Thanks everyone for all your great feedback!!!

Yogi

 

Sorry to hijack here but this is somewhat related. When pressing the clutch all the way in and reving at the same time, thats "burning" the clutch correct. So isnt single clutch downshifts burning your clutch (when you clutch, rev, shift, and release clutch). Im asking cause someone said that downshifting to a gear that makes the rpms too high is burning.

 

Not to hijack the OP's thread, but I have a question relating to redlining first gear:

Should it be done? Ever? I've heard from many of you that redlining in general is practically encouraged, but I've heard from friends that redlining any car in first gear is bad for the transmission. I probably won't redline first gear even if this isn't true; 1st gear is extremely short and it's usually easier for me to just shift at 6k-7k in first, and then redline 2nd. Just wanna know what the deal with redlining our car's 1st gear is.

There's a technique called "double clutching" that is typically used to make smoother downshifts while also maintaining a high RPM without putting strain on the engine or the transmission. Basically, you quickly press down on the clutch, throw it in neutral, release the clutch and give it a couple of revs, press the clutch again, and shift into the lower gear.

I know it sounds like a lot, but the entire process is done in about 2 seconds. Professionals can do it twice as fast. There's youtube videos to help you learn; try looking it up. I typically do this two or three times a day, and slowly, it is starting to come a bit more naturally. Give it a try.

 

when you not rev matching using the clutch to bringing up the rpm youre burning the clutch. if you rev match youre fine.

 

double clutch ONLY puts less stress on the syncros or is beneficial when driving cars with no syncors.
smooth down change with no braking is called rev matching, when you brake and rev match is called heel and toe.

 

Wait sorry, so basically single clutch downshifting is burning your clutch ? Theres a guy on youtube soggyrice is his username. He says to rev while while is in and while you shift, you rev match. So is this burnin the clutch or no.

 

Downshifting with a "single clutch" is only burning if you dont manually match rpms. Double clutching is good because it resets the gears, but again, is only beneficial if you actually rev match in between. Remember, double clutching will need more of a rev match since the time in between is greater than "single clutching" and will cause your rpms to drop lower.

This also goes for the guys who are redlining 1st or 2nd. I highly recommend that if you plan on doing teh "redline a day" with 1st or 2nd, you do NOT go directly to the next gear, but instead skip. For exmaple, redline 1st and then go to 3rd, or redline 2nd and then go to 4th. Unless you can jack your rpms up to about 5k between the shift, this will save your synchros big time.

Anytime you upshift or downshift and you feel the car "pull back" thats your synchro/clutch doing work, which is something you dont want if you want your tranny/clutch to last you a long time.

 

single or double clutch isnt really important when down shift when you talking about clutch wear. burning clutch is when two surfaces of the clutch is spinning at different rpm like start to move the car or down shift without rev match. when you dont rev match the moment you push in the clutch the engine rpm drops but the lower gears require much higher engine rpm. at that moment if you release the clutch, the clutch is gonna do all the work to spin up the engine. but if you use gas pedal to spin up the engine, the clutch doesnt need to do the job.


actually no. short shift puts more stress on the syncros. imaging youre going 1st gear red line then you press the clutch, the input shaft and gears are still spining at 1st gear red line speed but then youre shifting into higher gear say 3rd. 3rd has a lower input shaft speed at the same speed that 1st gear at red line. so the syncros have to "slow down" the input shaft and gears that are spining at higher rpm in order to engage the slower spinning out put shaft.
same goes to down shift. the syncros "speed up" the slower input shaft in order to engage lower gear.

double clutch can be used both upshift and downshift to speed up or slow down the input shaft for saving the syncros. tho due to theres fluid inside the transmission, the input shaft slows down due to friction so double clutch during up shift isnt that important.

 

Interesting. Thanks for the correction

 

you can try 2nd gear red line speed then push in 5th will be very hard cuz the lock ring is preventing the gear going in until the syncros has match the speed.

 

**** I dont downshift into 2nd unless im at 50mph or below... anything higher than that can hurt the tranny... My 2nd gear grinds occasionally, im getting 1st and 2nd replaced... not sure why the dealer is replacing 1st but im not going to complain.

And redlining 1st gear should NOT hurt the transmisson at all, if it does then the tranny deserves to be broken. The one thing I hate is when people baby their transmisson too much. Whats the point of a manual if you cant burnout or do some donuts? Call me crazy or stupid but I refuse to have a MT that I cant do all those things in...

Also theres real no reason to double-clutch in our cars... thats what synchros are for... I was double-clutching and I believe it started my 2nd gear down the road towards grinding... Just let the synchros do the work, or rev-match

 

Thanks again!!!

No worries about hijacking the thread, I need to learn a lot so I welcome your thoughts and questions...

Yogi

 

Is it worthless to redline in neutral? Does it have to be under load?

 

yes...

 

in neutral you like what 0.5 of a second then you backing off gas? the throttle body only opens that short amount of time doesnt do much
you need is throttle body WIDE OPEN across the whole RPM range even into the red line.

 

So... since the 6 port Renesis revs much higher in a manual car, and it's the same engine in the M/T and A/T, can I rev it past my auto's 7500 rpm safely?

 

lol when its not safe, its when rev-limiter kicking in, but with manual, you can force the engine to spin faster by over revving it. Ive seen some Civic drivers miss shifted 4th into 2nd and engine went 12000rpm and blew the engine and the transmission.
autos cant down shift if the computer thinks its gonna over rev the engine I believe.

 

So that's a yes. Ima go rev the mess out of it and watch my tank empty.

 

That would be the price of admission to some of the fun of this car..... kinda sucks it would be amazing to have this type of driving and still be able to pull 300+ miles per tank.

 

Great response! I for one have no problems red lining my 8.

 

I like third gear on-ramp pulls... As long as you get to 8k RPM you've exercised all the ports... then slow down to merge!

 

Sorry to keep dragging this on. I actually rarely rev match when downshifting . I usually clutch in, shift. Then ease off the clutch and the rpms go up. I know you said this is wearing your synchros but I've asked some people if this is okay and they say its fine and that they do it too. So how exaclty should you rev match when you down shift ? Can you just rev while you downshift (while the clutch is in)? Sorry again people say different things and I wanna know what's right

 

This thread should have been over since the first reply lol.

 

rev match:
1. clutch in
2. select a lower gear and blip the throttle to bring up the rpm
3. clutch out

if done correctly, you should feel no jerkiness what so ever.

double clutching:
1. clutch in
2. select neutral
3. clutch out
4. blip the throttle to bring up the rpm
5. clutch in
6. select lower gear
7. clutch out

now if you do double clutch down shift, you can rev a bit higher than just plain rev match so that the engine rpm doesnt drop too low when you shifting into lower gear.

now heel and toe is for changing gear when you braking such as getting ready for a turn.
same procedure as above whether you just rev match or double clutch
the difference is the right foot where the toe is on the brake pedal and the heel is on the gas pedal to blip the throttle when doing either rev match or double clutch.
1. brake
2. still braking and clutch in
3. still braking, select a lower gear while using your right foot's heel to blip the throttle pedal to bring the rpm up
4. still braking, clutch out
5. repeat 2-4 for more down shifting

by doing this, especially with a RWD car is that when you brake the weight of the car shifts forward, the rear tires are much easier to lock up. by doing heel and toe, you match the rpm to the engine smooth out the down shifts to prevent locking the rear tires up.


heres some vids.
http://www.youtube.com/watch?v=cPj9XXW25GA
http://www.youtube.com/watch?v=H3ULS7pnxyg

 

Yogi the learning dude