shifting w/o using the clutch...

anyone ever try this?...well today on the way home from work i tryed it out (i was going to stop if it went bad..lol). i was shocked to find that driving normal (not using the chutch) it didnt grind at all, :grinyes: if you rev match its all good. im thinking it cant be too good, but i really dont care..lol i have 3 dx trannys 2 were free and 1 is blown(due to my sister trying to drive my car...) and 1 si tranny i dont know if i want to put in... so im not too worried about blowing it...
i just wanted to know if anyone has done this before (im sure ppl have) and if it can be done racing(maybe make shifts 1/10 sec faster?)

It only works if you rev match...well works correctly. I wouldn't really recommend it for racing, just stick to using the clutch instead of messing around trying to rev match it....unless you have really good control and can do it continuously.

I had to limp a car home one day using this method, but I wouldn't recommend it for everyday driving.

i do it all the time when i am lazy or driving with my knee. but if done while racing you will most likely grind the gears

i just wanted to know if anyone has done this before (im sure ppl have) and if it can be done racing(maybe make shifts 1/10 sec faster?)
wouldn't be good for racing. When shifting up gears you have to wait for the RPMs to drop down to the right area so you can pull it into gear. Waiting for the RPMs to fall is a lot slower than using the clutch. And if you just jam it into gear without waiting for the RPMs to fall, then you're risking some wear and tear on your tranny.

Driving my truck the only time I use my clutch is starting out in first.

Basically what you are doing by shifting without the clutch is working the synchos overtime after a long night of drinking. Basically all a syncro does is match the speed of your drive gears (by either speeding up or slowing down the gears depending on a upshift or downshift) to the speed of the gears on the counter shaft to get a smooth shift. The synchro does this by having a clutch like material on it and its tapered, and the gear is also tapered, so the cone of the gear fits inside the syncro to match the speeds.

heres a pic of a syncro real quick

http://www.ae92gts.com/images/tech/trans_rebuild/204.jpg

you can see the rough material on the inside.

What you see on the outside is know as the teeth, or DOG teeth. This is what grinds when a tranny doesnt go into gear.

So anyway I kinda got off track. By shifting without the clutch you are putting excessive pressure on the synchros which will cause them to wear out prematurely. So basically its bad.

I've done it a few times. Rev match to find sweetspot and slips right into gear.

As a former professional truck driver, I'm very familiar with shifting without the clutch. It's called 'floating' in trucker-speak.
I bought my 90 Civic LX with 75,000 miles. I figured I'd save some wear and tear by rev-matching, shifting without the clutch. At 175,000 miles, my transmission was toast. One of the bearings was bad. I had never raced the car.
You're not saving any wear and tear by shifting without the clutch. The only benefit is if you're lazy or tired, and just don't feel like using your left leg. If that's your condition, just get an automatic.
4DF

It would be retarded while racing, you'd have to wait too long to shift.

Ive tried this...I cant even get the damn car into gear...at all.

Done it a few times, kinda cool for cruising around. But, Not fast by any means.

It would be retarded while racing, you'd have to wait too long to shift.

I agree. Thats when WOT shifts come into play :evillol:

Never tried one of those....prolly scare the hell outta me.... But Id be near the rev limiter already...Ive missed 3rd at about 7500rpm, and that sucked ass. Still dont think I got it much past 8 though.

my tranny is about dead, i wana try this, can someone explain how to do it, or send me a link that shows how, i dont understand the rev-matching thing?

i just rev to about 3k lift foot off gas and shift. i think it is more of a practice thing then someone telling you how to

Rev matching is trying to get the speed of your input shaft (since your not clutching, the speed of your engine) to be close to the speed of the drive dogs in your transmission, if they are not similar then they will grind and wont mesh together...so basically your letting your rpms drop in neutral untill they are low enough to mesh into the next gear....This will explain a little better, but I think it only covers downshifting...same thing really, except that instead of hitting the gas to get higher rpm for the lower gear, your letting the rpm drop to hit the higher (taller) gear. Ive completely forgotten how to input a link, so here ya go...http://www.everything2.com/index.pl?node_id=1249174 Ok so apparently this forum is smarter than me and autmatically did the input, Ill admit when Im stupid....

Rev matching is trying to get the speed of your input shaft (since your not clutching, the speed of your engine) to be close to the speed of the drive dogs in your transmission, if they are not similar then they will grind and wont mesh together...so basically your letting your rpms drop in neutral untill they are low enough to mesh into the next gear....This will explain a little better, but I think it only covers downshifting...same thing really, except that instead of hitting the gas to get higher rpm for the lower gear, your letting the rpm drop to hit the higher (taller) gear. Ive completely forgotten how to input a link, so here ya go...http://www.everything2.com/index.pl?node_id=1249174 Ok so apparently this forum is smarter than me and autmatically did the input, Ill admit when Im stupid....

thanks for repeating what I said about 5 posts ago.

If youll notice though, you said absolutely nothing about HOW to rev match, I at LEAST touched on it...ATMDC was asking how to do it, not how a syncro works. Actually I repeated almost nothing of what you said.

I drive 70 miles a day for work and hardly use the clutch. I up/downshift 75% of the time without the clutch. With the right technique there's nothing wrong with it. Learning this technique from a pro race driver was very helpful. Downshifting into a corner without the clutch is so smooth I don't upset the cars balance what so ever.

yeah its ok when you rev match it perfectly. but for someone who just revs it up and waits for it to go in while pushing on the shifter its bad.