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Discussion Starter #21
Just got back from vacation, and gotta kick myself for this topic that I also posted on 5 yrs ago (?). Wow, just lived with the issue until it annoyed me long enough that I thought it was a new issue. Dumb stuff. Memory farts.
This year I work on it, better or works, cut, weld, adjust, whatever. Some good info in the dialogue here, hope it helps someone else down the road too!

Don L.
 

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Discussion Starter #23
Ok, ready to put this thread to rest! I came up with some adjustments, sort of a compromise. Not everyone would like this setting, but I am ok with it. I adjusted the rod that goes from the clutch pedal into the clutch MC almost as far as it would go. This moved the engagement point of the pedal much lower to the floor. Now there was a huge looseness of the clutch pedal at the top of the travel, so much that the pedal had trouble retracting all the way upward after pressing the pedal. So, there is a electrical switch and upper pedal stop that seemed to be adjustable, limiting how high the pedal can go. I disconnected the wiring connector, so it wasn't functioning anymore as a necessity for starting the car (I'm guessing). I adjusted this pedal stop/switch so the top of the pedal travel (location of pedal at rest) is much lower. Now, this looked kinda funky to me, wasn't sure I would like it as the clutch pedal was previously at about the same height as the brake pedal, as in most cars I looked at. Now the clutch pedal is a good 1-2 inches lower in upper height than brake pedal.

So clutch travel is much less, engagement point is closer to the floor, the rod into the MC is loose enough at rest that I believe the clutch is fully engaged when needed. Yes, looks odd but drives well. I will live with this for now. I realized I was not going to get exactly what I wanted.

Don L.
 

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Discussion Starter #25
Oh, good to know! Cruise control has been gone about 20 yrs now :)

Switch does a nice job as a stop for the upper pedal travel.

Don L.
 

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I too like my clutch to start engaging right off the floor like you do. Sometimes I simply rotate my left foot while leaving the outside of it on the "dead pedal" to take off from a stop. Although I have a W58 with all stock hydraulics and a Centerforce Stage 1 clutch, which is obviously different from what you have, besides being able to easily engage any gear from a stop and being sure that your clutch is fully engaged with the pedal released because you have sufficient free play, it's also important to verify that your clutch fully disengages at high RPM. Otherwise, your synchros will suffer. I can't remember exactly how to properly check for this at the moment. But I do remember that I saw the procedure on a transmission rebuilders site many years ago.
IIRC, it involves revving to near red line and verifying that you can still easily engage any gear and that once engaged, that there's absolutely no movement of the car. This ensures sufficient travel for complete disengagement at any RPM. It was many years ago that I actually checked this myself, so I'm not 100% certain of the exact process now. But a little searching transmission rebuilders sites should find that info.
I don't think I'd have a problem with the pedals at different heights. It's often this way on race cars. But that's probably more because racers rarely if ever use the clutch to change gears and this could possibly make hitting the wrong pedal, even partially, even more unlikely. But I'm guessing here. I rarely use my clutch to shift either having learned to "speed" shift at a very young age. Having the pedals at different heights might also be helpful in heel and toe usage as well.
Assuming that everything is within normal wear ranges and that everything works as it should, which I definitely know isn't a good thing to assume, especially on a track car, it might help if your brake pedal was a little lower provided there's still plenty of safety margin above the floor. I think of this for two reasons. I had one company car many years ago (I think it was an 05 or 06 Grand Prix) that when I tried to hit the brakes quickly, my knee would sometimes hit the lower dash before my foot was high enough to hit the brake pedal. This always delayed braking somewhat at best and sometimes made my leg sort of numb which also adversely affected threshold brake feel. Neither of these is ever good! The only workaround was for me to try to consciously keep my leg tilted at an angle to prevent this as much as possible. Thankfully, I didn't have that vehicle barely 2 years. But it definitely took a few very close calls to figure out the problem. Of course, something like this is quite uncommon in most street vehicles and would likely never happen on a track car.
Also, braking might be easier and more controllable if the pedal was slightly lower possibly allowing your heel to remain on the floor. I know that some folks like their pedals this way because it makes them both easier to operate this way and more controllable for them as well. So how things usually are really isn't important if different works better for you. Of course something out of the ordinary might be a problem with multiple drivers that aren't familiar with a different setup. Just my 2 Canadian pesos worth. YMMV.
 

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Whistles
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ray85p,

Do you remember how to get the clutch to engage on a the W58 close to the floor? If so, the same or similar method might work for Don too.
 

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I adjusted the rod between the pedal and master cylinder shorter until clutch engagement begins by where I prefer. This also increased pedal free play, which I adjusted by lowering the pedal height slightly with the cruise control defeat switch bracket until it was on the very loose end of spec. This is what Don did as well. I just didn't adjust either quite as much as he did.
Also, as my setup differs from his, so do the adjustments required for similar operation. For example, my Centerforce Stage 1 clutch isn't exactly the same as an OEM clutch, so proper pedal height and free play, which should be set to OEM specs, requires adjustments to both compared to simply installing a new OEM type replacement clutch. These typically wouldn't require any (significant) adjustment to either and both would still likely be in spec. This assumes that the replacement parts are manufactured to the same spec AND that flywheel surfacing be done properly with the proper step depth maintained. Most aftermarket clutches differ at least slightly from OEM and generally will require adjustments to be set up properly. I initially set everything to spec, but later adjusted it to my liking. It's been working fine for many years and lots of miles as it is. Also, I didn't have any pedal return issues like Don did likely because my adjustments were smaller. But Don also is using an R154. From what I've read, when adjusted to spec, clutch engagement typically is higher than with a W58. I believe this is what led Don to make the adjustments he did and why his adjustments were more than mine to get similar results. I hope this explains everything. If not, LMK.
 

