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Twin Carb Manifold Identification

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Hi chaps,

 

Picked this twin carb manifold up at a swap meet today - couldn't believe my eyes when I saw it!

 

Question is, how do I identify if it's 3K-B or K-B?

 

Also, am I right in assuming this can be used efficiently with any matching pair of pre-emissions K or 3K carbs, presuming they are jetted accordingly for the engine (I understand the #K-B carbs had smaller jets than a standard 3K carb, and the K-B jets, whilst slightly bigger, were also smaller than single carb versions)?

 

I am aware it can be used with webers and adaptor plates, but I'll be looking for a milder setup and I can't see the point in spending more money on two 28/32 or 32/36 webers as I think it will be overkill for what I want.

 

Would I also be correct in assuming that the most difficult thing with this conversion (apart from finding a couple carbs) would be linkages? Is there a kit / setup available which can be used or adapted to make the job easier?

 

Any other issues I am likely to run into with this conversion?

 

My intention would be to put them straight on my stock 4K, and eventually work the motor and re-jet to suit.

 

Thanks guys in advance for any advice you might have.

 

post-1424-0-37066800-1318748829_thumb.jpg

 

post-1424-0-61003500-1318748844_thumb.jpg

 

post-1424-0-78655500-1318748861_thumb.jpg

Edited by TOM

I'm probably very wrong... But i thought the only k series engine to come out with twin carbs was the 3k-b?

Nice find.

 

On a 5k, I just used a couple of "single" carbies bolted onto the manifold. This worked fine.

 

The second set started off exactly like yours, a bare manifold. Added a couple of carbies which was easy, but the linkages took a bit of fiddling and the airclearners took a lot of thought. For the linkages, I dug up a throttle cable bracket that bolted to the base of the carbie instead of the rocker cover. This allowed the cable to operate the rear carbie like normal. The issue was running the front carbie. Tried making up a metal bracket thingy to link the throttle shafts together but any misalignment caused the carbies to jam open. Not fun :blinks: Ended up using a piece of rubber hose (either old fuel hose of steam hose can't remember) pushed over the ends of the throttle shafts and hose clamped in place. This resisted twisting enught so they carbies worked in unision, but was flexible enough to allow for any misalignment. Definitley run return springs for both carbies!!!!!!!!

 

For the aircleaners, my uncles had some chrome aircleaners to suit old holden carbies. Unfortunately they didnt fit the Toyota carbies :( Grabbed a couple of old Corolla aircleaner housings and welded part of the base of these into the chrome housings so they would mount to the Corolla carbies.

 

There are some pics around on this site of what I did but I couldnt find them last night.

This link shows some of what I did but not in much detail. Think the photos I was looking for were in one of Camerondownunders posts

  • Author

Thanks guys for the answers and advice.

 

The linkages sound a bit scary, but I reckon it's worth a go. I've found an air cleaner froma twin carb Triumph which I think I can adapt/modify to fit, so reckon I'll give this a go!

 

What are people's opinions on the potential of this setup as opposed to a single 32/36 on an adaptor plate or even a single 40mm side draught?

 

Cheers,

Tom

I have actully just bought a 40 dcom and thinking about selling the twins but got abit trigger happy and hooked it up without rejetting the weber and it was a very unhappy and spat a big dirty flame at me lol

Edited by ohwhatafeelinke30

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