In the never ending quest to improve our cars, you may have noticed that our clutch pedal is unusually long for a sports car. You may have also noticed that it sits about 1.5 inches above the brake pedal. While it's an easy fix to raise the gas pedal to where it's supposed to be, see link; there are a lot of aftermarket parts such of aluminum clutch quadrants, firewall adjusters, etc. to make the clutch pedal more ergonomic and efficient. I'd like to shed some light on this subject.
Your stock clutch quadrant is plastic, and is adjustable via an adjuster pawl. Contrary to what you may think, it's actually a decent design. It's adjustable as well as sturdy. The plastic doesn't really flex, and there's not much reason to replace it with an aluminum quadrant based solely on material strength unless it's cracked or warped. An aftermarket quadrant can change the engagement point of your clutch as well as how much pedal travel is required to fully engage and disengage the clutch. It accomplishes this task via basic moment arm physics. Imagine turning a bolt with a normal wrench vs a breaker bar. You may have to press on the pedal harder, but the amount of travel of the clutch cable is increased. Note that when you remove the quadrant spring, your clutch pedal can actually feel lighter due to less resistance on rotating the quadrant. This depends on the design of the aftermarket quadrant you go with.
Stock quadrant:
Steeda Quick Release:
UPR Triple Hook:
The quality of aftermarket quadrants is all about the same, so it doesn't really matter which aftermarket quadrant you go with as long as you have a firewall adjuster.
Firewall adjusters: these things are attached inline with your clutch cable, and are installed against the engine side of the firewall. They are used to adjust the slack on the clutch cable and therefore the engagement point of the clutch. Some people use them to change the clutch pedal height as well, since you can put more slack into the clutch pedal, but I think this makes the clutch pedal feel sloppy and more like an used car from the 1980s. If used correctly in conjunction with an aftermarket quadrant, your clutch will grab at the very top of the pedal travel, leaving you with quite a bit of dead space in your clutch pedal. I quite like Steeda's design as the adjuster clicks as you turn it, giving you a better idea of how much adjustment you're making. I believe UPR copied Steeda's design so they are pretty much the same thing.
Aftermarket adjustable cables: These work very similarly to the firewall adjuster, it basically allows you to lengthen and shorten the clutch pedal to give you more range of adjustment. Lots of people have success with adjustable cables, though an alarming number of people say that they have failed and broken while driving. My advice is to stick with the OEM cable unless you need the extra range of adjustment or if a new OEM cable is too expensive. Usually you can just purchase an aftermarket clutch quadrant and clutch adjuster and the range of adjustment will be more than enough.
Clutch pedal height adjusters: There are 2 different designs out there, and I'll explain why you shouldn't go with UPR or Steeda's design. Maximum Motorsports' clutch pedal height adjuster essentially is a thick flat piece of metal that goes on your clutch pedal actuation shaft to the right of the clutch pedal arm:
It effectively changes the angle of your clutch pedal arm, and also decrease the amount of pedal travel you have. By taking out the extra travel space towards the end of the clutch pedal travel, it eliminates the dead travel space where the clutch plate is essentially just moving further away from the flywheel. Your clutch pedal will become level with your brake pedal, and if used in conjunction with an aftermarket quadrant and firewall adjuster, the clutch engagement point will shift towards the bottom-middle of pedal travel. This part is quite overpriced though, you're essentially paying $20+$10 shipping for a piece of metal and a bolt. Jegs has a copy of MM's design and sells it for $25 shipped, which is where I purchased mine. They also gave me a free hat and some stickers, though probably because they felt sorry for someone who paid $25 for a little piece of scrap metal. If you're handy with metal fabrication though, you can easily make your own copy for a few dollars.
Now here's Steeda and UPR's design. At this point you're probably getting the drift that UPR just copies other company's product designs and sells them cheaper. Well guess what? You're absolutely right, as UPR's adjuster can be had for $14 on ebay.
This part is essentially a stop that stops the clutch pedal from going further up. The pedal height is adjustable via the bolt on the left. I normally don't disparage products but this is a really crappy design. Not only are you forced to move the clutch engagement point down so that the clutch isn't always half-way engaged, but it also stops the clutch quadrant from resting on the cruise control clutch sensor. This means that if you install this part, you lose your cruise control function as well as any function of a 2-step launch control you install since the car will think the clutch pedal is always depressed.
LDC Free Play Correction Kit: When you install an aftermarket performance clutch, there is a lot of free play, or slack, left in the clutch pedal, which makes it very sloppy towards the top of pedal travel. The kit has a spring and a plastic spacer that pushes the clutch fork back to the stock location so that there is always tension on the clutch cable. It's not necessary for a stock clutch, though for aftermarket clutches it's nice since it pushes your throwout bearing back far enough so that it isn't spinning against the pressure plate 24/7. You'll need an aftermarket firewall adjuster to adjust where the clutch fork is at resting location when the clutch is released.
Again, this part is quite overpriced since it's $17+$6 shipping for a spring. I made my own for $3 from a spring and a plumbing spacer found at Ace Hardware. The spring is #173 on their shelf of springs.
Anyway, my current setup includes Jeg's clutch pedal height adjuster, Steeda's double hook quadrant, and Steeda's firewall adjuster, and it feels fantastic. It's firm, communicative, and there's absolutely zero slack in the cable. I set my clutch engagement point to 1.5 inches off the floor, and my clutch pedal is level with my brake and gas pedals. There is room at the top and bottom of pedal travel so that my setup isn't riding the clutch, and there is plenty of disengagement space so that I'm not grinding the gears. Not only are my shifts are now firmer and faster due to faster clutch engagement and less pedal travel, the clutch is more sensitive and actually feels like it belongs in a sports car. Also my cruise control and launch control work perfectly fine.
