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I've previously posted on this issue, but I've been thinking about the issue of synchro wear and I wanted to bring this up for discussion again. Someone mentioned that double-clutching on a downshift is unnecessary due to the capability of the IS's synchro, while this is fine and I've executed downshifts while cornering at speed with no problem synching up gears--just a single press of the clutch and blip of gas--my question is: how much toll does this take on my synchro? Would double-clutching benefit the lifetime of the synchro enough to cancel out the additional wearntear on the clutch? Is it just good practice for those of us who want to pursue sportscars of the more pure sense? Not all cars that I drive in the future will have a modern synchromesh... Anyway, I know some .netters have more experience with this than I do and I'm interested to hear opinions.
 

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i would say... none.
if you're double clutching right, you're not using the synchro.
if you are doing 1/2 assed double clutching(smashing it into a gear w/o rev matching), the synchro will have to work extra hard due to that 'smashing', which will kill it eventually.

hrm... im think someon more knowledgable can explain it better.
 

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Blipping the throttle while clutching in (i.e. rev-matching) will not hurt your transmission. However, not doing it will induce wear on your synchros, throwout bearings, cluthc, etc...

IMO, double de-clutching (as it should be called) is unnecessary, esp. in synchronized gearboxes. I've tried it once at the track and it definitely is a lot of wasted effort. The proper way and the only way to downshift is heel/toe (or toe/heel) downshifting. Movements are very efficient. You know how this goes. Before you enter corner you, first step on the brake, clutch-in, go into lower gear, while clutching-in you put one side of your right feet(the ball of your foot) on the brake (while braking) and roll your heel onto the accelerator to blip throttle, release clutch, and gas out.

Toe/heel downshifting is very easy in our cars. It does take practice. A lot of practice. If you rev-match like what you are explaining, its like doing a heel/toe downshift except you are not stepping on the brakes.

Just remember that brake pads are far easier and cheaper to replace than a clutch (or tranny). You don't downshift to brake, that's what your brakes are for. Downshifting is primarily used to setup for maximum power out of a corner without upsetting balance of car. Hope this helps.
 

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speedtrap said:
...Before you enter corner you, first step on the brake, clutch-in, go into lower gear, while clutching-in you put one side of your right feet(the ball of your foot) on the brake (while braking) and roll your heel onto the accelerator to blip throttle, release clutch, and gas out...
I'd like to add a little correction.
It works better if clutch, blimp, go into lower gear, release clutch, NOT clutch, lower gear, blimp, release clutch. That makes "blimping" easier too since you can feel with the shifter when the RPMs are matched - it will slide into its position with very little force.
 

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vlad_a said:
speedtrap said:
...Before you enter corner you, first step on the brake, clutch-in, go into lower gear, while clutching-in you put one side of your right feet(the ball of your foot) on the brake (while braking) and roll your heel onto the accelerator to blip throttle, release clutch, and gas out...
I'd like to add a little correction.
It works better if clutch, blimp, go into lower gear, release clutch, NOT clutch, lower gear, blimp, release clutch. That makes "blimping" easier too since you can feel with the shifter when the RPMs are matched - it will slide into its position with very little force.
I agree, blipping then going into gear is MUCH better than clutch, shift, then blip. When you blip before the shift, it allows for a easier shift into the desired gear and it wont have that feeling that your forcing it. NEVER FORCE.
 

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to anyone that uses their brakes instead of downshifting and uses the exuse "brakes are cheaper than a clutch", please give your car to someone that really enjoys driving... you dont deserve to drive stick...

a nice 5-4-3 downshift coming into a corner is probably the most engaging experience behind the wheel...and your missing it
 

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^^^^
You forgot 2. :wink:

That 2 also has 2 options:
1) Engine braking while going into the turn to tranfer weight forward so the front tires have more grip. If too much engine braking is applied, severe oversteer may occur.
2) Giving it gas for a little oversteer. One must be careful not to understeer if going too fast.
 

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There is a ton of information on the web about rev matching and double clutching. Bottom line is that in a world of automatic transmissions even the sports type driver ( read: manual guys) are too lazy to double clutch or rev match.

Who knows next you will be power shifting? :lol: :lol: :lol:
 

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^^^^
Failure to perform Rev-Matching comes from inexperience rather than lazyness.
 

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HoustonLex said:
to anyone that uses their brakes instead of downshifting and uses the exuse "brakes are cheaper than a clutch", please give your car to someone that really enjoys driving... you dont deserve to drive stick...

a nice 5-4-3 downshift coming into a corner is probably the most engaging experience behind the wheel...and your missing it
You don't quite to seem to understand the point of downshifting. You don't downshift to slow down, you downshift to gain maximum power out of a turn. Brakes are in cars for a reason, to slow down. Go and read some books on performance driving. It will tell you the same thing.

