I definitely agree with you, Paul. When I mounted the Cannon intake manifold, I
did not have to make any "adjustments" to the exhaust manifold. I do have the
same tabs and mounting flange on the exhaust manifold that you describe.
...still waiting to hear some real measurements of the listers intake manifold
offset. Their input will be really helpful in putting this to rest.
Vic Whitmore
wizardz wrote:
>
> Well in looking back through various materials (web, printed, jotted notes)
> I think the root of this manifold problem is due to the variations in exhaust
> manifolds fitted on various models.
>
> I've now seen three different exhaust manifold variations, each with slightly
>different
> clearances and various other protruding tabs and flanges.
>
> I can only surmise...they made a variety of intake manifolds due to clearance
>issues.
>
> Even in the installation viewable in the photos of my DGV mounted on the '80
>spit,
> http://www.teglerizer.com/triumphstuff/bs_engine.htm I had to grind a tiny
>bit off the
> two little ears that stuck off the exhaust manifold to get proper clearance.
> In comparing the exhaust manifold presently on my '75 (EGR valve on the side
> of the manifold under the carb) the shape of the exit from the block is
> different from the spare manifold I have (where the ERG valve mounts on top
> the exhaust manifold)
>
> Maybe when looking for an intake... a variation in which model year engine
>it's
> being fitted to is needed.
>
> Paul Tegler wizardz@toad.net http://www.teglerizer.com
>
> ----- Original Message -----
> From: "Vic Whitmore" <vicwhit@home.com>
> To: "Spitfires Maillist" <spitfires@autox.team.net>
> Sent: Friday, August 25, 2000 3:30 PM
> Subject: Weber DGV Help - Part 2
>
> The response to my original plea was very helpful and I thank you one and all.
>
> The net result seems to be the offset in the manifold. The manifold must drop
> downward so the the carb can sit low enough to clear the hood. As several
>people
> have pointed out, the problem is known, if not common, as you have seen hoods
> with outward dents where the air filter has hit the hood. But many other
>people
> have had no problems.
>
> At first I thought it may be the Cannon manifold I have. Paul Tegler, for
> example, used the Pierce manifold that appears to have more offset than the
> Cannon. But others have reported successful installations using Cannon. I then
> contacted Pierce for a replacement manifold and learned that indeed the Pierce
> has more offset, by about 1/4". I don't think that is enough. It looks like I
> need about another 3/4" to safely clear the air filter. At the very minimum,
> maybe 1/2" would do it.
>
> So there appears to be some other factor at play here. As someone mentioned,
> motor mounts may be a factor by raising the engine higher than others. Maybe
>the
> hood position is a factor but mine is very typical as compared to other Spits
>I
> know.
>
> But I'm not giving up on a possible difference in manifold offset. If you
>could
> measure the offset of your manifold, the make, and model number of the
>manifold,
> it could help to confirm whether this is a factor. I need to know how much the
> top of the tubes drop from the engine end of the manifold to the carb end, as
> measure on the tube not the mounting flanges. The make/model may be on the
> manifold casting (mine says Cannon and a four digit number).
>
> Even better, if you have solved this problem, I would love (as would many
>others
> with dented hoods) to hear your solution.
>
> Vic Whitmore
> 76 Spitfire
> Thornhill, Ontario
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