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Hey Guys,

I'm almost to the point where I can run fuel lines and begin wiring to start the car for the first time. But before that I ran into a little problem with the pedals. I'm trying to use the stock miata pedals and hanging them all creates an issue with mounting them with enough space and also problems with the steering column.

Is there a problem with flipping the clutch and brake pedals and then shortening the pedal itself in order to mount on the floor? I included a picture of the rough mockup I was thinking of doing. Obviously the pedals will have to be shortened quite a bit, but will flipping the pedals to mount on the floor cause any problems?

Harry,

Been there done that. You will be buying yourself more headaches, probably wind up spending more $ than biting the bullet and popping for a decent pedal set up. Cutting and welding the Miata pedals is frowned on by the folks that know. A weld on a brake pedal arm is not considered safe.

You're at a point that fitting a purpose built pedal box will be a lot easier than retrofitting one when you find out the inverted Miata pedals just aren't the hot setup.

Trying not to be too preachy but this is exactly what has been keeping my car off the road since last fall. The clutch worked out alright but the brake just sucked.

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Larry in Seattle

What was wrong with it? Was there too much effort needed to push it in?

That is a lot of "junk" sitting under where your heel would be. I did roll my own and might suggest doing that if you are looking to re-invent.

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766

Harry
You are mocking up floor mounted padels with hanger style parts. If you want to use those brackets you should look at making a pedal box and hanging the pedals. Other wise you will have fabricate 75% of all the parts. Also most power brake pedal arm lever ratio will have to be changed from around 3.5 to 1 brake lever ratio to a manual ratio of around 5 to 1 by relocating the push rod clevis hole on the brake pedal lever. I would try building the pedal box so you pedal lever is approximately +12” in overall length. You should ideally try to keep the push rod within a 7 degree angle when setting up the master cylinder location on the pedal box and avoid a pedal lever that goes over center at the end of its travel which would cause a decrease in leverage.
In all probability, you will NOT want power brakes. This will allow you to mount the master cylinder higher giving you a longer brake and clutch pedal pivot point. i.e. better leverage ratio. If you own an Oxy/Acetylene welding torch, you can heat both the brake and cltuch levers so they a straight. Then once you determine your pedal location weld a cut down pipe hang hex with internal threads to the lever. I welded on several pipe hanger hexes’ stack pipe hanger nuts [up/down adj] on the levers and a stud to the back of the padels. This will give you for/aft adjustment the pedals. Depending on the pivot placement of your pedals and the distance from the brake pedal box bulkhead, the push rod may require an extension. If that is the case it may just be easier to fab a completely new push rod from a long bolt for both the clutch and brake cylinders. * You MUST have the same balled end design on the push rod going into the cylinder. If you are on the tall side attach the brake and clutch master cylinder bulk head on the front surface of tube “Q” Vs the back side of the tube so you have a suitable push rod length.
When designing your master brake cylinder and clutch cylinder enclosure box and mounting frame, set the height of face plate for brake master cylinder, so you have about a ½” clearance for the top of the brake reservoir to the hood. This will allow for the longest hanging pedal lever(s) which will make it easier to adjust the lever ratio to your liking.
I would suggest that you use channel stock or weld reinforcing ribs to the mounting face plate used for both the clutch and brake master cylinders mounting plate(s) to reduce any deflection in the mounting surface under heavy braking. The master cylinder mounting plate should be at a minimum of .100” or thicker, plus localized reinforcing in the mount area or an additional reinforcing rib(s) welded to the mounting plate surface.
Note: both the brake and clutch pedal lever clevis holes can be move up or down on the pedal lever within about 5 degree swing angle to accommodate some changing of the pedal ratio if required to reduce the braking effort.
Dave W

I used the complete Miata setup, including master cylinders. I'll have to look for pictures during assembly, they might be on a memory stick or on the old camera but here are a couple of the finished assembly.


I had to do some trimming of the mounts and I tilted the clutch assembly slightly to get things to fit. I'm happy with how it turned out, using the stock parts means the clutch and brakes feel just like they should. I did not use the brake booster from the power brakes and it is not necessary. I did not change the lengths of the pedals or the ratio.

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My car viewtopic.php?f=37&t=16434
1930s Style Sports Car viewtopic.php?f=36&t=16888

Thanks guys for the thorough responses! I'll try going back to it and try to hang them first. If that doesn't work with my space issues then i'll have to go about making my own pedals. Dave, that was a lot of information that I did not know about before thanks for that

Harry,

I thought cutting up the Miata pedal box was the thing to do. First the bracket doesn't sit flat on the floor. The hanging pedal was to long to fit in a floor mount and was shortened. Look close and you can see 2 welds on the arm which I was told much later is a no no. The ratio here is right at 2.5 to 1 with a short pedal. Pushing on the pedal was like pushing against a wall. Took a whole lot of pressure to stop the car and almost impossible lock the brakes.

Because all the plumbing was already in place I really didn't want to move the master cylinder. I made a new bracket, a neighbor gave me a Spitfire pedal that would fit with a little work. I now have 5.5 to 1 ratio and a decent pedal feel. Haven't had a chance to drive it after the fix (doing some exhaust mods to quiet it down some) but it has to be better.

Old:


New:


Cheers

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Larry in Seattle

I didn't use any miata pedals, but thought about modifying the Toyota pedals I had to a floor mount. I decided against it in the end and instead built a reverse swing pedal box using modified Corolla pedals. I cut the pedals shorter, then drilled them and welded in bushing tubes. I made the bracket assembly to hold the pedal pivot rod and the master cylinders from 1/8" sheet welded together. It worked good for getting the master cylinders away from my exhaust. Something like that might work for your car too.





Kristian

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V6 in a book frame build. Now registered.
viewtopic.php?f=35&t=7587
viewtopic.php?f=33&t=18172

I like Kristian's set up. Where did you get that support bearing on the steering. I need one of those.

Cheers

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Larry in Seattle

That's what I was afraid of. I figured the ratio would make it so the pedal is too hard to push. I guess I will mount my steering column where it needs to be and see if I can trim enough out of the brackets to hang the miata pedals. That way it'll feel right to push the pedals and save me some money.

Thanks guys!

Thanks. The bearing was either from Speedway or Summit, I can't remember which, but they both carry the same thing. As far as the pedals, I shortened mine up but kept the original pedal ratio. You can change the ratio to anything you want, just drill the hole for the pushrod in the right spot.
Kristian

_________________
V6 in a book frame build. Now registered.
viewtopic.php?f=35&t=7587
viewtopic.php?f=33&t=18172

I found a few pictures from when I was building. Here is a weldment that holds the bracket and master.

The bracket welded

In place

another view

There is more structure that is part of the steering wheel support that I don't have pictures of. It ties things together a bit better.

_________________
My car viewtopic.php?f=37&t=16434
1930s Style Sports Car viewtopic.php?f=36&t=16888

thanks that'll be a big help for me. Just gotta find a bolt to make the pushrod now and I should be all set.

I tore apart the power brake ass'y, I used both the pedal piece and the pushrod from inside the PB ass'y. I welded a rod between both pieces rather than making an entire pushrod. No problem trying to match the radius of the tip that way.

_________________
Chuck.

“Any suspension will work if you don’t let it.” - Colin Chapman

Visit my ongoing MGB Rustoration log: over HERE

Or my Wankel powered Locost log : over HERE

And don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766