gene cooley
Autocrosser
Carl, what size are your venturies in the 40s?My motor is stock with just a header/turbo muffler and dual 40 IDFs. The motor has razor sharp throttle response right off idle. My car is driven in a suburban environment where sitting at traffic lights for a few minutes is common. I do have my favorite sporting roads not far from the house. I agree with Mike, they stay in tune and if there is a glitch it is usually dirt in one of the jets. I will admit a single carb has a steadier idle but that's about it. I don't advocate carbs or even dual carbs to anyone. I like them and my Fiat is a toy and thus a recreational release for me...as opposed to my Miata which is just a nice little sporting convertible.
We had 36s in our 40 IDFs on the AM formula car (900#, 2200cc) and they worked ok there, but I don't think they would provide good throttle response on a 2000# 1500cc X with a big cam.
Just depends on how things are tuned.