Advice required 45DCOE for MGB

I'm trying to fit a 45DCOE Weber carb to an MGB. On the manifold supplied there is a take off for the brake servo vacuum hose but nothing for the vacuum advance an retard.

Question is - is the vaccum advance and retard still needed, if so wheres the best place to plumb it in? The local parts shop suggested having a junction on the servo hose which sounds likely as I don't want to make aother tapping into the manifold.

Any suggestions guys?

Mart

Reply to
Mart
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I'm certainly no expert, but from what I've gleaned, a DCOE is wretched overkill for any but the most heavily modified engines. If you haven't matched the flow capacity of the head, cam, and exhaust to that of the new carb, the potential of the carb will be wasted.

That said, I'd expect that if you haven't changed the distributor, then it will still need whatever it needed before the carb switch. You can probably run without vacuum advance, but I would expect the result to be sub-optimal, and for sub-optimal results, why go to the expense of fitting the DCOE?

What year it the car? Did it originally have manifold vacuum to the advance or ported? That will determine how you will need to hook it up on the new rig.

Sorry to not be more optimistic about it! :-(

Reply to
Declan MacLeod

The engine is a 1972 with vacuum advance. Head is a Downton stage 1 with the 'bunch of bananas' MG club stainless exhaust manifold.

Had a note from a chap in California saying don't use the vacuum a/r line. He also sent the address of a good site -

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- that gives tips. Looks like I've a fun time ahead...

Thanks all

Mart "Declan MacLeod" wrote in message news:declan snipped-for-privacy@news2-ge0.southeast.rr.com...

Reply to
Mart

Why? You'll lose a fair chunk of the driveability, 10 mpg and get very little more power. The twin SUs fitted as std are excellent carbs on that application.

Reply to
Dave Baker

Yep

Just looked at the tuning book and at stage 6 - 10.5 CR this is the difference between SU's and a 45DCOE

1 BHP at 3000RPM 6 at 35000 5 at 4000 3 at 4500 5.5 at 5000 4 at 5500 1.5 at 6000 minus 1 at 6500 at the GBox flange
Reply to
Rob

Dave Hi,

Just been looking at your web site, its superb information, but would prefer to see pictures and diags too.

Reply to
Justin Baker

Well so would I. If you're volunteering to create them and rewrite all the web pages I'll be jolly grateful. It's taken hundreds of hours over the years just to write what's already there and much as I'd like it to be better still there are only so many hours in the day.

-- Dave Baker - Puma Race Engines

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Reply to
Dave Baker

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