Hope you found this informative and thanks for reading!
Images borrowed from americanmuscle, UPR, Steeda, Lethal Performance, and Maximum Motorsports.
Your stock clutch quadrant is plastic, and is adjustable via an adjuster pawl. Contrary to what you may think, it's actually a decent design. It's adjustable as well as sturdy. The plastic doesn't really flex, and there's not much reason to replace it with an aluminum quadrant based solely on material strength unless it's cracked or warped. An aftermarket quadrant can change the engagement point of your clutch as well as how much pedal travel is required to fully engage and disengage the clutch. It accomplishes this task via basic moment arm physics. Imagine turning a bolt with a normal wrench vs a breaker bar. You may have to press on the pedal harder, but the amount of travel of the clutch cable is increased. Note that when you remove the quadrant spring, your clutch pedal can actually feel lighter due to less resistance on rotating the quadrant. This depends on the design of the aftermarket quadrant you go with.
Stock quadrant:
Steeda Quick Release:
UPR Triple Hook:
The quality of aftermarket quadrants is all about the same, so it doesn't really matter which aftermarket quadrant you go with as long as you have a firewall adjuster.
Firewall adjusters: these things are attached inline with your clutch cable, and are installed against the engine side of the firewall. They are used to adjust the slack on the clutch cable and therefore the engagement point of the clutch. Some people use them to change the clutch pedal height as well, since you can put more slack into the clutch pedal, but I think this makes the clutch pedal feel sloppy and more like an used car from the 1980s. If used correctly in conjunction with an aftermarket quadrant, your clutch will grab at the very top of the pedal travel, leaving you with quite a bit of dead space in your clutch pedal. I quite like Steeda's design as the adjuster clicks as you turn it, giving you a better idea of how much adjustment you're making. I believe UPR copied Steeda's design so they are pretty much the same thing.
Aftermarket adjustable cables: These work very similarly to the firewall adjuster, it basically allows you to lengthen and shorten the clutch pedal to give you more range of adjustment. Lots of people have success with adjustable cables, though an alarming number of people say that they have failed and broken while driving. My advice is to stick with the OEM cable unless you need the extra range of adjustment or if a new OEM cable is too expensive. Usually you can just purchase an aftermarket clutch quadrant and clutch adjuster and the range of adjustment will be more than enough.
Clutch pedal height adjusters: There are 2 different designs out there, and I'll explain why you shouldn't go with UPR or Steeda's design. Maximum Motorsports' clutch pedal height adjuster essentially is a thick flat piece of metal that goes on your clutch pedal actuation shaft to the right of the clutch pedal arm:
It effectively changes the angle of your clutch pedal arm, and also decrease the amount of pedal travel you have. By taking out the extra travel space towards the end of the clutch pedal travel, it eliminates the dead travel space where the clutch plate is essentially just moving further away from the flywheel. Your clutch pedal will become level with your brake pedal, and if used in conjunction with an aftermarket quadrant and firewall adjuster, the clutch engagement point will shift towards the bottom-middle of pedal travel. This part is quite overpriced though, you're essentially paying $20+$10 shipping for a piece of metal and a bolt. Jegs has a copy of MM's design and sells it for $25 shipped, which is where I purchased mine. They also gave me a free hat and some stickers, though probably because they felt sorry for someone who paid $25 for a little piece of scrap metal. If you're handy with metal fabrication though, you can easily make your own copy for a few dollars.
Now here's Steeda and UPR's design. At this point you're probably getting the drift that UPR just copies other company's product designs and sells them cheaper. Well guess what? You're absolutely right, as UPR's adjuster can be had for $14 on ebay.
This part is essentially a stop that stops the clutch pedal from going further up. The pedal height is adjustable via the bolt on the left. I normally don't disparage products but this is a really crappy design. Not only are you forced to move the clutch engagement point down so that the clutch isn't always half-way engaged, but it also stops the clutch quadrant from resting on the cruise control clutch sensor. This means that if you install this part, you lose your cruise control function as well as any function of a 2-step launch control you install since the car will think the clutch pedal is always depressed.
LDC Free Play Correction Kit: When you install an aftermarket performance clutch, there is a lot of free play, or slack, left in the clutch pedal, which makes it very sloppy towards the top of pedal travel. The kit has a spring and a plastic spacer that pushes the clutch fork back to the stock location so that there is always tension on the clutch cable. It's not necessary for a stock clutch, though for aftermarket clutches it's nice since it pushes your throwout bearing back far enough so that it isn't spinning against the pressure plate 24/7. You'll need an aftermarket firewall adjuster to adjust where the clutch fork is at resting location when the clutch is released.
Again, this part is quite overpriced since it's $17+$6 shipping for a spring. I made my own for $3 from a spring and a plumbing spacer found at Ace Hardware. The spring is #173 on their shelf of springs.
Anyway, my current setup includes Jeg's clutch pedal height adjuster, Steeda's double hook quadrant, and Steeda's firewall adjuster, and it feels fantastic. It's firm, communicative, and there's absolutely zero slack in the cable. I set my clutch engagement point to 1.5 inches off the floor, and my clutch pedal is level with my brake and gas pedals. There is room at the top and bottom of pedal travel so that my setup isn't riding the clutch, and there is plenty of disengagement space so that I'm not grinding the gears. Not only are my shifts are now firmer and faster due to faster clutch engagement and less pedal travel, the clutch is more sensitive and actually feels like it belongs in a sports car. Also my cruise control and launch control work perfectly fine.
Hope you found this informative and thanks for reading!
Images borrowed from americanmuscle, UPR, Steeda, Lethal Performance, and Maximum Motorsports.
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