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Discussion Starter #1
I have some questions about shifting.

1. When you downshift. I notice that if you want to downshift and the next gear would take you into high rpm, it is extremely difficult to put the trans into that lower gear. I have heard about rev-matching to keep the car from getting squirley at the limit, but would revving the engine allow the gear to engage more easily? And on the note should you close the throttle before shoving it into gear, or does it matter if the engine is under load as long as RPM is right?

2. What is the fastest, yet safest way to shift...do you fully disengage the clutch, or just dip into the pedal a bit and 'feel' it out and into the next higher gear?

I CAN drive a stick, but when I get my car back I want to start out driving it nicely to reduce wear from the get-go.
 

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2. What is the fastest, yet safest way to shift...do you fully disengage the clutch, or just dip into the pedal a bit and 'feel' it out and into the next higher gear?

the fastest way to shift would be to depress the clutch quickly and at the same time put the car into the next gear, while never letting go of the gas...then ofcourse dropping the clutch....

the safest quickest way would be to do the short shift mod, and let go of the gas while shifting, press the clutch in...then put it in gear as fast as possible, easing out the clutch while easing in the gas as fast as you can wirthout burning up the clutch...

but the first method i use only when racing someone i want to assure i beat, and i use it from 2-3 mostly since 1st to second breaks the tires loose, i like to keep the traction..
 

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Freedy89T said:
I have some questions about shifting.

1. When you downshift. I notice that if you want to downshift and the next gear would take you into high rpm, it is extremely difficult to put the trans into that lower gear. I have heard about rev-matching to keep the car from getting squirley at the limit, but would revving the engine allow the gear to engage more easily? And on the note should you close the throttle before shoving it into gear, or does it matter if the engine is under load as long as RPM is right?
Your synchros are probably worn. I recomend double-clutching to prolong your transmission's usable life. Say you're in 5th at 2000rpm and want to downshift into 4th at whatever rpm that is for the same speed (say 3000).

step 1. Push in clutch, move the lever to neutral, and release clutch

step 2. Rev to appropriate rpm for the next gear (~3000 rpm in this case), and push in the clutch, moving the shift lever to 4th

step 3. maintain 3000rpm while letting out the clutch.
 
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Discussion Starter #4
well

Ive driven new cars, and they were all like this. I worked at a VW, Audi, Porsche dealership...all new cars, all harder to engage like I specified(porsches were easier by far though).

-->I really just want to know about the downshifting part whether having the engine at appropriate revs makes it easier on the tranny/syncros when you place it in the lower gear, and whether you should just blip the throttle to rev match or hold throttle constant. Those are my main SPECIFIC questions. This is for reduced wear on the tranny, of course.

If I can just put more pressure on the gear lever to force engagement without rev-matching that would be ideal, but I presume that wears the snycros more...am I correct?
 
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Discussion Starter #5
You do have to "rev match it" otherwise it will be a biatch to get it into the lower gear, if you're shifting in a hurry.

But that is only usually due to some drastic downshifting, like going from 5th to 2nd or something.

If you take your time though, and leave the clutch depressed for a little while, it makes it much easier. And matching up the revs always helps. If you match it up well enough, you don't even need to use the clutch and still shift very smoothly.

You can judge how far off you are in your RPM by gaging the pressure it takes to move the shifter.
 

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Go All Electric
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I'm glad I posted this on SM recently, all I have to do is copy and paste.

Just drive like an old grandma if you want to prolong life. Shift slow and make sure that the clutch is to the floor, and don't down-shift all the time unless you really need to. Don't "launch" the car. Lauching the car hard/dumping the clucth at high rpm freom a dead stop is hard on the drivetrain. Tranny will last longer this way.

Whether you're shifting like a grandma or racing/, you still need to make sure that you match crank rpm with driveline rpm. See copy/paste below.
________________________________

ridah said:
just got smoked by a z28 tonight. from 80mph up. Dunno if it's driving skills espeically when i do the 80mph runs. I just stuff in it 5th and go.

think it has something to do with the exhaust leak somewhere between the turbo and the connection to the DP, freaks out the o2 sensor.
It sounds like possibly a combo, but definitely driving skills.

80mph roll constitues a very high 3rd start or more comfortably,yet still effective 4th gear pull. If you want to win (if you want to have optimal acceleration) you don't race in 5th gear until around 120 mph.

**Since it sounds like you could use some driving tips:
Make sure that when downshifting into a gear such as 3rd at around 80mph that before engaging the gear you bring the revs up close to redline. You need to match the speed of the crank to the rest of the drivetrain (I think I got that right). You need to try to match revs for the gear that you want to be driving in with the rpm that that gear would be at the speed you are at before engaging the shift(if that makes sense).

