Bob,
You are very industrious!
Your timing numbers just don't make sense sense and I have to ask just to
make sure that you do not have a timing tape for a balancer that is smaller
than the one you are actually running as this could explain the funny
numbers. IE: smaller Balancer Tape would read up advance faster thn a larger
diameter one...just a thought. failing that just confirm that the timing
tape is accurate at 40 degrees. You could use the formula to determine how
long the tape should be from 0 to 40 degrees based on the diameter of the
pulley. I can't say that the formula is on the tip of my tongue and I don't
want to go look it up but one of the rocket guys probably recite them in
their sleep.
So if you are going to do this here is the plan forget drivability as with
10 degrees initial it will have the throttle response of a slug but what is
really important is what it is doing at around 6000 RPM. I hope that the
chassis dyno can correlate HP readings with RPM because what you need to do
is only do readings from 4000- 6500 as the low end initial is too low and
the curve will be messedup. Start at about 35 degrees total at 5000 ( you
can use 400 as long as you are positive that the timing doesn't creep up at
higher RPMs I know that ou HEI was good for 1.5 degrees between 6000-7000)
Do run afetr run recording horsepower for the range 4000-6500 under load.
Each time increment up the timing by one degree until you see horse power
drop. Be sure to run the gas you normally run so that it will emulate the
street situation. after you determine the Total that is the best for the
engine the go get the distributor recurved to provide the correct amount of
advance "in the distributor" when you set the initial to 16 degrees and the
total to the number that you will find after your tests. Your engine may not
decrease in horsepower as you add advance but if it is flat HP go back to
the lowest timing setting that gave you the highest HP. Be sure to index the
plugs!<snipe>
let me know how it goes!
Regards,
Tim Ronak
----- Original Message -----
From: Bob Palmer <rpalmer@ames.ucsd.edu>
To: Tim Ronak <timinvan@fox.nstn.ca>; Tiger News Group Address
<tigers@autox.team.net>
Sent: Friday, June 04, 1999 5:55 PM
Subject: Re: Fw: Bob palmer sparkplug fiasco
> Tim, et Listers,
>
> OK Tim, I just bought a Sears timing light with the knob for measuring
> advance relative to the TDC mark. I get about the same numbers I was
> getting with other lights using the timing tape. At slow idle, about 500
> rpm, it has 15 degrees advance. At 3,000 rpm it is 42.5 degrees and at
> 4,000 it is full in at 45 degrees advance. I have been driving it this way
> for about six weeks now, which is about where I have been running it for
> most of the motor's life, except for the brief episode that I think is
> responsible for burning up the two plugs; that happened just before I
reset
> it back to where it is now, and is what I have come to consider "normal".
I
> had a chance to run the motor full bore just yesterday and I have the
> impression (and a very scary one it is) that it is about as good as it can
> be just as it sits. However, in the interests of science, I have set the
> timing back five degrees; i.e., 10 degrees initial, which will give me 40
> degrees total advance at 4,000. I will use my poor man's chassis dyno to
> see if I think this is any better or worse, and how it runs generally over
> the rpm range and get back to you.
>
> TTFN,
>
> Bob
>
>
>
> At 12:18 PM 6/3/99 -0600, Tim Ronak wrote:
>
> >----- Original Message -----
> >From: Tim Ronak
> >To: Bob Palmer
> >Sent: Wednesday, June 02, 1999 8:15 AM
> >Subject: Re: Bob palmer sparkplug fiasco
> >
> >
> >Robert,
> >I have seen enough to know that I have not seen it all and it may be that
> >your engine might like a little extra timing but my gut feeling is that
> >there is way too much total timing.
>
> snip, snip, snip, . . . .
>
>
>
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