adjustable pedal mount

Davidmgbv8

Supporter
Has anyone used one of these in their GT40? It is similar to the RCR version. What are your thoughts?
1668027716560.png
 

Davidmgbv8

Supporter
So I got the adjustable pedal mount in and I can make the pedal assembly fit. have to add more metal to floor board to allow this to bolt down.
Has any one used this style or the RCR style and what are the thoughts?

Thanks
 

Ian Anderson

Lifetime Supporter
How adjustable is that? Do you have to dive under the steering wheel with spanner’s etc?

if so at this stage mount it on chair runners so adjustment is without tools spanner’s and diving under the dash.

Ian
 

Devin

Supporter
Do you think the assembly will be stable enough without movement when pressing the clutch pedal? The brake pedal seems to be centered and accelerator shouldn’t receive too much lateral torque.
 

Howard Jones

Supporter
I would have to see how it's mounted at the least. From what is in the picture I wouldn't use it if it was given to me. Remember the brake peddle gives you a mechanical advantage of 6 to one. It is pretty easy to apply 100 pounds to the peddle with a relatively moderately aggressive brake application. Easy 1000 pounds in a panic stop.

At the very least the area between the chassis tubing should be filled in completely with a steel plate in the area where the mount will be attached. I would use 1/8" thick 4140 for that and maybe add a couple of additional chassis members across the area as well.

Then there is the adjustable assembly. If it has any movement in it when "locked" in the desired position then...............well it would not be for me. I also think that the stationary fixed plate on the bottom with slots in it needs to be thicker, 1/4" 4140, and quite a bit larger, at least as wide and long as the peddle mount plate. The top plate that is attached to the peddle box also needs to be as wide and long as the peddle box itself and utilize all the mounting bolts, especially in the corners. Place the slots along the perimeter. That "pin" should be made from a 3/8 grade 8 bolt minimum. If I made one it would be 1/2 inch and I would try to figure out a way to make it redundant (two pins spread out and not in line with one of the pedals). I also don't think they penetrate the fixed plate enough, It looks like a 1/4 inch or so. I would do at least the depth of the chassis rails and shield them from the bottom (roadside) with another plate. I see a lot to be improved here.

That's my free advice.

I tried to use a 1/8 thick 6061 aluminum plate with a series of holes in it to provide adjustability in the same way as this unit does but in a more permanent but adjustable manner. It flexed so much that I took it out immediately and bolted the peddle box through the floor with 2-inch diameter steel heavy washers on the other side with 4 3/8 grade 8 bolts.

My personal opinion is (without seeing it in person and trying it in use) that it's not stiff enough. Especially if it's made out of aluminum. If it's high-grade stiff steel.......... may be safe enough and usable in a street car but not in an extreme-performance high-powered car with sticky tires and big brakes. Then ...............if it fails........where does that put you. In the fence? Think about an emergency full brake effort stop with the car and you or others' lives on the line..............and the locking pin breaks, slips, etc.

This didn't work for me in my car. It felt like cardboard when pushing fairly hard on the brakes.

Adjustable pedals are good idea but they cant be under-engineered. Kinda like seat belt mounts. They must be done right. I call this category of parts itelkillyaparts.
 

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Neil

Supporter
I would have to see how it's mounted at the least. From what is in the picture I wouldn't use it if it was given to me. Remember the brake peddle gives you a mechanical advantage of 6 to one. It is pretty easy to apply 100 pounds to the peddle with a relatively moderately aggressive brake application. Easy 1000 pounds in a panic stop.

At the very least the area between the chassis tubing should be filled in completely with a steel plate in the area where the mount will be attached. I would use 1/8" thick 4140 for that and maybe add a couple of additional chassis members across the area as well.

Then there is the adjustable assembly. If it has any movement in it when "locked" in the desired position then...............well it would not be for me. I also think that the stationary fixed plate on the bottom with slots in it needs to be thicker, 1/4" 4140, and quite a bit larger, at least as wide and long as the peddle mount plate. The top plate that is attached to the peddle box also needs to be as wide and long as the peddle box itself and utilize all the mounting bolts, especially in the corners. Place the slots along the perimeter. That "pin" should be made from a 3/8 grade 8 bolt minimum. If I made one it would be 1/2 inch and I would try to figure out a way to make it redundant (two pins spread out and not in line with one of the pedals). I also don't think they penetrate the fixed plate enough, It looks like a 1/4 inch or so. I would do at least the depth of the chassis rails and shield them from the bottom (roadside) with another plate. I see a lot to be improved here.