Point: You always want to race in the lowest gear for the longest time optimal (untile redline or power loss from back-pressure) ... as long as you are getting traction in that low of a gear 8) :wink: .

Example: Cruising at 65mph(highway) in 5th and somebody comes speeding up to you that obviously wants to race or just blow by you and you don't want them to pass you. In order to gain speed asap you would do the following. Since you are travelling 65mph, you guess that about 60-65 is tip top redline of second gear (possibly rev limiter so don't go there) and about 80-85 mph is tip-top redline for 3rd gear(so, for fastest acceleration from 65mph, 3rd gear is optimal becasue it is the lowest gear that still has room to run with/more rpms unil redline/until a need for another gear change) so somewhere at about (4k-5k?) rpm is where you would be at if you were trying to maintain and accelerate from 65mph in 3rd gear ... SO you get the revs up to about (5k?) rpm with the clutch in/down (it is better to rev too high and have the clutch catch a little lower then to rev too low and have a speedy drivetrain meet a slowing crank/clutch/flywheel and potentially cause a lot of problems) then you engage the gear and the clutch may grab a little lower and then the moment the clutch grabs you floor it and shift at will at redline/power loss rpms (sometimes it is optimal to shift before redline if you can feel power loss in higher rpms from too much back-pressure).

So sorry for thread hijack, I just had to help a fellow owner out. I'd hate to hear about people losing because they pulled in the wrong gear because they didn't know how to down-shift properly or didn't even know that they should down-shift.

Great kill. I think I have tried to race 3-5 350Zs ... still no luck. Maybe they know the wrath of the mk3 beast 8) :wink: .

HTH. Best regards.
______________________________

Hope you understand matching crank rpm to driveline rpm, before you start crashing them together when engaging the clutch. I know people who have driven manual for YEARS and npt known this. <---Very sad:eek: :rolleyes: :mad: :( .

HTH. Best regards.
 

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the safest way to shit would involve you not using the clutch at all

push the lever into neutral, and match rpms... the gears willl be lines up and it will slide into gear. you dont use your syncros at all in this method, nor the clutch
 

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76celicagt said:
the safest way to shit would involve you not using the clutch at all
Only if you are really really good at it. You will still end up grinding them from time to time. In addition, clutchless shifting is slower then a quick shift. Not to mention syncros are cheaper then gears...
 

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conundrum07 said:
Only if you are really really good at it. You will still end up grinding them from time to time. In addition, clutchless shifting is slower then a quick shift. Not to mention syncros are cheaper then gears...

I was ridiculously good at this in my dad's civic. The supra is a bit harder but is still possible.

Here's a thought:

approaching a stop sign you can pull it into gear (1st or 2nd depending on speed) at idle. This is good on the clutch, and I don't think it would hurt the tranny or anything (someone please correct me if i'm wrong because i do this all the time.) The acceleration isn't great but its ok if you aren't in a hurry. This takes a bit of practice but it isn't too hard.

Oh and don' do this in front of a cop because they consider it a "rolling stop"....grrr.
 

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Ive read that shifting 200rpm past your pk hp is the optimal shifting point, not redline. Motors start to run out of steam. As far as redline downshift dbl clutch, Ive never had to do that just a quick stab at the gas pedal down shift and shes smoothed out and "synced up".
 

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chevydude said:
Ive read that shifting 200rpm past your pk hp is the optimal shifting point, not redline. Motors start to run out of steam. As far as redline downshift dbl clutch, Ive never had to do that just a quick stab at the gas pedal down shift and shes smoothed out and "synced up".

Take a look at your dyno graphs. Figure out about how long you'll be in each gear, and then find the optimum rpm range that gives you the most power. You certainly will be shifting above peak hp -- how much higher will depend on your hp curve


But it is even more complicated that that -- you make more power at the ground in lower gears (thats why people who dyno in 3rd make more power than those who dyno in 4th). So you generally will rev higher in lower gears than you will in the higher gears. And the rpm range in the 1st 3 gears is greater than in 4th and 5th.

Additionally, sometimes you won't upshift even if the next gear would offer more power. If you're close to the finish in the 1/4, its probably faster to wind out the gear you're in instead of wasting time shifting. Or if you are on a straightaway approaching a curve -- its probably faster to bump the rev limiter once or twice instead of upshifting only to downshift before the corner...
 

