C20XE Carbs

[mint nova]

Hi. I was wanting to run twin 45s on my XE but i have been offered a set of twin 40s. I was wondering if there would be alot of difference in power and performance between the them before i buy them. Any advice appreciated.

[adam c]

I think there was a thread about this the other week and the general concensus was that they would give better low down grunt but stuggle top end(have a search for it as my memory isnt the best!lol)

[Angus Closier]

They could work with big jets in them but would lack the correct air flow at top end. Id just go for a set of 45s but make sure they are the correct 45s and not just random. Make sure they have the correct number of progression wholes and have the right jets etc...

[bmw156]

i always understand it, as 40's would be stretched for an XE, but 45's would suit it naturally.

[C612DNM]

40's will work quite happily if jetted accordingly with up to a 32mm choke. You will see a power increase over the injection, and that lovely webster roar!

Go over 34mm on the chokes and performance will fall off.

45's with 36mm chokes and jetted correctly with provide good torque and more power than the 40's.

You could, however, use a 1/4" SU with a No.9 knitting needle. It'd still work, but be a little restrictive.

[Stuart]

a 1.6 on 34mm chokes works fine ;)

for the faff vs gain from 40'ing a 2.0 engine I'd just not bother (with a decent airboxed intake system you can get a great noise anyway)

45's/48's on the other hand... oh yes (but TB's would be my preferred weapon of choice in that instance)