700
Scott

I've got the same engine/distributor setup.  However, I'm running an A-8 
cam, so my power peak is around 7000 where I shift.  I can and have run 
the engine to 7500 on a really long straight and the chassis dyno with 
no misfire.  I do not run an alternator.  The battery voltage can run as 
low as 11.0 if I have not charged the battery for a couple of sessions - 
again, no miss.

I do believe your alternator/voltage regulator may be faulty.  
Alternator output should be 13.8 to 14.2 volts from my experience.

Not sure if this helps.

Jim

On 6/11/2011 12:31 PM, Barr, Scott wrote:
> I'm currently using a distributor with a Pertronix II Ignitor in it.  A
> couple of weekends ago at Blackhawk Farms, the engine developed a miss
> at 7,000 revs -  wouldn't pull beyond 7,000.  This is a Spitfire 1296
> small-journal motor with Kas' A-10-A cam in it, so I could use some revs
> beyond 7,000.
>
>
>
> The battery voltage was low all day - something in the neighborhood of
> 12 volts.  Would voltage at that level cause a Pertronix not to work
> properly?  Seems to me that should be enough volts to make it work fine.
>
>
> The alternator seemed to be putting out plenty of charge, but the
> battery didn't seem to improve through the day.  That was the first race
> of the year, so I've pulled the battery and given it a full charge off
> the charger.  Will see how well that works out, but may need a new
> battery, too.  This one's 4 years old now.
>
>
>
> If that doesn't help, I'll have to send my distributor off for testing.



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