Getting the pedals closer in line for foot work., Want to lower the brake pedal... Options

[peteinjp]

So for me the brake and gas pedals are too far off from each other in terms of height to make quick movements from the gas to brake. I have to lift my foot entirely up and back...

I am thinking of making a thicker stop to keep the brake pedal lower (adjusting the push rod accordingly of course) but that lessens the travel of the master. It may still be plenty (21mm.) I could add a spacer under the master to compensate if needed.

OR I could just take a bit out of the pedal as the top portion is almost in line with the direction of travel it would have no impact in terms of pedal ratio.

I don't have an issue with the height of the clutch pedal because its basically in line with the dead pedal/firewall area.

What have you guys done to get the pedals in an ideal location- not including Tilton etc.... not going that far.

Pete

[bdstone914]

So for me the brake and gas pedals are too far off from each other in terms of height to make quick movements from the gas to brake. I have to lift my foot entirely up and back...

I am thinking of making a thicker stop to keep the brake pedal lower (adjusting the push rod accordingly of course) but that lessens the travel of the master. It may still be plenty (21mm.) I could add a spacer under the master to compensate if needed.

OR I could just take a bit out of the pedal as the top portion is almost in line with the direction of travel it would have no impact in terms of pedal ratio.

I don't have an issue with the height of the clutch pedal because its basically in line with the dead pedal/firewall area.

What have you guys done to get the pedals in an ideal location- not including Tilton etc.... not going that far.

Pete

If you shorten the brake pedal it will increase the pressure you need to apply an the lever arm is shorter.
You may have some room the space the master clyinder but will need to grind out the bolts in the pedal set and replace with longer bolts. You may try shortening the brake rod and making a different return stop so the brake pedal stay further down.

[r_towle]

Add something to the top of the gas pedal?
I have big feet so I never had an issue with this, but I have the other issue of having big feet in the Porsches….I need to choose my shoes carefully when I’m driving

[yeahmag]

Adding an aftermarket pedal with heel/toe extensions may help:

https://www.rennline.com/rennline-gas-pedal...sku=P44%20BLACK

[fixer34]

Screw a 1-1/2-2" thick piece of wood to the gas pedal. Use pine or maybe balsa so it doesn't add a lot of weight. Also easy to remove if you change your mind.

But also consider- you are looking at the gas to brake transition. What about brake to gas? Do you want to pull your foot all the way back so you can move to the gas pedal. Sometimes it is easier to just slide your foot off the brake while depressed on to the gas.
And clutch with toe/heel brake/gas may be a little interesting.

[peteinjp]

If you shorten the brake pedal it will increase the pressure you need to apply an the lever arm is shorter.
You may have some room the space the master clyinder but will need to grind out the bolts in the pedal set and replace with longer bolts. You may try shortening the brake rod and making a different return stop so the brake pedal stay further down.

All true for sure. Might just check the travel and if there is more than enough to lockup the brakes then make a longer rest stop and re-adjust the clearance. If that is not enough shorten the rod. Probably wouldn't take much.

Add something to the top of the gas pedal?
I have big feet so I never had an issue with this, but I have the other issue of having big feet in the Porsches….I need to choose my shoes carefully when I’m driving

Size 13 wide here- no I dont drive with crocs as in the pic below BTW. I recommend looking into Joe Nimble trekking shoes if you have them in your area. Great balance of being roomy but not too bulky.

Adding an aftermarket pedal with heel/toe extensions may help:

https://www.rennline.com/rennline-gas-pedal...sku=P44%20BLACK

It's more of an issue with the height of the pedals. Cool stuff for sure though!

Screw a 1-1/2-2" thick piece of wood to the gas pedal. Use pine or maybe balsa so it doesn't add a lot of weight. Also easy to remove if you change your mind.

But also consider- you are looking at the gas to brake transition. What about brake to gas? Do you want to pull your foot all the way back so you can move to the gas pedal. Sometimes it is easier to just slide your foot off the brake while depressed on to the gas.
And clutch with toe/heel brake/gas may be a little interesting.

For me the best arrangement is such that when I'm hard on the brakes the go pedal is right there at the same level. I could still drop the brake pedal down a bit and to a nice blip and transition tot he throttle. Pics will explain. In the current configuration I find my foot actually getting hung up on the back side of the brake pedal a bit. Too much of a gap for heel toe and awkward getting up and around the brake pedal when coming from the gas. My foot is not depressing the accel pedal at all:




I realize I can just increase the thickness of the gas pedal but with long legs I'd love to lower the brake instead. Why do I alway prefer the hard way?? Ha!

