3rd gen Engine/Drivetrain Engine/Drivetrain Modification Discussions for 1999-2003 Models Only (BJ chassis)

B&M Shifter Problems...

Thread Tools
 
Search this Thread
 
Old December-5th-2002 | 03:56 PM
  #16  
Scarmiglio's Avatar
Protege Enthusiast
 
Joined: Dec 2002
Posts: 240
From: Orange County, CA
Scarmiglio is on a distinguished road
When shifting from 1st to 2nd, try double clutching to go easier on your synchros. This takes a bit of practice, but try this

1. Take it close to redline in first gear (6000-6500rpm)
2. Engage the clutch and take it out of first gear
3. Once the clutch is engage, hit the gas to keep your engine revs up (preferebly 5000-5500rpms)
4. Pull it into second gear and "smoothly" release the clutch (do NOT drop it) while letting off the gas most of the way.

This allows you to better match engine speed to clutch speed and, if done properly, there will be a smooth transition and you will come into 2nd gear at 4500rpms or so which is right in the powerband. This can be done as quickly as a normal shift with practice, but it definitely takes practice. This is not something I would recommend for daily driving, but it will help when racing.
Old December-5th-2002 | 04:03 PM
  #17  
dynamho's Avatar
Registered User
 
Joined: Jun 2002
Posts: 265
From: New York City
dynamho is on a distinguished road
Are you sure about this because I'm having trouble buying this.
This will work when downshifting but I highly doubt it's going to help when upshifting.

BTW, this method works beautifully when downshifting, particularly from second to first.

The only way your method is working for upshifting is because you're spending all your time double clutching thereby giving the transmission gears and layshaft enough time to slow down to match a speed appropriate to engage 2nd gear.

Originally posted by Scarmiglio
When shifting from 1st to 2nd, try double clutching to go easier on your synchros. This takes a bit of practice, but try this

1. Take it close to redline in first gear (6000-6500rpm)
2. Engage the clutch and take it out of first gear
3. Once the clutch is engage, hit the gas to keep your engine revs up (preferebly 5000-5500rpms)
4. Pull it into second gear and "smoothly" release the clutch (do NOT drop it) while letting off the gas most of the way.
Old December-5th-2002 | 04:22 PM
  #18  
user 11897647645's Avatar
Thread Starter
Banned
 
Joined: Jul 2002
Posts: 1,111
user 11897647645 is on a distinguished road
I've done that before on the upshifts, but at low RPMs for a very smooth shift. On a day when the snow is gone I can try at really high RPMs and give your idea shot.
Old December-5th-2002 | 06:20 PM
  #19  
dynamho's Avatar
Registered User
 
Joined: Jun 2002
Posts: 265
From: New York City
dynamho is on a distinguished road
In mechanical theory double clutching can't smooth out upshifts from 1st to 2nd at high RPM.

If it's working then, like I said, it's due to the fact that you're letting your tranny slow down while doing that extra clutching.

With low RPMs, you don't even need to do double clutching. Just press the clutch down and wait a split second for your tranny to slow down. Then engage 2nd. If you shift at 2000RPM, you don't even need to wait, the synchro itself can take care of it.

Perhaps I should be more authoritative then.
Double clutching only smoothens out downshifts!
Old December-9th-2002 | 02:32 AM
  #20  
Arghman's Avatar
Protege Enthusiast
 
Joined: Sep 2002
Posts: 282
Arghman is on a distinguished road
Dude, I was noticing the same thing. I left my SS in for like 3 weeks or so and it was still kinda crappy. It also got all slinky and crap after like an hour of driving. The shifter wouldnt spring back to the vertical position in neutral, it would just stay all slopped down to the side.
I put my stock shifter back on last week and i like the feel better now. Although its longer, the amount of effort required feels better, and i dont feel like im raping my tranny either, like GCS was saying.
I can shift faster now too.
Old December-9th-2002 | 09:03 PM
  #21  
Scarmiglio's Avatar
Protege Enthusiast
 
Joined: Dec 2002
Posts: 240
From: Orange County, CA
Scarmiglio is on a distinguished road
Originally posted by dynamho
In mechanical theory double clutching can't smooth out upshifts from 1st to 2nd at high RPM.

If it's working then, like I said, it's due to the fact that you're letting your tranny slow down while doing that extra clutching.

With low RPMs, you don't even need to do double clutching. Just press the clutch down and wait a split second for your tranny to slow down. Then engage 2nd. If you shift at 2000RPM, you don't even need to wait, the synchro itself can take care of it.

