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slide throttle carburetor
silver - December 11th, 2012 at 11:31 AM

Has anyone used or considered using this type of carb in street cars either for performance or daily use
they look interesting. I cant see why not

http://revmasterautomotive.com/revmasteraviation/?p=206 


Grey 57 - December 11th, 2012 at 11:57 AM

Porsche used sliding throttles in racing cars in the 70's


Birdman - December 11th, 2012 at 08:49 PM

Slide throttles are not used in street cars because of their tendancy to jam.


Gracey - December 11th, 2012 at 10:00 PM

Flat slide carbies have been used on motorbikes for years, I've owned a few and they've never jammed on me.

I'm not sure why they're not as common on cars, maybe price.


silver - December 12th, 2012 at 03:42 PM

Quote:
Originally posted by Birdman
Slide throttles are not used in street cars because of their tendancy to jam.


but these are from an aircraft application their reliability would be paramount


Birdman - December 12th, 2012 at 08:56 PM

not much dust and gravel in the sky :lol::lol::lol:


vlad01 - December 13th, 2012 at 02:21 PM

why stray from traditional butterfly when its a simple fail proof design?

I see no advantages of using other designs over the butterfly.


what next? iris throttle? :lol:


68AutoBug - December 13th, 2012 at 07:15 PM

Many of the carbies I've seen on Motor bikes have had slides

as did the old VICTA Mower... lol

they must be simpler with less moving parts...

I agree Vlad that once a carby like the Solex PICT series was made and worked well, and then they just made them better
with improvements...

but up in the air.... lol

a slide type of carby is going to give less trouble than one with butterflies... I would guess... lol

LEE


vlad01 - December 13th, 2012 at 09:08 PM

how do you get more trouble from butterfly?

more/less moving parts? they are the same. only 1 part moves !


silver - December 13th, 2012 at 09:13 PM

When the slide is in wide-open position, there are no other obstructions in the way of the air flow except for the needle, thus allowing for much greater air flow than with throttle bodies which have typical butterfly valves. The flat side of the needle is oriented towards the engine and produces a low-pressure on the back side which in turn causes fuel to flow in relation to the air flow.
Under certain moist atmospheric conditions with air temps ranging anywhere from 20 to 90 degrees F it is possible for ice to form in the induction system. The rapid cooling in an induction system using a float type carburetor is caused by the absorption of heat from the air during vaporization of fuel and, also due in part to the high air velocity, causing a low pressure area through the carburetor venturi. As a result of the latter two influences, the temperature in the mixing chamber may drop as much as 79 degrees F below the temp of incoming air. If this air contains a large amount of moisture, the cooling process can cause precipitation in the form of ice, generally in the vicinity of the butterfly which may build up to such an extent as to cause engine stoppage. In a float type carb, the fuel jet is ahead of, or just below, the venturi and throttle butterfly which means that the fuel is being impinged directly in the worst possible place for icing…the carb venturi. Since the RevFlow injector carburetor does not contain a venturi, nor a butterfly valve, the fuel and air is mixed further downstream, beyond the float type venturi refrigeration chamber. The absence of these parts accounts for the decreased likelihood for ice in this type of system.


matberry - December 13th, 2012 at 09:28 PM

Quote:
Originally posted by silver

but these are from an aircraft application their reliability would be paramount
I agree but think of the difference in number of operations per hour. A car would have millions more operations of the throttle than an aircraft.


vlad01 - December 13th, 2012 at 10:23 PM

yes and modern butterfly TB in a EFI car have sealed needle roller bearings on the shaft and could easily outlast 5 engines and beyond from what i gather, having machined and made my own big boreTBs before.