I have a 1.8 with the dual EMPI EPC 34's on it, they work great. I'm about to do a top end rebuild on the 1.8 and have the option to bump it up to a 1911. These little carbs are rated up to the 1.8, I'm thinking if I go to the 1911 I will need a little more out of the carbs. Has anyone gone to bigger jets successfully on these carbs? If yes how much bigger would I need to go? They come standard with 1.75 needle and seat, 150 main jet, 55 Idle jet, 175 air jet and F-6 Emulsion tube.

Thanks,

Jsaum

I did some digging around on the web and I found this, so I guess the 34 epc will run the 1911 if I want it to run like a 1600 cc bug!

So, let's say that you have a 1915cc engine and you want to know VW used a 28mm venturie in a 34 pict (34mm throat) carb for a 1600 (1584cc) engine.
That means they accounted for the engine running fine with 56.57cc for every mm of venturie (1584 div by 28 = 56.57).
If that rule of thumb worked for many years for many cars, then the same rule of thumb COULD WORK for you.
what size throat carb you should use on it.
Here's the math for that situation: 1915 div by 56.57 = 33.85mm or a 34mm throat size carb.

For carbs I'd only use dual IDF's or dells.
I'd put together a Ljet system before using a 2x single barrel carbs or a progressive.

I have those same carbs on a 2.0 and I think it runs great. I did have to bump up the jets to get it run good but I can't remember what I changed and to what size but most likely the mains because it ran good on the low end and stumbled at higher rpm. Before those I had 40 Empis and it ran a little better but sucked the gas. I do have a Web 86 cam which helps it run much better with carbs over the FI cam. I even tried the hated progressive 32/36 Weber and had good luck with it. I really liked the electric choke for the cold high desert morning starts and never had the intake freeze up that everyone talks about even in 20 degree weather. Good luck with whatever you decide.

I have a set of 36 dells just need to go through them. I also have an L jet in the works too. As a short term stop gap measure I might try going up one size on the main jets on the 34s. I’m trying to stop myself from having a half dozen projects going at once.