That's my free advice.

I tried to use a 1/8 thick 6061 aluminum plate with a series of holes in it to provide adjustability in the same way as this unit does but in a more permanent but adjustable manner. It flexed so much that I took it out immediately and bolted the peddle box through the floor with 2-inch diameter steel heavy washers on the other side with 4 3/8 grade 8 bolts.

My personal opinion is (without seeing it in person and trying it in use) that it's not stiff enough. Especially if it's made out of aluminum. If it's high-grade stiff steel.......... may be safe enough and usable in a street car but not in an extreme-performance high-powered car with sticky tires and big brakes. Then ...............if it fails........where does that put you. In the fence? Think about an emergency full brake effort stop with the car and you or others' lives on the line..............and the locking pin breaks, slips, etc.

This didn't work for me in my car. It felt like cardboard when pushing fairly hard on the brakes.

Adjustable pedals are good idea but they cant be under-engineered. Kinda like seat belt mounts. They must be done right. I call this category of parts itelkillyaparts.
4130N will be much easier to find than 4140. Welds better, too.
 

Davidmgbv8

Supporter
I would have to see how it's mounted at the least. From what is in the picture I wouldn't use it if it was given to me. Remember the brake peddle gives you a mechanical advantage of 6 to one. It is pretty easy to apply 100 pounds to the peddle with a relatively moderately aggressive brake application. Easy 1000 pounds in a panic stop.

At the very least the area between the chassis tubing should be filled in completely with a steel plate in the area where the mount will be attached. I would use 1/8" thick 4140 for that and maybe add a couple of additional chassis members across the area as well.

Then there is the adjustable assembly. If it has any movement in it when "locked" in the desired position then...............well it would not be for me. I also think that the stationary fixed plate on the bottom with slots in it needs to be thicker, 1/4" 4140, and quite a bit larger, at least as wide and long as the peddle mount plate. The top plate that is attached to the peddle box also needs to be as wide and long as the peddle box itself and utilize all the mounting bolts, especially in the corners. Place the slots along the perimeter. That "pin" should be made from a 3/8 grade 8 bolt minimum. If I made one it would be 1/2 inch and I would try to figure out a way to make it redundant (two pins spread out and not in line with one of the pedals). I also don't think they penetrate the fixed plate enough, It looks like a 1/4 inch or so. I would do at least the depth of the chassis rails and shield them from the bottom (roadside) with another plate. I see a lot to be improved here.

That's my free advice.

I tried to use a 1/8 thick 6061 aluminum plate with a series of holes in it to provide adjustability in the same way as this unit does but in a more permanent but adjustable manner. It flexed so much that I took it out immediately and bolted the peddle box through the floor with 2-inch diameter steel heavy washers on the other side with 4 3/8 grade 8 bolts.

My personal opinion is (without seeing it in person and trying it in use) that it's not stiff enough. Especially if it's made out of aluminum. If it's high-grade stiff steel.......... may be safe enough and usable in a street car but not in an extreme-performance high-powered car with sticky tires and big brakes. Then ...............if it fails........where does that put you. In the fence? Think about an emergency full brake effort stop with the car and you or others' lives on the line..............and the locking pin breaks, slips, etc.

This didn't work for me in my car. It felt like cardboard when pushing fairly hard on the brakes.

Adjustable pedals are good idea but they cant be under-engineered. Kinda like seat belt mounts. They must be done right. I call this category of parts itelkillyaparts.
Thanks for the insight, I will mount up and give a test.
 

Neil

Supporter
David, here is how I fabricated my pedal assembly. It is riveted to the steel chassis tubes.
 

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  • Pedal- Clutch.jpg
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JimmyMac

Lifetime Supporter
David,

Back in the day I had an idea of cutting a pedal box out of a vertical aluminium beam section.
With a decent welder to assemble a base and add fastener bosses it would look pretty good.
One would get a floor mounted pedal set but also fixed to the top of the scuttle.

A short section of 6061 beam with a 5" web would do the trick and look similar to the original casting if you cut the flanges and web to profile.


Castings 004.jpeg
 
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