55.2-59 gas pedal height - The 1947 - Present Chevrolet & GMC Truck Message Board Network

popeyestruck · 07-22-2024, 03:09 PM

How close to the floor should the gas pedal be when floored? With all the new linkages I've put in I may need to shorten the gas pedal rod

**mr48chev** · 07-22-2024, 04:01 PM

How far it goes down will depend on how much travel it takes to have the throttle wide open. Then you factor in the ratios of the bell cranks and throttle arm. If the throttle is wide open when the pedal is at that spot life is good, if that is all the travel you get and the throttle isn't wide open something will need to be adjusted. A guy could put and adjustable throttle stop under the pedal and have a solid stop point when the throttle blades are wide open or for "that's fast enough".

popeyestruck · 07-22-2024, 05:53 PM

Quote:

Originally Posted by mr48chev

How far it goes down will depend on how much travel it takes to have the throttle wide open. Then you factor in the ratios of the bell cranks and throttle arm. If the throttle is wide open when the pedal is at that spot life is good, if that is all the travel you get and the throttle isn't wide open something will need to be adjusted. A guy could put and adjustable throttle stop under the pedal and have a solid stop point when the throttle blades are wide open or for "that's fast enough".

Wide open throttle has the pedal a couple inches off the floor. I Could add a stop there but it seems pretty high and not a lot of angle on the pedal. How far off the floor should it be at wide open throttle?

dsraven · 07-23-2024, 01:29 AM

it is kinda up to you but don't forget to factor in carpet and underlay if thats your plan.
lots of modern vehicle use styrofoam style blocks that raise or level out the floor over uneven sections. you could do that too if you feel right about the pedal where it is. remember to sit in the seat and check the angle of the foot when pressing the accel pedal. nothing worse than a wrong angle that results in a sore calf or shin muscles or an ankle that is sore after a long drive.

popeyestruck · 07-23-2024, 04:14 AM

Quote:

Originally Posted by dsraven

it is kinda up to you but don't forget to factor in carpet and underlay if thats your plan.
lots of modern vehicle use styrofoam style blocks that raise or level out the floor over uneven sections. you could do that too if you feel right about the pedal where it is. remember to sit in the seat and check the angle of the foot when pressing the accel pedal. nothing worse than a wrong angle that results in a sore calf or shin muscles or an ankle that is sore after a long drive.

Yeah i was just trying to get an idea if originally the pedal went all the way to the floor to get a general idea how much to shorten the rod then fine tune from there. Attached is photos of where I am. Brake pedal isn't screwed in so it will be about an inch lower. 2nd photo is the gas pedal floored. Should my gas pedal be that far from the floor?

leegreen · 07-23-2024, 09:53 AM

What I'd do is sit on the seat or something of similar height and make sure the pedal is comfortable under my foot at idle. It looks to my eye that it is too upright and you'd be flexing your toe/foot upwards more than is comfortable.

WOT will probably be close to parallel to the toeboard, you are only WOT for a few seconds at a time so if it is a bit of a toe curl to hold it down that is no big deal

jwhotrod · 07-23-2024, 10:46 AM

if you are using a cable type pedal, full throttle should be against the finished floor. if you don't do that it will pull the "ball" off the end of the cable. pedal and rod are not so fussy, it depends on how your bell crank and rods travel.

nvrdone · 07-23-2024, 07:05 PM

OK, Here's a simple answer for you. At WOT the nose of my pedal is 1" off the floor. the back of the pedal is just touching the spacer under the pedal. This is with full insulation and carpet. My linkage is a bell crank with threaded rod on both sides. The upper arm is 5" center to center and the lower arm is 4" center to center. Your dimensions may vary.
Hope this helps.

nvrdone · 07-23-2024, 07:09 PM

I forgot to ask - how far from the floor is the nose of your pedal at WOT? You may need to shorten the rod from the pedal to the bell crank to get a comfortable angle.

popeyestruck · 07-24-2024, 04:16 AM

Quote:

Originally Posted by nvrdone

I forgot to ask - how far from the floor is the nose of your pedal at WOT? You may need to shorten the rod from the pedal to the bell crank to get a comfortable angle.

