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Twin Webers too much

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Basil

Basil

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I think I have decided that the Twin Weber 40's on my Spitfire are too much carb for that car (at least as a street driver). I have decided to convert to a single Weber. I have a hot street cam, but even with that I think the twin Webers are just to much for that car. Anyone know where I might find a manifold for a single Weber DCOE 40 on a 78 Spitfire?

Also, Does anyone have a good idea of what size choke, and jets I should use with a single DCOE carb on a Spitfire (at 6000 feet)?

Basil

[ 05-01-2004: Message edited by: Basil ]</p>
 
You might possibly get the duals to work by going to 24mm main venturis with the associated jetting. I think you are right though, a single is easier to setup & less carb parts to buy. You would also have a better place to connect the vacuum advance. I don't know where is the best place to get a manifold. I'm sure that someone will know.

Probably something close to the following would work:
main venturi - 28
aux. venturi – 4.5
main jet – 110
emulsion tube – F16
air corrector jet – 160
idle jet – 45F9
accelerator pump jet – 50

A main jet somewhere between 105 & 115 should work at your altitude.

Just out of curiosity, what are the specs on your present carbs?
D
 
Here's a source for the Cannon manifold that will fit your car (four port)...looks like it's $118. Cannon may also sell direct...I didn't look for their website:

https://www.jameng.com/prices/index.phtml#99003.804

For what it's worth, I agree about that setup being a bit too much. I'm running a single one barrel carb (2" S&S) on my 1500 and it's plenty, even for racing. Previously I was running a single HS-4 SU adapted to the stock maifold with a simple adapter plate...that was actually pretty decent too.
The twin Webers look great: that's the only thing compelling about them, as I see it.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by aeronca65t:
Here's a source for the Cannon manifold that will fit your car (four port)...looks like it's $118. Cannon may also sell direct...I didn't look for their website:

https://www.jameng.com/prices/index.phtml#99003.804

<snip> The twin Webers look great: that's the only thing compelling about them, as I see it.<hr></blockquote>

Thanks for the link, I'll check it out. You're right, they look cool, but way more trouble than they're worth. Think I'm gonna sell one carb and the twin carb manifold and go with a single.

Dave - thanks for the set up info. Gotta start somewhere.

Basil
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by MDCanaday:
My vote is to sell BOTH the webers and go back to twin SU's, Nothing like the classic look!!!!
MD(mad dog)<hr></blockquote>

My car originally had Zeinth, and I'll NEVER go back to those! Twin SUs would be nice, but I have to work with what I have.
Basil
 
More Power!! 4 webers. One for each cylinder.
crazy.gif
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The single Cannon intakes show up on ebay from time to time. Some people say its not a great setup but I don't know from personal experience. Seems to me it would be OK.

John Kipping (on spitfire-enthusiasts.yahoo.com)
says a single SU H-6 on an intake from some Triumph we didn't get over here (US) works great. I think it was Toledo or something. He says it has bigger passages and flows better. Plus it has better low range torque.
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by Bruce Bowker:
More Power!! 4 webers. One for each cylinder.
crazy.gif
grin.gif
<hr></blockquote>

some people use 4 bike carbs ...

mcginnisenginebay.jpg
 
WOW!!!!! Love it!!!!
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by 78Z:
[QB]

some people use 4 bike carbs ...

<hr></blockquote>

Wow, that is cool! What type of carbs are those?
Basil
 
<blockquote><font size="1" face="Verdana, Arial">quote:</font><hr>Originally posted by 78Z:


some people use 4 bike carbs ...

mcginnisenginebay.jpg
<hr></blockquote>

Does the bike now have twin SU's?
grin.gif
 
Bike carbs look cool, air cleaners would be a nice addition.
 
Bas,

If you want twin SU's I may be able to get you a couple I have several laying around and I kow a guy who literally has boxes full of them.

Cheers,
thirsty.gif
driving.gif

Walter
 
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