installed the update kit (and the jet doctors). after a little test and tuning i gotta agree with dmarks (in a previous post)this is well worth the 135.00
i really was suprised at the overall increase in power. i would recomend it highly to anyone running webbers.............my 2 cents

(Upgrade Kit)

What is involved in installing those? Just pulling the stock stuff out and slipping in the new fuel sprayers? I was thinking about kits for my carbs.

Roy

actually its a very simple upgrade. it can be done with the carbs installed. just gotta remove the top half of the carb and replace the venturi's and change the main jets. took about an hour

So is that all it is? A different set of jets and vents? Or are they made differently, not just a different size?

Thanks, Larry

There is more to the upgrade than that. They use a spray tree for better atomization of the fuel that allows a much finer mix with the air and less fuel condensing on the carb barrels.
Heres the link: http://cbperformance.com/catalog.asp?ProductID=508

I put the update kits in my 45 dells and lost low end power, the kit replaces your vent. with a slip in aluminum vent. that is the size of you barrell,there is no size to choose from for fine tuning,it will be like putting a huge vent. in your carb. youll have great top end but I believe it will hurt your low end for hill climbing.I put just the jet doctors in my webers and that will help keep your idle jets clean,just my experience with update kits

When I put them in my 44's I didn't lose any bottom end. I did have to go to a smaller idle jet because I was fouling plugs while trail riding. MSD should take care of that.

i had to go from 60 idles to 65's. the power increase is noticeable across the board.(from the update) dont know if msd ign. and a 2165 stroker moter have anything to do with it. according to c.b.performance the dell update didnt work well in the webber carbs. the webber update was shelved then revised apparently they got it to work.