Throttle ratio

[ellis8500]

OK, another question from a new guy to the experts. What is a good throttle pedal ratio for mild street manners? By ratio I mean how far do you have to move the pedal to achieve full throttle. If the ratio is too low, not a lot of pedal movement, then it will be more difficult to move forward/reverse at slow speeds. The pedal will be too sensitive. Too much pedal travel and it will seem like ya have to almost floor it to get it to go. My truck has 2 inches of travel. My truck also weighs 4,200 lbs and has about 240 ft-lbs of torque. So I'm wondering how that same setup would feel in a 2,000 lb car with 330 ft-lbs.

My carb requires 1-1/4 in linear travel to full throttle. 2 in. of throttle would be a ratio of 1.6:1. Would 1.7, 1.8 or even 2 to 1 be more suitable for a 27T? So if some of you would, check the pedal travel of your throttle and relate it to how the car behaves in normal street driving. Tell me if it's "Like a rocket with just a push", "Like a production sedan" or "A slug 'til I mash it good". I'm sure this would be some good information for others new to the hobby.

Thanks guys. I always appreciate the good advice I get here. I'm at the point in my build where it's ready to take it all apart and start painting.

Bill
St. Louis, MO

 

[Screaming Metal]

Mr. Bill, now, don't want you to take me as a smart-ass or anything....which some of the racing community seems to do on occassion.

I'll put it to you like I'm talking to the driver. 'WHAT MAKES YOU HAPPY?'

Maybe Ted or Mike or Putz can give you some insight....I just build the machines. I Guess alot of it is personal feel...my 392 has about 3 inches...and full throttle is achieved at 2 7/8's.

Usually when we build a new car, and it has a super kick booty motor in it...idon't worry about setting the throttle up until thedriver is ready to drive....then its all according to this feel, likes and dislikes.

 

[putz]

One of the factors to be figured in is the shape of the area where throttle is to be mounted if the ratio is wrong then you might hit the floor with the pedal before full throttle. What I put in mine nothing against RPm products I have many of them on my car. But I put a pedal that the index can be changed. What I mean is the angle that the bottom of the pedal is at compared to the top pulling the cable angle can be changed easily. When I first got mine the throttle was !/2 when hitting the floor a simple angle change on the splines wala.It also has 3 hole for changing the ratio.
my throttle pedal link

 

[EX JUNK]

OK, another question from a new guy to the experts. What is a good throttle pedal ratio for mild street manners? By ratio I mean how far do you have to move the pedal to achieve full throttle. If the ratio is too low, not a lot of pedal movement, then it will be more difficult to move forward/reverse at slow speeds. The pedal will be too sensitive. Too much pedal travel and it will seem like ya have to almost floor it to get it to go. My truck has 2 inches of travel. My truck also weighs 4,200 lbs and has about 240 ft-lbs of torque. So I'm wondering how that same setup would feel in a 2,000 lb car with 330 ft-lbs.

My carb requires 1-1/4 in linear travel to full throttle. 2 in. of throttle would be a ratio of 1.6:1. Would 1.7, 1.8 or even 2 to 1 be more suitable for a 27T? So if some of you would, check the pedal travel of your throttle and relate it to how the car behaves in normal street driving. Tell me if it's "Like a rocket with just a push", "Like a production sedan" or "A slug 'til I mash it good". I'm sure this would be some good information for others new to the hobby.

Thanks guys. I always appreciate the good advice I get here. I'm at the point in my build where it's ready to take it all apart and start painting.

Bill
St. Louis, MO

Mr. Bill, on my car the arm on the carb is 1 1/4" center to center on the pivot points and the arm on my accelerator pedal is 5" center to center and the arm on the foot or "spoon" is 5" also. The arm of the carb travels 1 1/2" and the foot pedal travels 1 1/2", as close as I can measure. I am using a Lokar throttle assembly and the car is VERY streetable and comfortable. I hope that this will answer your question.

Jim