I'm looking forward to installed dual web cams on my Pininfarina 1983, any suggestions?
Price used /new?
Where to get them?
Thank You,
Henry.
Double Weber carbs
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henry
- Posts: 157
- Joined: Tue Apr 07, 2009 1:06 pm
- Your car is a: Pininfarina 1983
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mdrburchette
- Posts: 5754
- Joined: Wed Jan 25, 2006 5:49 am
- Your car is a: 1972 Fiat 124 Sport
- Location: Winston-Salem, NC
Re: Double Weber carbs
You may want to write something up in the parts wanted section. Don't be surprised to pay $800+ for a good set, along with a manifold. I prefer the 13/15s, which are the ones specifically for our cars, but people have successfully modified the 70s to work.
1972 124 Spider (Don)
1971 124 Spider (Juan)
1986 Bertone X19 (Blue)
1978 124 Spider Lemons racer
1974 X19 SCCA racer (Paul)
2012 500 Prima Edizione #19 (Mini Rossa)
Ever changing count of parts cars....It's a disease!
1971 124 Spider (Juan)
1986 Bertone X19 (Blue)
1978 124 Spider Lemons racer
1974 X19 SCCA racer (Paul)
2012 500 Prima Edizione #19 (Mini Rossa)
Ever changing count of parts cars....It's a disease!
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So Cal Mark
Re: Double Weber carbs
the 70s don't need any mods to work if you use the correct intake manifold
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sptcoupe
- Posts: 987
- Joined: Tue Mar 17, 2009 9:25 pm
- Your car is a: 1972 124 Sport Coupe
Re: Double Weber carbs
And the 70's have some improvements.
The accel pump nozzle is down in the bore and not above it like the 13/15s, which gets the fuel stream out of some pretty rough air before it gets into the bore. Much more accurate and consistent delivery and better atomization of the fuel stream.
You can also adjust the accel pump velocity with the spring loaded rod just beneath the accel pump housing, which gives you three adjustments to that circuit, rather than just the accel pump nozzle size and the bleed back valve size. And since the accel pump circuit is the one that cleans up many of the tractability issues with dual carbs, I find this improvement is really important.
And the emulsion tubes are taller, providing a bit of a "velocity stack" effect when you are at WOT and just on the main jets and the air correctors. This also improves atomization and allows you to avoid having to reduce the air corrector jet size when it is just a bit lean on tip in, and goung from just a bit lean to too making it too rich with a smaller air corrector jet (the famous puff of black smoke on acceleration). These improvements, in a nut shell, give you more flexibility in really fine tuning the carbs to your motor's particular build specs. The motor doesn't know the difference between the carbs - all that matters is the that it has adequate fuel with a consistently delivered, correct AFR.
The only mod you have to do is get the right manifold (like Mark says) ands cut off the excess throttle plate shaft between the carbs. That takes 10 seconds/carb with a vice and a hacksaw.
The accel pump nozzle is down in the bore and not above it like the 13/15s, which gets the fuel stream out of some pretty rough air before it gets into the bore. Much more accurate and consistent delivery and better atomization of the fuel stream.
You can also adjust the accel pump velocity with the spring loaded rod just beneath the accel pump housing, which gives you three adjustments to that circuit, rather than just the accel pump nozzle size and the bleed back valve size. And since the accel pump circuit is the one that cleans up many of the tractability issues with dual carbs, I find this improvement is really important.
And the emulsion tubes are taller, providing a bit of a "velocity stack" effect when you are at WOT and just on the main jets and the air correctors. This also improves atomization and allows you to avoid having to reduce the air corrector jet size when it is just a bit lean on tip in, and goung from just a bit lean to too making it too rich with a smaller air corrector jet (the famous puff of black smoke on acceleration). These improvements, in a nut shell, give you more flexibility in really fine tuning the carbs to your motor's particular build specs. The motor doesn't know the difference between the carbs - all that matters is the that it has adequate fuel with a consistently delivered, correct AFR.
The only mod you have to do is get the right manifold (like Mark says) ands cut off the excess throttle plate shaft between the carbs. That takes 10 seconds/carb with a vice and a hacksaw.