Pete

[peteinjp]

It’s a bit hard to see, but I had a little piece of hose to the brake pedal rest rod and adjusted to push rod accordingly.





I’ll report back after I good drive.

[infraredcalvin]

I asked about this issue once when originally working on my racing license, coach basically told me, every car is going to be a bit different, especially when you drive someone else’s car. Figure it out, make the adjustments with your feet, roll them, pivot them, move the positions you touch the pedals, with your heel, the ball of your foot or somewhere in between, sometimes even the toes… learn to drive what you’ve got, and you'll be more versatile jumping in another car.

IMO the pedal cluster in the 914 (early porsche) is one of the easiest to learn/master heel toe…. My 914s are each slightly different, as well as my 930, takes a sec to adapt when jumping from one to the other, but i haven’t made any adjustments to try and match them.

Remember, it’s an old car, sometimes things shouldn’t happen as fast is it could in a new car…

[Superhawk996]

(IMG:style_emoticons/default/agree.gif)

Good advice there. IMHO my 914 was more of a true heel & toe maneuver that requires me to pivot up at the ball of my foot and then my heel was right where it needed to be over the gas pedal.

I’m sure technique has to be varied based on the physical size of the driver.

Keep in mind that by reducing the stroke of the master cylinder, you have less displacement. May or may not matter based on the size of the master cylinder in relation to the caliper and pad displacement needs and the temperature they are running at. You’ll likely never need that last few CC’s of fluid displacement until the brakes are hot and faded. But when you need it, you need it.

Personally, I’d tweak the throttle pedal and its push rod before I did anything that would reduce brake displacement. The only thing worse than a car that won’t go, is one that wont stop.

[emerygt350]

I found it was pretty good on the track, you are jamming that brake really hard while blipping the throttle to down shift which puts the throttle right about where it needs to be. At least in my car. In a lighter braking street situation I do find a harder reach but it doesn't really matter in that situation.

[peteinjp]

All good points and well taken. On the track it would be just about right. My 964 is similar- with hard braking the pedal accelerator pedal is right there.

But on back roads I'm just going for smooth transitions rather than 10ths. When I do heel/toe I have to roll my foot off the brake to a degree where I get worried about it slipping off and that's uncomfortable.

The master is 21mm and there looks to be plenty of room left with the pedal mashed down hard. I haven't reduced the stoke of th4pater per say but may have reduced the stroke of the brake pedal itself.

Good point about faded and I'll keep that in mind. I have not decided that this is the answer yet and will be trying it out with all this in mind.

I have big feet so its not actually heel and toe- more like ball of the foot on the brake and pinky toe/ right edge of my foot on the gas kinda thing. Also with the stock steering wheel and shifter there is NO wiggle room for my right leg in 2nd and 3rd. Even with the Momo and Rennshifter installed though its still not quite right.

One thing I noticed is that even with the brake pedal lower the gas is a bit far off. My next thing to try is a pedal with less of a sidewards angle to it. I used the 935 style unit from rebel racing in my 964 and liked it so I might try moving that over to the 914. But I like the stock look in this car so I may make print my own.

[Superhawk996]

I don’t know the details of your brake situation and/or where the front vs rear bias is at. I was assuming you were probably at 19mm master cylinder as so many cars are now if for no other reason than the fact that the 17mm stock master is no longer available.

However, it may be possible that the 21mm master cylinder is working against you by providing too much fluid displacement. It is conceivable that a 19mm master would reduce pedal force and increase pedal travel to the point that you would be happier. If you have calipers that demand a lot of displacement it’s also possible that the move to a 19mm master could leave you without displacement in reserve. The details matter.

Unfortunately the way most cars end up with modified brakes it’s sort of a “well this worked for so & so” or “ this worked on the Boxter” so it’ll be OK. Very few people have done either the basic engineering or the trial and error testing & tuning to know if they have an optimal system for their intended purposes. It’s not easy to do that testing on public roads, and it’s easy to lose sight of edge cases that matter (hot brakes, balance on wet pavement when cornering, brake balance vs load in front or rear trunk, etc.)