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Discussion Starter #29
@ray85p: Thanks for the feedback! I totally agree with what you described! For now, it feels good to my low functioning left leg, as its slower and weaker than when I started autocrossing. This adjustment is purely to enable me to continue enjoying my hobby, as my senior years arrive. I will keep aware of the clutch fully disengagement when pressed, seems not a problem at the moment as engagement is not THAT close to the floor and clutch pedal does continue to travel a bit after disengage.

I left foot brake at autocross, so I was concerned the lower clutch pedal make have me hitting the left side of the brake pedal when trying to left foot brake. Thankfully that hasn't been an issue yet. The height of the brake pedal right now works for me as it lines up well with the gas pedal if I try to heel/toe downshift. Stepping on the brake pedal now gets it to about the same height as the gas pedal, so I do more of a side/side rather than classic heel/toe, but it works for me ok.

Life for me is just like issues with the Supra. All about adapting and making it to the next day, or race. The alternative really sucks.

Don L.
 

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Glad I was able to help. And you're likely correct that your clutch disengages sufficiently at high RPM. Otherwise, from what I remember, you'd have had problems by now. It still might be wise to search for the exact test for this though. From what I remember, the test will show an issue that would be virtually impossible to detect otherwise. If I can find it, I'll post the link.
Well, I found the article but the link doesn't work. It's called "clutch drag kills synchros" and it's at jackstransmissions.com.
 

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Am I backwards because I like the clutch to catch high so I only have to full-throw the pedal to start the engine and leave from a dead stop?
Never really thought about it.
 

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Provided there's sufficient pedal travel to ensure full disengagement as well as enough free play for full engagement, all is well. There's no problem with either method. Technically they both fall within acceptable limits although not necessarily within OEM specs.
 

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Discussion Starter #33
I also noticed with the clutch pedal operating range lower to the floor now, I am able to work the clutch pedal usually with my left heel on the floor, mostly. This takes much of the strain off of my left leg. I was in some stop and go traffic today in the supra. By the time I got home I was anxious to get into my Prius and have an easy drive! However, the recent changes have improved the driveability of the Supra, but its still a beast to drive on the streets.

Don L.
 

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I'll bet both of our attitudes towards street driving as it's deteriorated to everywhere these days would improve significantly if our cars were equipped with special lasers that would kill stupid drivers for 10 minutes. Real stupid ones for 20. Then they'd come back to life and know they must have done something seriously stupid. Ha! The amount of effort it currently takes to maintain my own safety as well as those around me, while well below what I'm capable of, is still way too high to make it anything above just barely tolerable when absolutely necessary.
Now my occasional late night 90 mile road racing loop.... 90 minutes that drains the frustration that surviving among and saving all the stupid people God herself can't handle generates. And usually just about 90 minutes for what would typically be just under twice that. Hypothetically speaking of course about a purely fictional character that in no way represents any real person, so I allege.
 

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:badger::badger::badger::badger::badger::badger:
 

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I was born the same year as my 82 Supra, I'm like medium young. I have been known to do barbell squats until I almost puke just for the fun of it though, so a clutch pedal aint no thang.
 

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Discussion Starter #38
I recall being fairly young when I bought my '84 Supra, in 1984 :laugh:

Squats? That's a one way trip for me now. Go down, I'm not making it back up. Like doing any exercise, the last part of the extension, like in squats or lifting is somewhat easier than the initial effort from a bent position, at least that's how I look at it. If I could operate the clutch pedal at the upper range of travel only, it would surely be quicker shifting, less pedal travel, but leg is more bent position. Weaker position.

At least I can still hit the gas pedal pretty hard!

Don L.
 

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So you remember being young in '84? Maybe I was then too when we bought our 85 in 12/84. but I don't recall. That's my story and I'm sticking to it. At least it's easy to remember that I can't remember, I think. I sometimes wish our seats had a soft landing and easy eject feature as I'm also experiencing the same problems near maximum bend. If I could only remember to put my knee pads where I can grab them and put them on after I've already made that first "no turning back now" decent, But I can still pedal it with the best and I bet you can too.
 

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I'll bet both of our attitudes towards street driving as it's deteriorated to everywhere these days would improve significantly if our cars were equipped with special lasers that would kill stupid drivers for 10 minutes. Real stupid ones for 20. Then they'd come back to life and know they must have done something seriously stupid. Ha! The amount of effort it currently takes to maintain my own safety as well as those around me, while well below what I'm capable of, is still way too high to make it anything above just barely tolerable when absolutely necessary.
Now my occasional late night 90 mile road racing loop.... 90 minutes that drains the frustration that surviving among and saving all the stupid people God herself can't handle generates. And usually just about 90 minutes for what would typically be just under twice that. Hypothetically speaking of course about a purely fictional character that in no way represents any real person, so I allege.
You sound like someone who has to deal with Seattle area traffic everyday. I just drove back from Redmond in rush hour yesterday, I understand your pain lol
 
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