$100T2

iTrader: (1)

OK, so since I'm a ******* idiot when it comes to carbs, someone who has a clue fill me in.

What size carbs work with our engines? Maybe, just maybe, this could be the definitive list and get moved to the archives.

So, let's say we have the following engines for street use:

12A
12A w/ SP
13B
13B w/ SP

What aftermarket carbs are appropriate? Namely, Webers and Dellortos... Anyone?

BlastinSideways12A

12A: DCOE 45 with 36-38mm venturis
12A SP: above carb or DCOE 48 with 38-40mm venturis
13B 4 or 6 port: DCOE 45 or DCOE 48 with 37-39mm venturis
13B 4 port SP: DCOE 48 with 39-42mm venturis
13B 6 port SP: DCOE 48 with 38-41mm venturis

Keep in mind that this is an approximation and it all depends on how well you tune them, along with other mods.

Sidenote: considering the cost of a Megasquirt and EFI hardware its hard to justify spending all the money for a Weber these days, plus its a hell of alot easier to make changes to the tuning with an EFI setup and you can be much more precise.

EDIT: you can also substitute Mikuni or Dellorto in for Weber. I've never owned either of the two but I hear Mikuni 44 kicks *** when setup right. I have used a DCOE 48 with 40mm venturis on my stockport 12A and it was too much carb. Smaller venturis would have helped alot. Bought the car with the carb on it and it was jetted for 10:1 air fuel ratios AT CRUISE! At WOT, it would start at around 11.7 or so and drop to low 10s by 7000. Anyway, I did put in larger air bleeds which weren't nearly large enough but it helped a little. Sold the whole fuel system to a friend who got the jets that the carb needed and he really likes it.