Long way to say that the system as built may not be right for you.

There a multiple ways to achieve the goal as you noted.

[peteinjp]

I don’t know the details of your brake situation and/or where the front vs rear bias is at. I was assuming you were probably at 19mm master cylinder as so many cars are now if for no other reason than the fact that the 17mm stock master is no longer available.

However, it may be possible that the 21mm master cylinder is working against you by providing too much fluid displacement. It is conceivable that a 19mm master would reduce pedal force and increase pedal travel to the point that you would be happier. If you have calipers that demand a lot of displacement it’s also possible that the move to a 19mm master could leave you without displacement in reserve. The details matter.

Unfortunately the way most cars end up with modified brakes it’s sort of a “well this worked for so & so” or “ this worked on the Boxter” so it’ll be OK. Very few people have done either the basic engineering or the trial and error testing & tuning to know if they have an optimal system for their intended purposes. It’s not easy to do that testing on public roads, and it’s easy to lose sight of edge cases that matter (hot brakes, balance on wet pavement when cornering, brake balance vs load in front or rear trunk, etc.)

Long way to say that the system as built may not be right for you.

There a multiple ways to achieve the goal as you noted.

Good point about the 21mm pedal being higher for the same amount of braking force. The master is ATE. The rest of the package is S calipers up front, 914-6 gt calipers rear with stock proportioning valve all remanufactured by PMB- so in this case all the trial and error testing was done by Porsche.... Only difference is that the car is not flared and therefore not have wider track and staggered tires.

I'd say the balance is good. I was came into a wet corner going over a bridge the other day- the kind that can mean 'spin' if you do anything too suddenly. A gentle squeeze on the brakes and the car slid a little with slight understeer but close to neutral. Gently off the brakes after shedding some speed and suspension set right back in the groove. Little throttle on the way out and just a kiss of over steer as I scooted back into the dry. (this spot is always wet so it was no surprise.) This is on 185/70 15" XWX tires and gas burners. All together the combo is a great balance for learning the traits of the 914.

Anyway after a short drive today toe and heel is way easier. Transitions way smoother. If I were at the track I'd take it back (closer to) the original position.



Pete

[emerygt350]

Shoes matter too. I used convers all stars on the track and it was great. On the street I often go for some Saucony hybrid trail shoes. Wider tread that grabs that break pedal better on the ball.

[peteinjp]

No doubt about that. I always drive this car with the same shoes actually. Not a well known brand but fit my feet perfectly ( a first BTW) and are thin enough to be tactile. Wider than a track shoe.

Joe Nimble trekking shoes- also German with Michelin rubber.

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.joe-nimble.com-25723-1686839869.1.png)

(IMG:http://www.914world.com/bbs2/uploads_offsite/www.joe-nimble.com-25723-1686839871.2.jpg)

[bkrantz]

Meanwhile, those of us with, um, bigger feet (12EE for me) wish the brake pedal could move a little to the left. I have the center console, with the clever indent next to the accelerator, but I still can get my foot stuck trying to go from gas to brake if I am wearing normal shoes. Here's my solution, some Merrell barefoot style shoes:

[peteinjp]

Big feet here too and it’s a major problem since I live in Japan. I can only try on shoes in Tokyo!

Post to drive report: heel/toe is MUCH better with his arrangement. Amazing what a small adjustment can do. Now the pedal is just a tad too low for really hard braking. The final answer is to print a slightly thicker stop for the pedal and take the hose off.

Test grounds- this is just a short stretch. The whole course is a 2.5 hour spin (Google says 4 hours…)

[BillJ]

21mm master cylinder is not a good choice for what you list. 19mm would be max and actually is what i have with the same calipers.

[peteinjp]

21mm master cylinder is not a good choice for what you list. 19mm would be max and actually is what i have with the same calipers.

That’s good to know. What’s the reasoning for the 19mm? The 21 seems pretty good in terms of modulation but does take a good shove reach the limit.

Pete

[BillJ]

I am quoting someone else here but this was a good description:
A larger diameter master will require a shorter stroke to move the same amount fluid, thus giving a shorter pedal that requires more force and results in less feel. If you go too big with the master cylinder, the extreme case is it becomes an on/off switch and may require serious leg strength to create real friction.

So your pedal travel issue is a direct result of putting too large an MC in the system.