Its over 6 inches . My next step is shortening the rod. Thanks for the simple answer

**mr48chev** · 07-24-2024, 02:03 PM

The main thing is that the pedal position has to be comfortable at low and highway speeds. Set it up for the shoes/footwear that you will do most of your driving especially on road trips in. Comfort for your leg and foot that you work the throttle with is one of the most important things in the build if you intend to do a lot of driving.

dsraven · 07-25-2024, 10:54 AM

I'm with mr48, leegreen and nvrdone on this one. put the seat in or use something of the same height for mock up (the seat is best because you get the correct feel), then sit in there and ensure the pedal is at a good angle for driving. the distance to the firewall is sorta irrelevant as long as you can acjieve full throttle before bottomoing out the pedal on the floor, firewall, floor mat etc. once done this then build a pedal stopper so, like nvrdone says, the linkage and carb throttle shaft lever dont take the full hit of the mechanical advantage given by the set up. if you had a cable operated linkage this would be a very important step. when all done ensure you install a return spring that will do the job but not overdo the job. otherwise your leg will pay the price.
I once had a boss who would drive into the shop, announce he had a problem with his truck and i needed to drop everything in order to get his truck running perfectly. this got old after a few times of "its not running right, I dunno why, I was just driving in to work" and me finding he had floated the valves, bent pushrods etc, again. anyway, long story short, I installed a screen door return spring on his linkage. it was awhile till he came back but when he did he asked if I still had the original throttle spring. haha
I also installed a golf ball under his seat so the "funny noise going around corners" complaint was an easy (but took a long time to diagnose) fix.

popeyestruck · 07-26-2024, 03:08 AM

I got everything set up with the linkage and it works great today I'll set a stop and drill the holes for the heal of the pedal

popeyestruck · 07-26-2024, 08:29 AM

Linkage works good until I add the rod that connects the pedal to bellcrank. I'm getting binding and the heal of the pedal moves forward as you press down. The geometry is off. This is the rod that came with it . It was bent into almost an s shape to get it to work and the peday had broke of the floorboard . Ive straighten it some and threaded the end to adjust for the extra travel straightening gives it. What should the rod look like? Should it be straight so the bellcrank get pushed back horizontally. I'm thinking I'll heat it up and take out the bends until it looks like the manual then Ill need to thread more of it since it get longer as it get straighter. Any ideas? At this point I'm almost ready to buy a cable driven pedal and be done with it. Last question is any recommendations for a cable pedal assembly?

07-22-2024, 03:09 PM	#1
popeyestruck Registered User Join Date: May 2022 Location: Longwood 59 chevy Posts: 291	gas pedal height How close to the floor should the gas pedal be when floored? With all the new linkages I've put in I may need to shorten the gas pedal rod

07-22-2024, 04:01 PM	#2
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,639	Re: gas pedal height How far it goes down will depend on how much travel it takes to have the throttle wide open. Then you factor in the ratios of the bell cranks and throttle arm. If the throttle is wide open when the pedal is at that spot life is good, if that is all the travel you get and the throttle isn't wide open something will need to be adjusted. A guy could put and adjustable throttle stop under the pedal and have a solid stop point when the throttle blades are wide open or for "that's fast enough". __________________ Founding member of the too many projects, too little time and money club. My ongoing truck projects: 48 Chev 3100 that will run a 292 Six. 71 GMC 2500 that is getting a Cad 500 transplant. 77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.

07-23-2024, 01:29 AM	#4
dsraven Registered User Join Date: Nov 2010 Location: calgary alberta Posts: 8,203	Re: gas pedal height it is kinda up to you but don't forget to factor in carpet and underlay if thats your plan. lots of modern vehicle use styrofoam style blocks that raise or level out the floor over uneven sections. you could do that too if you feel right about the pedal where it is. remember to sit in the seat and check the angle of the foot when pressing the accel pedal. nothing worse than a wrong angle that results in a sore calf or shin muscles or an ankle that is sore after a long drive.

07-23-2024, 09:53 AM	#6
leegreen Registered User Join Date: Mar 2022 Location: Surrey BC Posts: 888	Re: gas pedal height What I'd do is sit on the seat or something of similar height and make sure the pedal is comfortable under my foot at idle. It looks to my eye that it is too upright and you'd be flexing your toe/foot upwards more than is comfortable. WOT will probably be close to parallel to the toeboard, you are only WOT for a few seconds at a time so if it is a bit of a toe curl to hold it down that is no big deal

07-23-2024, 10:46 AM	#7
jwhotrod Registered User Join Date: Oct 2018 Location: DeKalb, IL Posts: 157	Re: gas pedal height if you are using a cable type pedal, full throttle should be against the finished floor. if you don't do that it will pull the "ball" off the end of the cable. pedal and rod are not so fussy, it depends on how your bell crank and rods travel.

