[hardflex]

I've got a single DCOE 42 sidedraft , which is like a 40 DCOE except the venturi's are held in by spring clip instead of bolts. Mine has a 27mm venturis. I got it with an engine I bought and it was never really sorted out. It's mounted on my 1500 spitfire which is stock except for headers.

First Question, I just bought some different jets and it is running pretty good now, but I notice the main jet kicks in at very low rpm's, around 1600 or so. There's almost no time on the progression circuit before the mains kick in. I attribute this to the 27mm venturi. These are not readily available to purchase but I can drill mine out to the size i need. Should I do that or leave it alone cuz it's working. I'm thinking 33mm would get the mains out to 2500 or so

Secondly, one site (i think it was CB performance) says you should drill a 2mm hole in the throttle plate when using as a single carb. I presume this is for VW applications but what is the purpose of this and would that apply to my setup also?

Advice would be appreciated. Thanks