Modified clutch stop
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- Senior Standardshifter
- Posts: 123
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Modified clutch stop
Hey guys,
I want to get a second opinion on this:
http://www.e92-lighting.com/products/E9 ... 388-0.html
Source discussion thread:
http://www.e90post.com/forums/showthread.php?t=423172
Basically means you don't have to press the clutch as far in; eliminates "dead" space.
My gut instinct says modifying the clutch pedal might cause extra wear, unknown issues down the line. Was always taught clutch needs to be ALL the way in.
What do you guys think?
I want to get a second opinion on this:
http://www.e92-lighting.com/products/E9 ... 388-0.html
Source discussion thread:
http://www.e90post.com/forums/showthread.php?t=423172
Basically means you don't have to press the clutch as far in; eliminates "dead" space.
My gut instinct says modifying the clutch pedal might cause extra wear, unknown issues down the line. Was always taught clutch needs to be ALL the way in.
What do you guys think?
2011 BMW E92 335i: Le Mans Blue, M Sport, 6MT w/ CDV Mod, BMW Performance Exhaust + Style 269 19" Wheels
- FDSpirit
- Master Standardshifter
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Re: Modified clutch stop
I personally wouldn't either, for the same reasons you've listed.
2000 Honda Civic Si- Slightly faster than your grandmomma's grocery getter......slightly.
- 4onthefloor
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Re: Modified clutch stop
This reason bugs me. You sit where you sit so that you can also have full travel range of the brake pedal, as well as comfortable control of the steering wheel. And unless you are severely disproportioned it shouldn't even be an issue.Are you tired of sitting up close to the steering wheel because the clutch pedal needs to be depressed to the floor?
It's not really a big deal to push the clutch pedal in an extra inch or two. This seems like a company trying to make money off of ricers and wannabe racers.
Two pedals, two feet, too easy.
Car: 2007 Impreza 2.5i Special Edition
http://www.standardshift.com/forum/view ... 32&t=13230
Car: 2007 Impreza 2.5i Special Edition
http://www.standardshift.com/forum/view ... 32&t=13230
- FDSpirit
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Re: Modified clutch stop
I'd like to see the end result of this thing. I can't see any good coming from this.
2000 Honda Civic Si- Slightly faster than your grandmomma's grocery getter......slightly.
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- Senior Standardshifter
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- Joined: Tue Apr 05, 2011 11:59 am
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Re: Modified clutch stop
My thanks for the replies.
I'm going to stay away from this "mod". Looks like a duck, quacks like a duck, it's probably a duck ...
I'm going to stay away from this "mod". Looks like a duck, quacks like a duck, it's probably a duck ...
2011 BMW E92 335i: Le Mans Blue, M Sport, 6MT w/ CDV Mod, BMW Performance Exhaust + Style 269 19" Wheels
- 4onthefloor
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Re: Modified clutch stop
End result is that some 17 year old puts this on his fart-canned civic hatchback, revs it up to 7k, stomps on the clutch, the clutch doesn't fully disengage and he leaves little bits of transmission all over the road.FDSpirit wrote:I'd like to see the end result of this thing. I can't see any good coming from this.
Two pedals, two feet, too easy.
Car: 2007 Impreza 2.5i Special Edition
http://www.standardshift.com/forum/view ... 32&t=13230
Car: 2007 Impreza 2.5i Special Edition
http://www.standardshift.com/forum/view ... 32&t=13230
- eaglecatcher
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Re: Modified clutch stop
Yeah I wouldn't do it...
Too easy to be at a point where your pressure plate is putting just enough pressure on the clutch to allow the transmission to shift out, but still be spinning. Great way to blow shit up.
Too easy to be at a point where your pressure plate is putting just enough pressure on the clutch to allow the transmission to shift out, but still be spinning. Great way to blow shit up.
Z1 Intake
Z1 2.5" Test pipes
HKS 65mm Hi-Power Exhaust
AMS Short Shifter
SZ Subframe Spacers
HKS Vein Pressure Converter
DDM Tuning 6000k HIDs
Z1 2.5" Test pipes
HKS 65mm Hi-Power Exhaust
AMS Short Shifter
SZ Subframe Spacers
HKS Vein Pressure Converter
DDM Tuning 6000k HIDs
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Re: Modified clutch stop
I would say that it is true that the clutch pedal needs to be depressed far enough for the clutch disc to be unclamped and free-spinning. It is also a good thing for the clutch to be released for a long enough of a time interval that it starts to coast down and match the engine speed associated with the next-chosen gear (in the case of upshifting) - reducing the work required of the synchronizers. Part of the reason for having "over-travel" is to ensure that there is always a pedal position that will result in full release of the clutch and also to provide some time for the disk to coast down. You could always hesitate or pause your upshift timing to allow more time for the disk to coast down.
