Wayne,
I think the problem is "twin Weber DGV carbs on a modified BJ-8 manifold"
Two single choke DGV's are a million miles away from 3 x twin choke 45mm
webers. And about half a million miles away from 2 x 2inch SUs.
Aren't DGVs a relatively small choke carb - 34 or 36mm? So you've got - what
2 chokes - each around 34 mm or 36mm - each choke feeding 3 ports (on a BJ8
mainifold)? and DGVs aren't a performance carb anyway.
So lets get this straight. A STANDARD BJ8 has a pair of 2 inch SU's. Thats 2
x 2 inch chokes (i.e. each choke is just over 50mm).
This car has 2 x 34mm (I think DGVs are only 34 or 35mm chokes?) - thats
roughly equivelent to 2 x 1 3/8 in chokes - either way - much less than a
1.5in (38mm) choke
So the engine has less carburation than it would have with 2 x 1.5in SUs -
and I used to run 2 x 1.5in SUs on my Bugeye Sprite!
Put on 2 x 2in SUs.
Best
Chris
www.myaustinhealey.com
----- Original Message -----
From: "WAS" <Waschu2@charter.net>
To: <healeys@autox.team.net>
Sent: Tuesday, July 19, 2005 4:18 AM
Subject: Cam timing
> Hello,
>
>
> I need to get another opinion about a friends Healey. Rebuilt 2639 cc
> .030" oversize engine, BJ-8 camshaft, Mallery distributor with electronic
> ignition. The engine is not producing anywhere near the power it should.
> It idles well, runs smooth, but is way down on power. It has none of the
> low end torque or high end power that it should. Another variable is the
> car has twin Weber DGV carbs on a modified BJ-8 manifold done by Pierce
> injection. The setup is similar to the goose neck setup for TR-6's.
> Measured the total ignition advance at 3000 rpm and got 35 degrees which
> seemed close enough. Checked the cam timing per Norman Nock and his Tech
> Talk, set a wide running clearance, .095" in my case, on valves 11 and 12.
> Set # 1 cylinder on TDC and measured the clearances on 11 and 12. Should
> be the same clearance, in my case they are not. # 1 intake had .010" and
> the exhaust had .057" clearance. I backed up the crank and turned it in
> the direction of rotation until #11 and #12 valves had the same clearance
> and they were the same at 6 degrees BTDC. Total lift at the valves was
> measured at .360", very close to BJ-8 specs. Measured the opening of the
> intake and closing of the exhaust and with .012" clearance at the rockers
> the intake opens at 26 degrees (10 degrees early) and the exhaust closes
> at 11 degrees (10 degrees early).
>
> I would like to degree the cam but due to an after market crank damper I
> cannot fit my degree wheel without pulling the radiator and lifting the
> engine off of the mounts.
>
> Norms test seems to indicate that the cam is advanced about 6 degrees,
> my test agrees with the cam being advanced about 10 degrees.
> My guess is the cam being advanced while not good does not explain the
> lack of power.
>
> When I pulled the spark plugs they look very lean even at idle so I
> suspect the problem is a very lean mixture across the whole rpm range. Is
> anyone else out there running two Weber DGV carburetors?
> I told my friend if it were my car I would remove the Webers and put on a
> pair of HD-8's.
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