Looking at slide throttle
07-23-2008, 03:30 PM
#2
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Join Date: Sep 2002
Location: Savannah, Ga
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Im not specifically familiar with slide throttles on a car, most of what I know is bike related. But I do know this. Running slide throttles on a bike without a throttle return cable(that forces the plates closed when you twist the throttle closed) is generally a really bad idea. The vacuum from the engine can put such a load on the plates that they cant close fully. Some motorcycle slide throttles use a vacuum breaker, but I havent seen exactly how they are designed.
I have thought about it and thought about it, and I still think slide throttles only have a place on pure race engines, and not even all of them. With a little massaging, you can get nearly the same flow from regular throttle plates, and without the associated risks of slide throttles.
I have thought about it and thought about it, and I still think slide throttles only have a place on pure race engines, and not even all of them. With a little massaging, you can get nearly the same flow from regular throttle plates, and without the associated risks of slide throttles.
07-24-2008, 04:59 PM
#3
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Location: Central Ohio (Hebron) Zephyrhills Fla.
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Originally Posted by Jeff20B' post='905263' date='Jul 23 2008, 11:45 AM
Who makes the best? What have you guys used? How thick is the internal plate and should it have a straight edge or some form of a rounded shape?
Lucas made some great slide throttles. I had one off of a Hart Ford engine. Sold it for a song. Wish I had it back now. It needs to have a hardened plate with square edged holes. It only flows well when wide open. Fuel injection is above the plate, so it must operate well in a fuel spray.
The Lucas slide has dozens of rollers to support the slide and provide effortless movement. Always run two return springs.
Good for 3-4% over a carb. Allows for straight runners on a in-line engine. Good spacing for a rotary, when cut in half.
Very light compared to two carbs. Very expensive now, probably not manufactured in 20 years with Throttle Bodies being lighter and cheaper. Used with high pressure mechanical injection, (Lucas). Can be seen at Vintage races.
I still have some air horns for one around here somewhere. Increasing the TB size on individule runners, just a bit would match the power and be way cheaper.
Lynn E. Hanover
http://www.lucasinjection.com/index.html
07-30-2008, 06:42 AM
#8
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Location: Central Ohio (Hebron) Zephyrhills Fla.
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Originally Posted by R.P.M.' post='905551' date='Jul 29 2008, 05:47 PM
This setup also made 40hp more than a properly jetted Webber carb on the same engine.
This whole setup was in this little gem
This whole setup was in this little gem
Pumps appear to be Lucas. Power increase would have to be from an increase in choke size.
Nice settup.
Lynn E. Hanover
08-01-2008, 08:29 PM
#10
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Originally Posted by mazdaspeed7' post='905423' date='Jul 26 2008, 11:03 PM
least helpful post EVER...
cant you at least post some pics and details?
cant you at least post some pics and details?
IF you would have spent your time here in the past, instead of on EVIL and the kiddie forums, I have posted plenty of pics/details of my mazda slide throttle. Back to your swamp, coast dweller