Need Weber tuner in metro-Detroit

[Mawgui]

My Caterham arrived Monday in Detroit from Albuquerque by way of BaT. Car gets loads of thumbs up. Webers clearly need to be retuned for lower altitude. The owner-installed choke makes starting easier. But the car pops intermittently and needs a proper adjustment of the Webers. My first stop was the gentleman who works on my TVR but he says he hasn't the jet kit necessary to tune DCOE Webers.

I'm hoping someone on this forum can make a recommendation on who can tune my carbs?

Thanks!

[NSXguy]

It’s a dying art with fewer proficient practitioners. Might check with vintage race shops or older Porsche shops. 
 

if inclined to tune in your own, you can start by sharing your current baseline jet settings. From there you can likely start by a 1/4 turn out on the mixture screws (may have to go up in idle jet is it doesn’t cure) and then proceed to optimize the main circuit based on driving feedback. 

Edited Thursday at 10:34 PM by NSXguy

[Origin7]

I just went through a similar situation. Even a shop with a reputable pedigree couldn't tune it well, so I did it myself. Hope this thread helps: 

 

 

Message me with any questions. 

 

 

[IamScotticus]

Popping can be an exhaust leak.  seal all the pipes with high temp silicone.  and, you could bolt the manifold directly to the head face.  Lots of xflow 7ers do this.

 

Another issue with DCOEs is ensure there is ample tension keeping the starting "choke" circuits closed when not being used.  And locking them closed wirh zip-ties when road tuning so they aren't fooling anyone by dumping gas while driving.   I have  read about the choke circuit springs replaced with stiffer, and start circuit delete kits are available to solve these problems. 

I say all this to point that there are a few problem areas around the carb to be checked before tuning can commence. 

And you might find the source of your problem not being the carb at all.

 

Edited yesterday at 04:00 AM by IamScotticus

[toldfield]

Look at Sidedraft Central and see if Keith has a starting point for you.  He was a huge help to me and knows more about Webers than the Weber.

 

Tom

 

sidedraft@vintagetechnologygarage.groups.io

 

 

[Croc]

18 hours ago, Mawgui said:

My Caterham arrived Monday in Detroit from Albuquerque by way of BaT. Car gets loads of thumbs up. Webers clearly need to be retuned for lower altitude. The owner-installed choke makes starting easier. But the car pops intermittently and needs a proper adjustment of the Webers. My first stop was the gentleman who works on my TVR but he says he hasn't the jet kit necessary to tune DCOE Webers.

I'm hoping someone on this forum can make a recommendation on who can tune my carbs?

Thanks!

 

 

 

 

In case you have not found it, then the library has reference material on Webers:

 

 

and here

 

 

 

I have 9 of the little devils installed on cars.  Most of their problems come from modern fuels drying in the carbs and leaving residue.  To stop that you want to install a fuel shut off valve so you always run the carb dry instead of using key to turn off ignition.  Then the tune you set will be preserved long term.

 

However, that does not help you now since you need to get to a good tune as a base foundation.  Lots of old Formula Fords and other types of race cars use Webers - find a race mechanic specializing in old equipment like that.  I bet there is one locally to you in Michigan if you ask in a race forum for those SCCA or NASA classes.

 

The pops on liftoff are more likely air leaks in the exhaust manifold as Scotticus notes.

 

@SK400 Do you know a good race shop near you that does older open wheeler stuff please?