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Twin 40 Dellorto's, Help With Experience/tuning/selection

Featured Replies

Hi all,

I'm going to rebuild a set of 40mm Dellorto's for the 5k, question is which type to use. A guy I have been speaking with is saying don't bother with the DHLA f,g or h as they are no good during the progression stage, and suggested hunting for a set of DHLA pre pollution type.

 

My question is, is anyone using the DHLA f,g,h models and are they OK? Does anyone have any experience going down this road with these carb types? I have four pairs in the garage, 2xf, 1xg, 1xh what should I use?

Your friend is right ,according to books i have the DHLA 40F,G,H,L AND N. are emissions carbs hard to get the progression phase right.

 

The ones you want are DHLA40 (no letters).

 

No i havent used them but they just as good as webers from all reports.

 

rob

From my research when I was looking into Dellorto's, people just don't understand how to jet the pollution carbs, it's different to the non pollution carbs, so people tend to give up. I've got a book about Weber and Dellorto tuning somewhere that does talk about the F and G carbs, PM me your email and I'll see if I can dig it up.

 

I'd probably use the carbs that are in the best condition as a base...

 

Some details here:

http://www.rsmotorsport.com.au/forums/viewtopic.php?t=2694&sid=e55b4c4ef1e0c12790914d42697e06b9

https://elthamracing.wordpress.com/2010/02/14/jetting/

 

I used to have a really good link on KP61.net that was K motor specific, but that site seems to have vanished.

 

The general gist seems to be, don't tune the idle circuit like a normal circuit.

  • Author

From my research when I was looking into Dellorto's, people just don't understand how to jet the pollution carbs, it's different to the non pollution carbs, so people tend to give up. I've got a book about Weber and Dellorto tuning somewhere that does talk about the F and G carbs, PM me your email and I'll see if I can dig it up.

 

I'd probably use the carbs that are in the best condition as a base...

 

Some details here:

http://www.rsmotorsp...0914d42697e06b9

https://elthamracing.../02/14/jetting/

 

I used to have a really good link on KP61.net that was K motor specific, but that site seems to have vanished.

 

The general gist seems to be, don't tune the idle circuit like a normal circuit.

 

PM sent

  • Author

Cheers guys,

I have now installed my reconditioned and recurved electronic dizzy, makes a big difference being able to run the correct advance. Very pleased with the results!

As for the carbs I think the best option is to rebuild the sets I have and sell three of them, install the remaining pair on my car and see how they go, if I'm not happy with the end result I can always hunt around for the pre pollution type later.

I am having some dyno runs done next week to get an idea of where I'm at (Allcraft Automotives), balance the Aisan's and get the idle mixture set properly.

I'm still playing with the twin Aisan's at the moment and they are going pretty good, new longer duration cam 240deg is on the way also up from 214deg

Edited by megamannz123

  • 2 months later...

I'm running a match pair of G's, I think you'll find the non-pollution ones are hard to find.

 

I got mine running ok at home, but there is very little adjustment (balancing etc) on them. In the end I lucked out, the Dyno tuner in the next suburb has an alfa nut and dellorto guru there. I daily drove the car for 3 years with no issue with the tune. Started first kick and ran like a dream.

 

68rwkw with a big cam and lots of comp.

  • Author

Cheers for the info!

Where did you have them tuned? In Melbourne? I have rebuilt two sets so far but not installed as yet.

I made 64kw @6000 with the Aisan carbs so might get a bit more once the delortos are fitted.

 

edit. I see your in Adelaide, couldn't see that on my phone.

Edited by megamannz123

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