Why do a 5-4-3 downshift when you heel/toe and go directly into 3 from 5 (assuming safe rpms)?

vlad_a...I may actually do what you said, but when I do it, its more instinctive. I don't think what to do, I just do it. I agree, rev-matching takes time to learn and experience.

Just drive!!!
 

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Question.. I do all the stuff you guys are mentioning on my daily drive home. When I come to the 105 West after leaving the 110 North, there's 270 degree turn that I usually drop from 5th gear to 3rd gear. I usually do some type of syncronizing when I jump into 3rd. I usually hit clutch, blip the trottle while putting it into 4th or even 3rd, as I am letting back up on the clutch, I press the brake to slow down a little for the turn.

But my question is, totally unrelated. In normal everyday traffic, can you press the clutch too much? as in, is it a good idea to stay in the gear you are in when you come up to slow traffic and try to motor your way back up to speed later on, or is it better to shift down. Example, you are doing 50mph in 4th, but you come up to a car doing 25, normally I would shift down to 3rd or so, until that car goes faster again, then Id shift back to 4th. Or should you stay in 4th, save that little bit of clutch action and the throwout bearing wear and tear. I really didn't know or care what the throw out bearing was for until I got this car and after a year had to get a new one. My first car was a mazda GLC, I drove it for 10 years, replaced the clutch once. But I do remember a friend telling me way back then that I drive a clutch bad, I think he meant I shifted way too much. Back then I didn't know that could be a problem. Anyway, now a days I find myself concentrating way too much on trying to save the clutch. You shouldnt have to worry about stuff like that. Lunch time, Im going to have some fun on the L-Teezy.
 

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^^^^
If driving in traffic, I try not to downshift while I can stay in gear down to 1,200 RPMs. Below that I downshift.

While I was out of the country, I have observed people driving 10 MPH in 4th gear while turning. The engine was stalling, but the vehicle velocity was keeping it barely running. I'm assuming the reason for such driving is to prolong the life of the clutch.
 

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While we are on the subject....
Whats the proper heeltoe? (notice I got big feet so I can't do it anyway)


Picture 1 or 2
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Picture 1

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Picture 2
 

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either and neither....

there is no rule, I know people that do it both ways...


I actually split my foot, and use the very left tip of the shoe to grab the brake, and then dip into the throttle with the right edge of my shoe... heel is basically on the floormat the whole time...
 

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I've done both heel/toe and left foot breaking, I personally find it easier to left foot break, but either one gets the job done. It really comes down to personal preference and what works best for you on your particular car.


btw, heel/toe is just the name, you dont really use your heel :) you just use either side of your toes.
 

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speedtrap said:
HoustonLex said:
to anyone that uses their brakes instead of downshifting and uses the exuse "brakes are cheaper than a clutch", please give your car to someone that really enjoys driving... you dont deserve to drive stick...

a nice 5-4-3 downshift coming into a corner is probably the most engaging experience behind the wheel...and your missing it
You don't quite to seem to understand the point of downshifting. You don't downshift to slow down, you downshift to gain maximum power out of a turn. Brakes are in cars for a reason, to slow down. Go and read some books on performance driving. It will tell you the same thing.

Why do a 5-4-3 downshift when you heel/toe and go directly into 3 from 5 (assuming safe rpms)?

vlad_a...I may actually do what you said, but when I do it, its more instinctive. I don't think what to do, I just do it. I agree, rev-matching takes time to learn and experience.

Just drive!!!
Thanks for the insight Mr. 74 posts....

I generally dont drive at 10/10th on the street. And I would strongly advise for you to do the same.

When driving a spirited 7/10ths back country road, I enjoy engine-braking to come into a corner. Sure I could wait 100 feet longer, slam on the brakes and come out of the apex screaming at redline, but thats not what people should be doing on the streets.

There is something called the point of no return in racing. If you are actually getting close to that point on streets, your an idiot.
 

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thedon said:
While we are on the subject....
Whats the proper heeltoe? (notice I got big feet so I can't do it anyway)


Picture 1 or 2
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Picture 1

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Picture 2
you know... the word(s) 'heel and toe' got originated wayyy back when gas was the middle pedal. back in the day, they toe'd the brake, and gas'ed w/ heel. many things changed since then (such as gas pedal moving to the right), but the word(s) stayed the same.(it shoulda changed to 'toe and heel' but.. ya...)

picture 2 is the proper way to do 'heel n toe'. In racing, you have to go full brake to full gas(in theory). if you do like what pic#1's doing, you cant modulate brake pedal well.

now, if you're the master of double clutching, you wont even have to use clutch at all. just lift the gas a lil, put the gear in neutral and blip, and slide it into a lower gear.(i heard this is bad for gears w/ synchro.. but im hearing mixed answers).
 
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