There was a post about motorcycle itb's and the consensus was too big.
I've seen 1108 fire engines run well on twin 40dcnf carbs, although the choke size reduced the effective bore.
Injection systems tend to have better low end manners than carbs plus although the 600/1000cc etc bike engines developed peak power at very high rpm they still run well at low rpm and often have more power than my engine there too!
I saw a mini 1000 with a twin cam 8 valve head running 40mm itb's and it pulled hard from low down to 8000rpm no problems.
With injectors spraying into the inlet ports fuel stay atomized even when air speed slows down unlike having an oversized carb.
I think someone should definitely experiment with some bike itb's.
My first car was 1000cc and I had a 40dcoe, even on a standard engine it ran excellently..... Admittedly it was just 2 Venturis for 4 cylinders.
I also had a 2cv with a 40dcnf adapted to standard manifold with an awfully home made adapter with a steep angle!......no extra power.
Another example is the fiat 126 manifold for the single inlet port head for the 40dcoe!
Huge carb into a tiny hole!
I can't see how that will be of much benifit unless the area of the head port is similar to the cross sectional area of the carb Venturis?
What is the port diameter of the fire 1108 engine?
I'm sure there must be some itb's to suit?
36 to even 40mm.
Obviously you won't make use of the itb's max potential but if set up right should run ok with a big gain in power.
In fact Newman cams suggest twin carbs or itb's and kenvey etc don't do smaller than 40mm....I think?
I saw some itb's go for £50.... with injectors.....!
Or alternatively make a manifold using 2 itb's?
I've seen 1108 fire engines run well on twin 40dcnf carbs, although the choke size reduced the effective bore.
Injection systems tend to have better low end manners than carbs plus although the 600/1000cc etc bike engines developed peak power at very high rpm they still run well at low rpm and often have more power than my engine there too!
I saw a mini 1000 with a twin cam 8 valve head running 40mm itb's and it pulled hard from low down to 8000rpm no problems.
With injectors spraying into the inlet ports fuel stay atomized even when air speed slows down unlike having an oversized carb.
I think someone should definitely experiment with some bike itb's.
My first car was 1000cc and I had a 40dcoe, even on a standard engine it ran excellently..... Admittedly it was just 2 Venturis for 4 cylinders.
I also had a 2cv with a 40dcnf adapted to standard manifold with an awfully home made adapter with a steep angle!......no extra power.
Another example is the fiat 126 manifold for the single inlet port head for the 40dcoe!
Huge carb into a tiny hole!
I can't see how that will be of much benifit unless the area of the head port is similar to the cross sectional area of the carb Venturis?
What is the port diameter of the fire 1108 engine?
I'm sure there must be some itb's to suit?
36 to even 40mm.
Obviously you won't make use of the itb's max potential but if set up right should run ok with a big gain in power.
In fact Newman cams suggest twin carbs or itb's and kenvey etc don't do smaller than 40mm....I think?
I saw some itb's go for £50.... with injectors.....!
Or alternatively make a manifold using 2 itb's?