Webers for a VS Speedster

I have a 2004 Vintage Speedster with a 1915 motor.
Has anybody put IDF 40 or 44 Webers on a VS 1915 Motor without changing the cam, heads, etc?
Is it feasible to bolt on the carbs and dial them in without other modifications(Heads, Cam, ignition)?
Is there a noticeable difference in power?

You can definitely do it like that if your venturis are smaller. I sort of did it in my 1915 but I swapped heads for ported units with larger valves; I also installed ratio rockers (You can go up to 1.4:1 using the stock cam without problems of any kind).

I got 40 idf on my 1915cc. My heads are 40x35 (no port work just polished),cam is Engle 110,and stock ignition. They work out fine!!!

Beck's "standard" 1915cc C.B. Perf. engine comes with 44 IDF's.

Venturi size, and jetting are not that difficult to choose, if you get Tomlinson's Weber Carb Manual. All the tricks are in there.

Good luck....

Leon C.

Hi Lester!
Please be advised that a CB Performance 1915 is quite a different animal than a VS 1915... IMHO, I think you would be way ahead to stick with the Solex carbs. Those Webers can cost BIG bucks and not give ya a lot of "bang" on the VS motor. See the specs on the CB 1915 below:
http://www.cbperformance.com/turnkeys.asp#1915
Good luck!

Properly tuning Weber can become a hobby in itself. THey take alot of patience (and box of jets/venturies) to get running correctly.

I would for sure go with the 40's. Even with stock heads and cam, ect... you should have a big increase in performance. Resist the urge to over-carb your motor, sometimes bigger is'nt better. A smaller carb will run better at low throttle positions, and have a much crisper responce to throttle. The only benifit to larger carbs would be WOT performance, where your car spends about 2% of it's life, the down side would be your car would run much worse at all other conditions. Not to say that you could dial in 44's wo work, but with a 1915cc the 40's would be more than enough carb for your engine.

what carbs do you currently have on the motor?

martin

I believe that the carbs are Kadron?

Dual throat Webers or Dellortos offer more tuneability and performance than Kadrons; I know because I had Kads and switched to Dellorto 40's. Make sure you also swap your distributor for an SVDA as offered by Aircooled.net; it'll forever do away with the flat spot when taking off.

Kadron kits use solex carbs.

if you allready have dual single kads, you won't notice a night/day difference, if i were you, i'd either stick with the kads, or go to some dellorto 36's DRLA, or webber 40idf's. Those carbs are good on any engine <2000cc's.

martin

I've seen 48s on a 1914. I'm guessing that 110 would carry it. This one has 120.

Sounds like the general opinion is that I should either stick with the Kadrons or go with IDF 40's.
Thanks for the input....

I forgot to say that along with the things I did to my engine I also swapped the Kadrons the car had with Dellorto 40's. Webers and Dellortos are very similar and are better than the Kadrons; get yourself the Weber or Dellorto books from CB Performance and you'll be set.