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Why use 'Split' webers?
Xtreme Kermit - 19/1/12 at 07:50 PM

So carrying on the weber based discussion from the other day, why do people use 'split' webers?

I mean using two dcoe webers with one choke blocked off in each?

britishtrident - 19/1/12 at 07:55 PM

Siamesed inlet ports on A series heads heads particularly in BMc Minis, because a single Weber Dcoe didn't line up with the ports the resultant S bend it badly affect the gas flow and the mixture distribution between the two cylinders sharing the port.

paul Irvine - 19/1/12 at 07:57 PM

The main reason to use split webers is on an "A" series engine, they only have two inlet ports, if you use one choke on each carb you end up with a straight inlet tract and better air flow.

Paul

Xtreme Kermit - 19/1/12 at 08:12 PM

Ah - I get it! It's the angle of the dangle that causes the requirement

contaminated - 19/1/12 at 08:58 PM

quote:
Originally posted by Xtreme Kermit
Ah - I get it! It's the angle of the dangle that causes the requirement


Yup

Read a bit of David Vizard. Split webbers give you a straight line in the inlet and it stops the outer cylinders running lean in comparison to the inner 2 on an A series.

dhutch - 20/1/12 at 11:44 AM

quote:
Originally posted by paul Irvine
The main reason to use split webers is on an "A" series engine, they only have two inlet ports, if you use one choke on each carb you end up with a straight inlet tract and better air flow.
Strange, but it appears, true!

http://books.google.co.uk/books?id=oqqhmgbXZkoC&pg=PA96&lpg=PA96&dq=split+webers&source=bl&ots=4GpabJNCe_&sig=mpQJGJyOlGVV1g1Z BHajDkAW0VU&hl=en&sa=X&ei=CVMZT52RC5DHswaK9thI&ved=0CFEQ6AEwBg#v=onepage&q=split%20webers&f=false

http://www.google.co.uk/search?hl=en&safe=active&q=split+webers&bav=on.2,or.r_gc.r_pw.,cf.osb&biw=1308&bih=486&wrapid=tlif1327 05973770610&um=1&ie=UTF-8&tbm=isch&source=og&sa=N&tab=wi&ei=CVMZT52RC5DHswaK9thI

I guess it was a case of using what was available.

Daniel

dhutch - 20/1/12 at 11:45 AM

Second link is to a page of images, copy and paste whole link to get it to work!

Xtreme Kermit - 20/1/12 at 01:11 PM

well there you go - who'd have thought.

Thanks all - the collective does it again

Marcus - 21/1/12 at 03:04 PM

The other use was road rallying where you were only allowed to run 2 chokes. Was popular on Pintos and crossflows back in the day.