Single Dellorto Dhla 40 Settings

[billkara86]

Hi all.

 

Ive aqcuired a Dellorto DHLA 40 and am thinking of sticking it on my corolla. At the moment it is a 3K, with extractors, exhuast, and maybe a mild cam (not sure). May put a 4k in it in a couple years, but the 3k is staying for now.

 

My question is, what settings (chokes, jets, emulsion tubes etc) are people running on single dellortos? I can only find info on twin setups.

Or if someone can point me in the right direction in which settings to start off at?

 

Thanks!

 

Bill

[GJM85]

Your setting will be small... Real small.

[philbey]

there are a couple of sites that explain jet and emulsion tube sizing on the net, I can't recall their address right now. It's a fairly straightforward calculation.

 

BUT If you really want results, just find a good dyno tuner with a stash of jets and let them sort it all out. Best 300 bucks you'll ever spend.

[billkara86]

the only sites ive seen that explain this are for twin dellortos. am looking for single setups.

 

if an engine running twin 40s requires:

34mm Chokes

140 main jets

7772.10 emulsions

180 air correctors

40 pump jets

40/7850.1 idle jets

 

what would be the equivalent for the same engine to run a single 40?

 

i would like to give it a go myself before i take it for a dyno tune.

[snot35]

Well you're probably running out of choke size. Generally 34mm is the largest that should go into a 40. If that's what you need for your tune with a single then it's going to be too small.

 

According to my Weber Dellorto book they suggest for minis (1275, probably a reasonable starting point), 45mm carb with 36mm. From there it suggests 160 mains, 7772.6 emulsion tubes and 180 airs to begin with. 45/7850.1 or .2 for idles.

 

Of course, all this goes out the window if you have emissions DHLA's which are identified by the complete number on the carb, you'll find this stamped on top of one of the throttle bores and it will be something like DHLA40G etc.

 

If you have a DHLA40F,G,H,L or N then it's an emissions carb and you're probably better off finding a tuner who doesn't sound confused when you tell them what you have and taking it there. Many of them come off of Alfa's, so it might be work contacting an Alfa club and seeing where they get all their tuning done.

 

Good luck!

Edited April 26, 2012 by snot35

[philbey]

I found with my DHLA G's there is a lot less functionality on them than other dellorto's. Early dell's you can actually balance each individual throat, but these ones have the ports blocked so they obviously managed this a different way.