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Posted by: djfamousa May 30 2007, 07:17 PM

After many shenanigans with trying to get the FI board refurbished, I have decided to give up my quest and go dual carbs. I know, I know, It was not an easy desicion for me to make and I have waited a whole year almost and still don't have my car (1974 1.8).

Ok, now to my questions... What is the best performing dual carb setup for a stock 1.8 motor? (i am looking for a dual carb setup that I can put on the car and will work w/ the stock engine). I'm trying to avoid changing out the cam for now.

In the future I would like to change the cam but can i simply rejet a dual carb setup to work with a new cam?

All help is appreciated greatly! Thanks!

Posted by: Joe Ricard May 30 2007, 07:25 PM

Dual 40 IDF's with 28mm Vents.
Jetting is tough to nail down not knowing exhaust, ignition and climate you run.

50 Idle jets, 125 Main 180 air is a complete stab in the dark

Posted by: SirAndy May 30 2007, 07:26 PM

40 IDF webers with tall intake manifolds and a good linkage (like the CB performance linkage).
use the thick FI gaskets to mate the intakes to the heads.
also, get a rotary fuelpump (again, from CB) and read the article below on how to hook it up ...

http://www.914world.com/specs/SirAndyCarbFuelPumpRelay.php

Andy

Posted by: djfamousa May 30 2007, 07:39 PM

I live in Los Angeles California, engine and exhaust is completely stock but the engine was rebuilt to stock specs at some point. I also have a crane optical ignition fireball 700 or somthing like that.

Will the suggested setup, "50 Idle jets, 125 Main 180 air is a complete stab in the dark" work for me here in Cali?

Posted by: SirAndy May 30 2007, 07:50 PM

jetting is a artform all by itself. i'm afraid you'll have to tinker with it, one way or the other.

the suggested jetting above should at least get her running ... then you go from there ...
Andy

Posted by: Joe Ricard May 31 2007, 06:07 AM

Agreed I have a huge assortment of jets. and reamers. I usually go to a whole different set up during the hot humid summer. 95 degrees 100% humidity. vs. 40 degrees and 30% humidity. that's like one whole jet size.

Posted by: SGB May 31 2007, 09:07 AM

Joe-
I am curious what other jets you run and when. I have recently gone through a long trial and error procees with my 40IDF webers (with 28mm venturis) on my web-cammed 2 liter. I finally settled on 50 idles, 120 mains, and 180 air jets. I had 55 idles and 125 mains and it fouled plugs regularly. I also had 200 air jets and it ran hot at high revs. With 45 idles it runs hot at all revs.
So I think the 50, 125 and 180 is probably gonna be good. Maybe 120 main jets and 190 air jets for a 1.8 to lean it out at speed...

Posted by: Joe Ricard May 31 2007, 09:20 AM

1st of all YOUR MILAGE WILL VARY

Everyone should know what I was runnig in the Red Neck Racer by now.
7.6:1 compression 2.0L ported heads Tangerine EVO complete Mallory ignition. 86b cam. 40 IDF with 32mm vents.

sea level winter time: 140 mains with 250 air f11 tubes 55 idles
Sea level summer: Currently 135 mains 250 air f11 tubes 52 idles

I have a wide band AF meter. and full power WOT somewhere around 13:1 air fuel. this varies ALLOT with atmposphere. and maybe even gas brands. I ran 87 octane with allot more power than 89 and 91 just sucked.