4k Twin Carbs

[philthy30]

hey

just been helpin a mate build up a 4k for his ke20 got it all running but its got factory twin carbs on it and wont idle. it runs sweet above idle but no matter what we do we can't get it to idle by itself. i checked fuel pressure it was at about 3 psi is this enough for the factory twin carbs or do they have more ?

Any help would be greatly appreciated

 

cheers

Phil

[towe001]

Have you checked the timing ?

The idle jets could be crapped up.

Not enough vacuum. Twin carbs need a higher vacuum then what a single does.

 

It also comes down to whats been done to the motor as well - the idle jets just may not be pumping enough fuel to keep the motor alive so to say

[Redwarf]

Check for an air leak between the head and manifold.

[silverra23]

most old school carby's only require 3-4 psi. any more and they flood and don't idle either

[altezzaclub]

The engine won't use any more fuel at idle than a single carb, so fuel pressure is fine.

 

Has to be blocked jets or air leak...

[Taz_Rx]

Does it have a cam in it?

 

Don't expect it to idle at 500rpm like a stock motor if so.

[philthy30]

yea its had all the usual stuff done to motor got a fairly big cam. no air leaks and definately not leaking at the manifold might have a look at the vaccum side of things cheers for the info guys

might just put my single carb onto it, atleast i no that runs and get it running good first.

[nhillau]

hey,

do you have the fuel cut off solenoids plugged in? i had that trouble on my 30