throttle travel

[Allen Lofland]

I am not getting full throttle on my dual 40 dcnf's, Scorpion set up ... I have the alquati manafold with the alquati linkage, the cable is new the peddle seems correct, The problem seems to be that the pedell is not traveling far enough. Can nt understand how this could be :( Any one have any thoughts ?

[DJ]

The Alquati linkage replaces the pivot on the stock linkage assembly with a longer lever. I seem to recall you made this piece for yours. Could this be the problem?

[Allen Lofland]

DJ: No I have the Alquati lever. The triangular piece right?
The funny thing is, the lever and all works fine if you pull the cable far enough, It's just that the pedal is not pulling the cable far enough ? weird !!!

[John Allen]

I have dual 40's on my car and the 'custom' linkage ONLY consists of a welded tab intended for the 'intercarb' balance adjustment and a different rod that connnects the stock Scorpion cable/bellcrank to the rod protruding from one of the carbs (captured by the welded tab). The stock cable pull is more than enough for full throttle.

Very simple in design, much simpler than the descriptions/photos I've seen so far. I'll have to get a photo of it to help in its description.

John

[DJ]

The Alquati linkage isn't as compex as it may sound from our discussion. It's really exactly the same as what John describes except that it has a replacement lever for a longer throw. You should be able to accomplish the same thing by using a shorter rod. (Mine also came with a replacement rod but from what I can tell, it's no different than the stock rod.) I think the longer lever also gives a little better mechanical advantage that helps with all the extra return spring pressure on the duals.

Allen, to answer your pedal travel question, my pedal travel (measured at the top) is about 2.5 inches and I definitely get full throttle plate movement.

This may sound dumb but are you sure your cable doesn't have any slack in it?

[Allen Lofland]

After some more playing around I have discoverd this. My pedal travel is exactly 2 3/8 inches at the top of the pedal. The travel needed from idle to full throttle at the carb linkage is 2 inches. Now JD says his pedal travel is 2 1/2 inches and Jim says his pedal travel is 3 inches.
The limiter on the pedal is the metal around the hole the throttle inserts into hitting the pedal arm, I dont see how this could be different from car to car, BUT what ever. What I need to compare now is the pedal "SET"
If you look at my pedal at idle, the lower part of the bar of the pedal is level with the floor. if there is any extra throw to play with here this bar will not be level but the aft end will be closer to the floor. Now I have my interrior stripped right now so it is easier to see this. I nned some comparison to see if my pedal is being restricted :) Thanks

[Allen Lofland]

I got WIDE OPEN THROTTLE YIPPEEEE VAROOOOOOOOM
Culprit was the pedal travel, seems on my car the little arm on the back of the bedal inside the tunnel was hitting to soon on the return to idle swing. This was probably caused by a shortness in the shaft, anyway I relieved a litle metal in the tunnel and WALA,,WOT for the dual 40 dcnf's. Now we can get on with it. Thanks to all especially DJ's daughter for the help ( ask DJ about that :) Thanks