Grp a venturi? Its taking a step back in time with the knowledge of tuning the std carb on this site. Save your money
The bored out standard 25mm venturi loses the actual venturi effect and therefore the fuelling is difficult to get right. I'd have though that if these 26/27mm Group A ones are better shaped and retain the venturi effect, then the fuelling will be easier to get right and in theory should work a whole lot better than the old tuner jobbies.Someones going to have to try them!
There is a lot of scare mongering about Group A Carbs, but this is because of all the very bad tuner imitations. Guy's in France have been running these for some time and with some success in world of motorsport.
I think someone needs to get on the French forums and gain some real feedback as it appears everyone is shooting from the hip at the moment.
Last edited by Woznaldo; 11-12-2015 at 20:50.
can some give me the link to the page that sells these thanks
Can someone please send me a link to the supplier of these kits please
Send Woz a PM he might be able to help?
A word of caution. I bought the Grp A venturi and Doris never ran well with it in. Ian Nixon couldn't get her to run right kept spluttering when you tried to accelerate and over fuelled back fired into the carb the works.
However I will be watching to see if you guys can get one to run well.
i'm going to have a fettle of my carb as my last base had a knife edged spindle and throttle plate but couldn't get the screws out and the spindle bushes had worn when i tried to rebuild it.
So used another base i had and put new end seals in
The aux venturi interests me and wonder if just changing that would give any benefits
As the brass tube look a different length, I wonder if the changed the position of the narrow region the main venturi?
What boost were these intended to work at? Would there be an optimum flow rate and they're not so good each side?
The cup cars (track) were limited to 14PSI.
The question is, why weren't the company or its contact details ever posted on this thread?
Anyway, not that it is much use but I have managed to find the person who I 'think' Woz was in touch with back at the start of the thread. A guy called Mike-11turbo who is from Switzerland.
If you look at these pics from a thread on the http://www.gtturborhone-alpes.fr/ forum (which I had to become a member of to be able to read the thread), you can see it's almost certainly the same workbench:
These pics are from Feb 2013.
This is not much use though. I looked for some time yesterday for the company making the kits but couldn't find them.
It may be a good idea to get 1 set up and running use it as a comparison to our modified standard carbs, also sort any teething issues and to see the real difference.
By any means it's a fantastic find and great opportunity.
Here's a link to a place that sells them. Not the original place I found, but looks ok from the limited pictures?
http://jettautosport.e-monsite.com/b...r-gra-jas.html
Bang up Woz
Only 55 Euros + tax! Is this everything that's needed?!
Looks like there are options on the venturi diameter too.
Wow, thats a good price. I might try one, just coz. Virtually all of the old tuner 'GP A' carbs were just a large venturi. It's rare that you see them with the brass aux venturi.
Obviously, like the std Carb, the setup of these Gp.A Carbs is critical. Here's some setup info, that I think you get with these kits, but if not it's here.
As you can see, it does need some translation, but I'm sure some of our French brothers will step in?