1776 single port to dual port

[firerod]

I have a very low mile 1776sp with stock internals and stock single carburetor. If I changed this over to a dual port with dual Kads would there be a noticeable power increase to make it worthwhile?

[b-man]

Night and day difference.
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1956 Dove Blue Panel
1966 Velvet Green Single Cab
1957 L41 Black Oval Window Beetle

[oprn]

Unless you already have the Kadrons, Webers are about the same money these days and are head and shoulders better. I would never go back.
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Our cars get old, we get old but driving an old VW never gets old!

[jsturtlebuggy]

Yes you feel a difference in performance from what you have.
Kadrons work well for your size engine.
A set of 40IDF dual throat carbs would work too and usually run smoother then then the Kadrons and have more power.
Depending what vehicle you have getting to spark plugs can be more difficult to with the 40IDF size carbs
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Joseph
Fair Oaks/Orangevale, CA
Elrod Motorsports
Motion Tire Motorsports
Having fun with Dune Buggies since 1970
Into Volkswagens since 1960

[Rome]

[DerrickfromNC1]

[firerod]

Thank you all for your replies. I already converted to a doghouse cooler when I had the engine built. I also already have the dual Kads. The reason we went with a single port is the worry of overheating the heads and cracking them in a convertible, top down in the summer. Now I am just thinking of more power.

[Dusty1]

[oprn]

[oprn]

[jsturtlebuggy]

At one time there were single port manifolds made for the Kadrons.
Kaddie Shack shows all the ones they had are sold out.
Contact them and look in swap meets you might find a set.
If you stayed with single port heads and used the Kadrons you still notice a performance increase.
Last single port set I was involved with was in the 1970s and they were the steel ones.
_________________
Joseph
Fair Oaks/Orangevale, CA
Elrod Motorsports
Motion Tire Motorsports
Having fun with Dune Buggies since 1970
Into Volkswagens since 1960

[firerod]

That is a thought, dual Kads on my single port.

[oprn]

There is something inexpensive enough to be worth a try. Find an old single port manifold, cut off the lower bits, cut and roll the next up elbows upright, make some carb bases from flat plate and weld it all together.
_________________
Our cars get old, we get old but driving an old VW never gets old!

[Rome]

^SP Kadron manifolds have become hard to find; none are made new AFAIK (edit- see my next post). Used ones come up occasionally... oprn's idea of making a set is viable considering the "rarity". Instead of trying to straighten the strong bend of a segment from a stock SP intake manifold as the mostly straight piece going between the head base flange mount and the carb base, you can use the straight (horizontal) section of the stock manifold pipe starting from the left side of the carb downpipe. You thereby need 2 manifolds, but those should be cheap at swap meets especially if the preheat pipes are tested to be clogged (blow into either end). You're cutting the two end flanges off anyway as the bases for the Kad manifolds, so the rest of the factory manifold is "available" anyway.

Another choice for making the long manifold pipe section would be a pair of dual-port factory manifolds. The curved down-pipe from the carb flange should have a larger OD than the straight/level pipe from the SP manifold. And stock DP manifolds are also very cheap at swap meets.

The Kad SP manifold pipe widens as it goes up towards the carb attachment flange, to make room for the carb's 40 mm throttle plate to swing downwards at full throttle. You'd need to force the stock factory manifold section apart to a wider diameter using a cone-shaped "muffler reshaping tool" while the pipe is heated red-hot... And I don't know if the metai has enough "stretch" for this reshaping.

Instead of sectioning the manifold for the straight section, I've often thought about using a section of exhaust connecting adapter pipe from a FLAPS. You'd need a piece with an OD of 1.2" to fit the stock manifold pipe's bottom flange, then tapers out bigger for the Kad's carb larger bottom flange. IIRC the smallest adapter pipe I've seen at FLAPS are 1.5" OD on the small end... If you can find one with an OD of 1 1/4" at one end and going up to 1.5" at the other end, that would be nearly ideal for the project.

I have a steel SP Kad manifold in the basement which is for an upcoming engine. I just measured it:
-The pipe's OD at the bottom flange (at the head) is 1.25". The straight pipe comes up out of the flange straight out/perpendicular from the flange; it does not lean outward or tilt forwards. The longest dimension of the straight pipe to the underside of the carb flange is 5 3/4".
-The OD of the pipe just under the carb flange is 1.6".
-The carb flange is tilted approx. 17 degrees, which should be the same (but tilted the other way) as the outward tilt angle of the SP head's manifold flange. This angle would bring the carb flange to a horizontal/level angle for the carb.

For the Kad carb's attachment flange, a piece of steel of appox. 1/8" should be sufficient- such as traced out from a stock oil pump cover. Use a hole saw to cut the center large hole for the throttle valve. It would need to have an OD which is slightly smaller than the OD of the pipe (just under 1.6") but at least as large as the 40 mm throttle diameter. A 1.5" hole saw would work, then you'd need to slightly enlarge it using a curved metal file. AFTER you weld it to the pipe.

[Rome]

Aha- here's a new set of SP Kad manifolds! But "sold out".
https://aapistons.com/products/sp-kadron-aluminium-manifolds-compatible-with-solex-h40-44-eis

[Dusty1]

[oprn]

!0,000 old fat guys in speedos and big ladies in bikinis might think they look hot too but that isn't necessarily the opinion of the general viewers...

Yes we have been conditioned to accept open engines on Bajas and Buggies but engines in and of themselves are not exactly beauty queens. We dress them up with expensive shinny bits to help make them presentable much like today's trend to cover fat rolling bellies and bulging pendulous bosoms with tattoos to deflect the attention... but deep down engines are still just ugly bits of functional metal all stuck together without form or flow. Not much artistic merit there.

Each to their own...
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Our cars get old, we get old but driving an old VW never gets old!

[Dusty1]

[oprn]

I will pass on that one thank you very much!


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Our cars get old, we get old but driving an old VW never gets old!

[BFB]