Depressing the clutch release pedal until it hits its downstop is a simple way to always fully release the clutch. Otherwise, depressing it just far enough to release it somewhere North of the downstop is akin to learning to hit your notes spot-on while playing a slide trombone - when you are deaf. There is no feedback as to at what point the clutch disk is fully disengaged. If you don't quite get there and the clutch disk is dragging against the flywheel and pressure plate, it's extra work for the synchronizers and maybe a little extra wear inside the tranny as you fight the torque lock coming out of gear, etc.
Getting the clutch pedal to consistently hit the downstop on each shift requires seat positioning that is most likely closer to the steering wheel than the seat positioning required to actuate the brake or accelerator pedals - the same person driving a slushbox version of that same vehicle could praps sit further away from the steering wheel. For most slushbox drivers, as long as they sit close enough to steer the car, they will be close enough to operate the brake-obama and accelerator pedals.
Depressing the clutch release pedal until it hits its downstop is a simple way to always fully release the clutch. Otherwise, depressing it just far enough to release it somewhere North of the downstop is akin to learning to hit your notes spot-on while playing a slide trombone - when you are deaf. There is no feedback as to at what point the clutch disk is fully disengaged. If you don't quite get there and the clutch disk is dragging against the flywheel and pressure plate, it's extra work for the synchronizers and maybe a little extra wear inside the tranny as you fight the torque lock coming out of gear, etc.
Getting the clutch pedal to consistently hit the downstop on each shift requires seat positioning that is most likely closer to the steering wheel than the seat positioning required to actuate the brake or accelerator pedals - the same person driving a slushbox version of that same vehicle could praps sit further away from the steering wheel. For most slushbox drivers, as long as they sit close enough to steer the car, they will be close enough to operate the brake-obama and accelerator pedals.
'08 Jeep Liberty 6-Speed MT - "Last of the Mohicans"
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Re: Modified clutch stop
Is that what stops you from popping out of gear, unless you are at the point of zero acceleration/deceleration?Rope-Pusher wrote: torque lock
What is it physically?
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Re: Modified clutch stop
Yeth.Reverence wrote:Is that what stops you from popping out of gear, unless you are at the point of zero acceleration/deceleration?Rope-Pusher wrote: torque lock
What is it physically?
It's a back-taper on the synchro sleeve that resists efforts to slide it off the gear clutching teeth unless you stop or seriously reduce the torque being transmitted. Put your accelerator pedal to the floor and try pulling the shift lever back out of 1st and into 2nd while the car is still accelerating - it can be very tough to do, but if you keep applying pressure with your hand and wait until the engine hits the rev limiter, torque is reduced, the synchro sleeve slides off of the 1st gear clutching teeth and you can slam it into 2nd without using the clutch pedal or letting off the accelerator pedal - KIDS, TRY THIS IN A RENTAL CAR BEFORE YOU DO IT IN YOUR OWN CAR. NOT THE THING TO DO IF YOU HAVE WEAK SYNCHROS.
'08 Jeep Liberty 6-Speed MT - "Last of the Mohicans"
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Re: Modified clutch stop
OK, Thankth pope, very informative!
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Re: Modified clutch stop
Yawana know the point in the duty cycle when the clutch pedal sees it's highest loading?
When the driver is digging into his back pockets to get to his wallet in the drive-thru line!
When the driver is digging into his back pockets to get to his wallet in the drive-thru line!
'08 Jeep Liberty 6-Speed MT - "Last of the Mohicans"
Re: Modified clutch stop
Who rents sticks these days?Rope-Pusher wrote:... KIDS, TRY THIS IN A RENTAL CAR BEFORE YOU DO IT IN YOUR OWN CAR...
Re: Modified clutch stop
This has been a popular mod with many different makes/models for years now. In my opinion, as long as the decreased clutch pedal travel still allows the clutch to fully disengage, there should be zero issues. The G35/G37 guys have a really long clutch pedal travel and an engagement point that is almost at the very end of the pedal travel. So many of them choose a very aggressive clutch stop. I drove my friend's G before and after the clutch pedal stop modification and it did make a noticeable difference.Charles421 wrote:Hey guys,
I want to get a second opinion on this:
http://www.e92-lighting.com/products/E9 ... 388-0.html
Source discussion thread:
http://www.e90post.com/forums/showthread.php?t=423172
Basically means you don't have to press the clutch as far in; eliminates "dead" space.
My gut instinct says modifying the clutch pedal might cause extra wear, unknown issues down the line. Was always taught clutch needs to be ALL the way in.
What do you guys think?