18 replies to this topic

[NeilR]

I aim to share the car I am making with friends, one of whom is 20cm shorter than me. I had devised a pedal assembly on a sliding tray than was held in place by four spring loaded 'pip' pins though the slide, which held the tray in double shear, it needs around 200mm of movement. The problem is that it seemed a good design on paper, but in practice it is simply too damn hard to get at all of the pins. The other thing we are looking at ATM is a variation of a car seat slide mechanism, but before I go any further has anyone seen an adjustable pedal set on a vehicle and how did it work?

[Lee Nicolle]

Some rally cars etc use them. One I saw had a normal full 'pedal box'  and a couple of sets of holes in the floor with captive nuts. Pipes were flexible type. Maybe just slot the holes and and slide them fore and aft.

First pedal box I made flexed too much and did not inspire confidence so make sure you are bolting it to substansial mounts, not just an alloy floor.

 

These days the Wilwood set ups are cheap enough to not warrant making your own. Nice little cast alloy brackets. Look at their website, a myriad of different styles. AFCO too have quite a range from Wilwood and other suppliers as well. That too will open your eyes and spend an hour or two.

[NeilR]

Thanks for the reply. Part of the reason for wanting a quick and easy to adjust pedal set is that in some events we expect that there may only be a 2-minute turn around between one driver running and the next driver going. So that means driver into pits, get out, change seats, change drivers, tighten belts and pedals and back out to startline.

I have an alloy tilton bias-pedal set currently mounted and I think it is going to be bolted to a 5mm thick 6061 alloy plate. It's the sliding and mounting mechanism that needs to be easy to use. 

[imaginesix]

Theoretically you should only need one pin, which can stop the movement of the pedal box in two dimensions, and a tight fitment of the box between bounding elements of the frame to prevent movemt in the other dimensions. For axample sliding rails, which perform the same function for a seat.

I imagine two pins (for safety's sake) situateds ahead of the footbox (from the driver's perspective) and oriented sideways into elements fixed to the structure on either side of the driver's heels. Given that the forces acting on the pedal are alwas back and down, the floorboard would stop any other motion.

The brake lines could mess things up a bit in the 'tall' configuration, pushing back on the pedal box, so you might need something to remove any tension in the hoses, or if possible locate the two pins above the angle of the brake lines so any pushback from them also acts agaist the floorboard.

Hope that makes sense.

[Greg Locock]

Early Ford Territory had a completely adjustable plastic pedal box. It was electrically powered. I don't know what stroke it had. I think it got cost reduced out at some point, I doubt anyone used it. Shame really, cost a fortune to develop (it is a very crash sensitive area). Off to the scrap yard!

 

http://www.ebay.com....T-/192001201245

[NeilR]

Potential solution here: http://www.ronstan.c...cktraveller.asp

[Charlieman]

200mm (8 inches) shorter in height? That means s/he has shorter legs and most probably shorter arms?

 

Be absolutely honest. How much do you need to change on the car -- seat position, pedal position, wheel position, dashboard controls -- so that you and your co-driver feel comfortable?

[thegforcemaybewithyou]

What about a second pedal set 20cm ahead of the one that's currently in the car. If you have the space it could be permanently in the car under a cover and be brought up if needed. The two pedal sets then could be connected via three rods. Can you imagine what i try to describe?

 

You'll need to be able to have good access to the pedals though, otherwise it will take to long to connect the pedal sets.

[MatsNorway]

Quick release on the steering wheel fixes the different arm length. MOMO, Nardi etc. have same designs with different offsets. Only thing is the position of the shifter. Should be ok to deal with.

[Charlieman]

Quick release on the steering wheel fixes the different arm length. MOMO, Nardi etc. have same designs with different offsets. Only thing is the position of the shifter. Should be ok to deal with.

So move the pedal box -- which we know to be an awkward exercise.

 

And move the steering wheel and column -- easier.

 

But once you have moved the pedals and steering wheel towards the driver, how do you move the dashboard switches?

[NeilR]

different removable seats, wheel and gear mech fixed, sliding pedal box.

[NeilR]

Sorry for my short answer, it was very late. My thinking is that I want to keep the close relationship between the wheel and shift mechanism, so they are essentially fixed, whilst leg/arm length can be accounted for with pedal movement and seat adjustment, the latter being a moulded seat made for the person.

[mariner]

All Marcos Mantula's had an adjustable pedal box mounted on long screw threads, or to be precise a tube one side and a screw thread on the other side.

 

Movement was about 6 inches/150mm. The screw thread had a rod attached which poked out through the dash to a big knob mounted on the dash ( to get a reaction point).

 

Not the lightest system but it worked well. The screw thread is obviously " fail safe" and having it on just one side didn't seem to affect the pedal feel on my Mantula.

 

It was infinitely adjustable over the 150mm so any driver could get his/her setting.

[Fat Boy]

You should be able to do it with different seat inserts. The tallest guy might not fit perfect and the smallest guy might not, either. They should both be reasonably good.

[Bloggsworth]

If a person is 8" shorter, it would be surprising if their legs were anything but about 4" less than those of the taller person, so why do you need 8" movement? Leg length is more important than height, your tall man might have short legs for his height (like me, I'm 6' tall with a 30" inside leg), your short person might have long legs for his height - I would start there.

Edited by Bloggsworth, 05 November 2016 - 15:35.

[Canuck]

My father has short legs relative to his height. When I was in my 20s, we were both 6 feet tall. He wore a 32 leg and I wore a 36. He's still taller than I am when we sit down.

[NeilR]

Bloggs I'm just covering bases as my two teenage boys also want to drive and I want to share the fun ... perhaps my wife will even drive. She's 5' 5"

[Bloggsworth]

Still - Go by leg length not height.

[Fat Boy]

At some point you just have to be reasonable about seat fit. If it's just you in the car, you can be picky. If not, compromise.

 

Years ago, I had Boris Said and a shorter guy(i.e. properly sized race driver) in the same GT car. I was a little worried because of the height difference. Boris folds himself in 1/2 to get into the car. He hits the gas pedal a couple times and says, "Yep, I can get full-throttle, we're good."

 

Aaaaaaaaaaaand, he won the race....