07-23-2024, 07:05 PM	#8
nvrdone Registered User Join Date: Dec 2011 Location: Moxee WA Posts: 1,479	Re: gas pedal height OK, Here's a simple answer for you. At WOT the nose of my pedal is 1" off the floor. the back of the pedal is just touching the spacer under the pedal. This is with full insulation and carpet. My linkage is a bell crank with threaded rod on both sides. The upper arm is 5" center to center and the lower arm is 4" center to center. Your dimensions may vary. Hope this helps. __________________ 49 chevy 3100 3 window. 327 / m21 4 spd, 12 bolt w/ 3:55's Bought in 1973 for $235.00. Had it longer than my wife & Kids!!

07-23-2024, 07:09 PM	#9
nvrdone Registered User Join Date: Dec 2011 Location: Moxee WA Posts: 1,479	Re: gas pedal height I forgot to ask - how far from the floor is the nose of your pedal at WOT? You may need to shorten the rod from the pedal to the bell crank to get a comfortable angle. __________________ 49 chevy 3100 3 window. 327 / m21 4 spd, 12 bolt w/ 3:55's Bought in 1973 for $235.00. Had it longer than my wife & Kids!!

07-24-2024, 02:03 PM	#11
mr48chev Registered User Join Date: Jul 2007 Location: Toppenish, WA Posts: 15,639	Re: gas pedal height The main thing is that the pedal position has to be comfortable at low and highway speeds. Set it up for the shoes/footwear that you will do most of your driving especially on road trips in. Comfort for your leg and foot that you work the throttle with is one of the most important things in the build if you intend to do a lot of driving. __________________ Founding member of the too many projects, too little time and money club. My ongoing truck projects: 48 Chev 3100 that will run a 292 Six. 71 GMC 2500 that is getting a Cad 500 transplant. 77 C 30 dualie, 454, 4 speed with a 10 foot flatbed and hoist. It does the heavy work and hauls the projects around.

07-25-2024, 10:54 AM	#12
dsraven Registered User Join Date: Nov 2010 Location: calgary alberta Posts: 8,203	Re: gas pedal height I'm with mr48, leegreen and nvrdone on this one. put the seat in or use something of the same height for mock up (the seat is best because you get the correct feel), then sit in there and ensure the pedal is at a good angle for driving. the distance to the firewall is sorta irrelevant as long as you can acjieve full throttle before bottomoing out the pedal on the floor, firewall, floor mat etc. once done this then build a pedal stopper so, like nvrdone says, the linkage and carb throttle shaft lever dont take the full hit of the mechanical advantage given by the set up. if you had a cable operated linkage this would be a very important step. when all done ensure you install a return spring that will do the job but not overdo the job. otherwise your leg will pay the price. I once had a boss who would drive into the shop, announce he had a problem with his truck and i needed to drop everything in order to get his truck running perfectly. this got old after a few times of "its not running right, I dunno why, I was just driving in to work" and me finding he had floated the valves, bent pushrods etc, again. anyway, long story short, I installed a screen door return spring on his linkage. it was awhile till he came back but when he did he asked if I still had the original throttle spring. haha I also installed a golf ball under his seat so the "funny noise going around corners" complaint was an easy (but took a long time to diagnose) fix.

07-26-2024, 03:08 AM	#13
popeyestruck Registered User Join Date: May 2022 Location: Longwood 59 chevy Posts: 291	Re: gas pedal height I got everything set up with the linkage and it works great today I'll set a stop and drill the holes for the heal of the pedal

07-26-2024, 08:29 AM	#14
popeyestruck Registered User Join Date: May 2022 Location: Longwood 59 chevy Posts: 291	Re: gas pedal height Linkage works good until I add the rod that connects the pedal to bellcrank. I'm getting binding and the heal of the pedal moves forward as you press down. The geometry is off. This is the rod that came with it . It was bent into almost an s shape to get it to work and the peday had broke of the floorboard . Ive straighten it some and threaded the end to adjust for the extra travel straightening gives it. What should the rod look like? Should it be straight so the bellcrank get pushed back horizontally. I'm thinking I'll heat it up and take out the bends until it looks like the manual then Ill need to thread more of it since it get longer as it get straighter. Any ideas? At this point I'm almost ready to buy a cable driven pedal and be done with it. Last question is any recommendations for a cable pedal assembly? Attached Images



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