Jack:
Been watching this one - my feeling is that there is something else not
right, either a problem in the BJ8 distributor itself, or a possible fuel
delivery problem. The difference in cam grind between the MKII cam and the
MKIII cam would not be enough to account for what is happening - in fact,
most people seem to regrind the MKII cam to BJ8 specs without problems -
that's what's in my tri-carb.
You might try removing the Pertronics and sticking a set of points and a
condenser in to rule out a problem with the module (although those things
tend to be either an 'on' or 'off' situation.)
One sure way to tell would be to re-install the DM6 distributor without
making any other changes (yeah, I know, it's a pain) and see what happens,
then go from there. It goes without saying that the basics should be
checked first - wiring, vacuum advance diaphragm, carb needles and settings,
fuel flow, possible blocked fuel filter, etc. etc. in order to avoid
unnecessary work, which I'm sure that you've already done - I know of
several earlier cars running BJ8 distributors without problems. I'd stay
with the factory recommended basic timing setting - you can always fool with
that after the problem reveals itself and the car is running well.
Good luck - keep us posted.
Earl Kagna
Victoria, B.C.
BT7 tri-carb
BJ8
- Original Message -----
From: "Brashear, Jack, N" <JNBrashear@garverengineers.com>
To: "Michael Salter" <msalter@precisionsportscar.com>; <Warthodson@aol.com>;
<healeys@autox.team.net>
Sent: Tuesday, June 12, 2007 12:53 PM
Subject: RE: Ignition timing - another question or two
Hi Michael and All, it's hair pulling time for me. Here's what I have
right now: a newly rebuilt to stock BT7 Mk2 engine (29E) but using a
BJ8 distributor with neg. ground Pertronix. Yes, I changed up the drive
gear and got rid of the mechanical tach drive unit to install the 25D (I
think) distributor. The car starts easily and runs very well at idle
and low-ish rpm. However, when I try to accelerate, the car feels like
it being pulled back by bungie straps...very lethargic and reluctant to
move out. I've tried about every timing setting I can think of with not
much change in performance. The dist rotor points approx. toward the
front of the engine and the cap, wires and dist are in their normal
positions. My question is...is the BJ8 dist a bad choice for the BT7
Mk2 engine?? I feel the cam grinds are probably different...maybe the
different dists make a bigger difference than I had imagined...?? I
still have the original dist and apparatus...should I return to the
stock distributor?? Somebody please help..!!
Jack
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