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7m's run out of steam way early with the ct26. anyway i'm so used to the W58 in the celica that i can slam the gears almost as fast as if i use the clutch. ive actually won a race against a honda not using the clutch except for first
 

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Rev matching allows easier downshifting and reduces wear on the trans and clutch (if done correctly). I rev match and down shift all of the time, just out of pure habit but the easiest thing to do is to just push the clutch in and use the brakes to slow down. Dropping your clutch puts huge stresses on your entire drivetrain and doesn't usually net good results anyway. Oh, on the 1 - 2 shift, don't let the clutch out until you are done shifting into second ;)
 
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Discussion Starter #14
Double clutching is a leftover from pre syncro days and is really a waist of time with modern cars. I've raced in Formula Ford 2000 using a crash box as well as tracked sedans of many descriptons. And from what I've seen among many Supra drivers is they tend not to keep the revs up where they should be when not IN the turbo(overuse of the turbo is a major problem) If you keep the rev in the 4000 rpm zone, the turbo will not come on as often.

Shifting should take place between 3800 & 4500rpm under normal driving conditions. (my sweet spot is at 4300rpm) If your 5spd isn't shifting smoothly and your finding it notchy and difficult. I would recommend replacing the tranny fluid with a high grade aftermarket brand or hi performance factory fluid. I had a very tough 2-3 shift and it didn't like down shifts into 3-4. After replacing the tranny fluid(Ford has a great performance tranny oil that's blue) My tranny felt and shifted better than new.

Learn how to make your car move fast without the turbo by maximizing you revs and making your shifting as smooth and flawless as possible.

P.S.>>> I love finding really twisty roads for this. It can be a great teacher for learning your cars best performance levels and making you smoother and faster on the Stick & Peddles.

"I'm a STICK & PEDDLE MAN myself"!!! LOL
 

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FYI 89-92 turbo sups 100 is rev limit in third :)

heal toe shifting(rev matching) IS an old art carried over from non synchroed trannies but it has PLENTY of purpose in modern trannies too!!! For example I downshift most allways when I am slowing down for a stop sign or stoplight or damn near any other thing I have to slow down for... By heal toeing I can down through the gears smooth enough that usualy my passengers dont know I am downshifting if the radio is on and cant hear the revs. It makes for a buttery smooth transition while still being under power at all times.. same goes for the twisties it allows you to drop into a lower gear and come out under power much smoother without upsetting the balance of the car... It sounds like a complicated technique but it really isnt! When I first started trying it was a chore to try to match the revs and brake and clutch and rev all at once and I thought I would never understand it.... Then the less I "thought" about it the more natural it becomes and easy... I can truthfully heal toe down through the gears as fast as I can by not heal toeing and the results are night and day as far as ride comfort and control... also after a while the clutch becomes more of a kind thing for the gears as when your matched up the stick is falling into place as your clutching anyways so it turns into more of a short stab then a fully depressed clutching...

I usually dont downshift untill I am under 2500 rps or so for normal driving(3500to4k if racing or running the twisties hard) and for normal driving there is usually right around a 500-700 rpm diffrence between each gear... for spirited stuffage I honestly dont know as the change is bigger and I "feel it" more then i count revs


Michael Morgan
 

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LJM61 said:
Double clutching is a leftover from pre syncro days and is really a waist of time with modern cars.
It is not a waste of time if you drive a car with weak synchros (like the original poster). My mr2 will not downshift nicely into 1st, 2nd, or 3rd without double-clutching. Most people would just rebuild it, but I have no problems double-clutching. And frankly I find it quite enjoyable
 
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Discussion Starter #17
THANK YOU EVERYONE

but one of my questions still isnt answered.

When you rev match should you close the throttle after rev matching and before you engage the gear(i.e. blip the throttle, then stab in the gear), or is it still ok to maintain revs(engine load) the whole time?

Assume you are granny and can take as much time as you want.
And yes I was talking about shifting into 2nd when im already traveling 40-45...getting 3rd at those speeds is easier by far. I was always under the assumption that when your syncros went that you could hear and feel the gears grinding on large downshifts...am I wrong?

thanks for all the info!
 

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Re: THANK YOU EVERYONE

yes you want to hold the throttle open enough to maintain whatever rpm you expect to see in the next gear. If you are upshifting you may want to leave the throttle closed while the engine slows down
 

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LJM61 said:
Shifting should take place between 3800 & 4500rpm under normal driving conditions. (my sweet spot is at 4300rpm)
Wow, that alot higher than what I take it to. For easy driving (most of the time for me) I drive between 1400 - 2500 rpm. Even under spirited driving do I rarely take it over 3500. Only when racing do I really rev it up.
 
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Do you want to shift to keep your car in the meaty part of the torque curve or hp curve? It makes more sense to me to pay attention to the torque and not the hp.... What do you guys think?
 
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