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Sun Apr 22, 2012 10:22 am

Have a question about possible carb upgrade. Here's what I have.

Fresh rebuilt 1600
New 85.5 p/c
8.2 : 1 compression ratio
stock crank and rods.
Engle W100 cam and lifters.
ac.net L3 heads.
solid rocker shafts,Porsche 911 adjusters
Bosch 019 distributor
1 1/2 inch Tri-Mil header
dual Weber 34 ict carbs with short manifolds.

Engine seems to run well only 200 miles since rebuild

My question is would a carb upgrade to dual 40 idf or dellorto 36 drla be a worth while upgade for my engine combo.
I am looking for a more carb tuneability,idle quality and extra performance wouldn't hurt either.

Thanks any info appreciated.

Sun Apr 22, 2012 10:30 am

I think so. The idle and low end are so much better with dual 2bbls, the firing order causes uneven running with dual 1bbls.

I've also never seen anyone that had dual 1bbls regret the change to dual 2bbls. But a lot of guys with dual 1bbls regret not having the dual 2bbls

Thu Apr 26, 2012 12:05 pm

hi all i am trying to synch my dells 40 drla and am having trouble i have dual carbs in my 1970 vw squareback i cant afford the dell tech manuel right now because i spent all my extra cash just to get my car running after sitting for 6 years :( but i finally got it going my only problem are these dang carbs :twisted: I hope someone can help me out so that my 6 year old daughter wont be afraid to drive in the car with me she thinks its going to blow up :oops:

Thu Apr 26, 2012 12:30 pm

You should make your own topic to not hijack the OPs post.

Remove linkage arms to carbs on both sides. Set both idle-speed screws from just touching the throttle plate arm plate to 1.5 turn out on both carbs. Connect linkage arms to plates. Using your peripherial vision, ensure both linkage ( after tightened up) open and fully close both carb plates evenly. Set each AF mixture screw from fully closed to 4 full turns out. Start car and allow to warm up a little. Idle speed may be a little high. You can bring it down a little to about 1000 rpms. Fully close each mixture screw individually till the engine rpm goes down and engine starts to cut out. Very slowly open one by one on the screws till engine speed is constant and even. Readjust idle speed down as necessary This is how I do it. After practice you can do your valve adj, timing and carb adjust in 15-20 min total.

Baseline jetting: 1.5x intake valve size = idle jet
Venturi x 4/4.1/4.2 -stock/mild/performance= Main jet
Id stick with a 200 air for yours but the 40 dells usually come with 180 air. You will need to use one step down on the mains or drive and test.

This is just a basic formula used. You will need to drive the car, note holes, lack of performance, rich conditions, and read plugs to adjust up or down on your jetting.
Good luck.