Quad DCOE 40s

I'm looking at a cross over quad Weber set up for my Buick 215. It's basicly the same as the Olds Traco engine used in the original Mclaren M1a. Has anyone used this set up? I was wondering about any problems with keeping 4 carbs all in sinc & tuning. I've never had a multiple carb set up just good old 4 barrels. Except the twin set up on my son's bug (we went back to a single LOL)
 
Keeping webers in sync really comes down to how good a job you make of building linkages etc. Carbs will be 45DCOE at best. Getting a decent 4bbl manifold can be expensive, but not as much as your crossover + webers. idea. Check out Richardson Engineering, UK. for 215 stuff. Were the Traco intakes steel fabricated or cast?
 
Mike
Its not too hard to fabricate from steel, inlet manifolds to suit the 4 carb set up, I have made two sets now running 40mm Del Orto carbs on the two Rover /Buick motor builds.
It takes approx 20 hours to fettle up a pair.
I would be happy to explain more if you wanted to proceed.
Regards
Russell
 
I already have a nice Ofenhauser 4bbl manifold & valve covers. But this car's going to be a road & show car. I've always lusted over the looks of a 4 carb set up. Whether cross over or down draft. I have 3 Webers (40 DCOE) & 4 solex side drafts. I'm not really sure about the original manifolds. The ones I've seen clear enough engine picture. At least the down drafts look to be cast. I'm one that likes to be sure things look right as well as working right. Very visually oriented I guess.
 
WOW Thanks Ian those are what I really wanted. I particularly like the down draft look. Of course that means I'd have to but 4 carbs too LOL Now I'll have to make up my mind which I want. Their prices are about 1/2 of what I was looking at.

Russel I suppose yes they could be fabricated from steel or Aluminum. Did you do a down draft or cross over? Yes the Rover/Olds/Buicks are the same. Only real difference is in the heads. The Olds has one extra head bolt per cylinder. I suppose that's why they mostly used the Olds in racing?
 
Mike, the quad DCOE set up can be a really nice fueling system - both visually and functionally.

One thing to keep in mind: having four DCOE's is not sufficient in itself. For the thing to run properly, you need four DCOE's of the same configuration. In other words, you need to ensure the numbers that come after "DCOE" (such as "9" or "13" or "152") are all the same. This is because these numbers mean (among other things such as jetting) the size and relative position of the progression holes drilled in the side of the bore. The relative size and position of these progression holes is the primary way AFR is controlled between idle and WOT. The jetting also has an impact here of course, but the primary means AFR is controlled in part-throttle is by way of the size and position of the progression holes. Bigger holes, and more holes, placed in proximity to the closed butterfly means a much richer progression off idle than small, and fewer, holes....just for example. The number after "DCOE" correlates to the particular progression hole configuration.

With multiple weber configurations, half the problems people experience with tuning are related to not having matching series webers. The other half of problems relates to poor linkage (as JacMac pointed out). The black art of tuning webers really isn't that complicated once you have matching webers and good linkage.

If you're really interested in understanding how to work with multiple webers, best thing to do is read Pat Braden's book - "Weber Carburetors" (available on Amazon). Everything you need to know is in there.

Good luck!
 
Thanks Cliff I have a good friend who's been in the business of race cars for many years. He knows a lot about such things & is my go to guy for such set ups.

Ian thanks a lot I'll check out those leads. Over here in the States the Buick/Olds/Rover engine is much over looked. Every body wants a Chevy or Ford & not much else available as speed equipment.

This is what's so good about enthusiast forums. The sharing of information & suppliers around the world.
 
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