Perhaps I should be more authoritative then.
Double clutching only smoothens out downshifts!
Whoa there! I didn't even get a chance to answer your first post! I wasn't talking so much about smoothing out the shifting as having better launches and an easier 1st to 2nd shift. I've found that it takes a second to engage second gear when you leave first gear at high RPMs (Redline). I "double clutch" or rather give it gas coming into second so that I'm still at or over 4000 RPM (the torque peak). I think that the 1st- 2nd gear engagement takes a second due to the speed that the transmission is spinning vs. the engine speed, so giving it gas while shifting keeps the engine speed higher. Like I said, i wouldn't recommend it on a regular basis.
Old December-9th-2002 | 10:00 PM
  #22  
user 11897647645's Avatar
Thread Starter
Banned
 
Joined: Jul 2002
Posts: 1,111
user 11897647645 is on a distinguished road
Even if you did do it on a regular basis...why would it really harm/damage anything? It's basically revving the engine in neutral. The only problem I might see would be burning the clutch at the high RPMs, but still, regularly doesn't mean it's at redline. Doing your "double clutch" method anywhere from 2-4000 RPM should be fine right?
Old December-9th-2002 | 11:27 PM
  #23  
dynamho's Avatar
Registered User
 
Joined: Jun 2002
Posts: 265
From: New York City
dynamho is on a distinguished road
My mistake for jumping the gun.

Originally posted by Scarmiglio


Whoa there! I didn't even get a chance to answer your first post! I wasn't talking so much about smoothing out the shifting as having better launches and an easier 1st to 2nd shift. I've found that it takes a second to engage second gear when you leave first gear at high RPMs (Redline). I "double clutch" or rather give it gas coming into second so that I'm still at or over 4000 RPM (the torque peak). I think that the 1st- 2nd gear engagement takes a second due to the speed that the transmission is spinning vs. the engine speed, so giving it gas while shifting keeps the engine speed higher. Like I said, i wouldn't recommend it on a regular basis.
Old December-12th-2002 | 09:03 PM
  #24  
Scarmiglio's Avatar
Protege Enthusiast
 
Joined: Dec 2002
Posts: 240
From: Orange County, CA
Scarmiglio is on a distinguished road
Originally posted by gcs118
Even if you did do it on a regular basis...why would it really harm/damage anything? It's basically revving the engine in neutral. The only problem I might see would be burning the clutch at the high RPMs, but still, regularly doesn't mean it's at redline. Doing your "double clutch" method anywhere from 2-4000 RPM should be fine right?
Revving the engine in nuetral is no big deal, it's more the punishment on your clutch/synchros/transmission and the higher probability that you'll grind gears.

I don't really see any point at 2-4000 rpms as it won't do any good.

The problem with the protege Transmission is that if you shift from first to second at redline, you will (normally) enter second below 4000 rpms (peak torque). If you are racing someone, it is preferable to keep the engine between 4000rpms (peak torque) and 6000rpms (peak horsepower). I rev the engine while shifting 1st to 2nd in an attemp to enter 2nd gear at or above 4000rpms.

A good indicator of optimum shift points is this:

(Gear ratio 1/Gear ratio 2) x torque peak = optimum shifting rpm

Where Gear ratio 1 is the gear you are shifting from and gear ratio 2 is the gear you are shifting to.

So to do some simple math: (3.307/1.842) x 4000 = 7180rpm

Our engine redlines at 6500 rpms so it is difficult to enter 2nd gear above 4000 rpms.

1st to 2nd = 7180 rpm
2nd to 3rd = 5624 rpm
3rd to 4th = 5400 rpm
4th to 5th = 5140 rpm

These shifting points will generally drop you down to 4000 rpms in the next gear, but it is still best to ride it up to 6000 rpms or even redline when racing.
Old December-16th-2002 | 03:27 PM
  #25  
Scarmiglio's Avatar
Protege Enthusiast
 
Joined: Dec 2002
Posts: 240
From: Orange County, CA
Scarmiglio is on a distinguished road
Originally posted by TheMAN
umm.... I shift from 1st to 2nd at redline all the time... and it lands me back to around 4700rpm on 2nd, how the hell can it go BELOW 4000rpm? The gears are NOT tall
But there is a disproportional gap between first and second. I'm talking about the rpms on a stock engine/tranny '02 MP5. If you've done modifications to your car then this may not be the case.

I'm serious when I say that if I don't rev the gas while shifting I drop below 4000rpms on the first to second shift (at redline). It used to freak me out until I checked out the gear ratios and realized that they are not set up that well. The WRX has slightly better gear ratios.

By percentage of 1:1 drive ratio:

MP5 1st gear = 30%, 2nd gear = 54%, 3rd gear = 76%, 4th gear = 103%, 5th gear 132%.

WRX 1st gear = 29%, 2nd gear = 51%, 3rd gear = 73%, 4th gear = 103%, 5th gear 136%.

This means that the WRX has the 1st and second gear placed 8.3% closer together than the MP5. This would a more smooth 1st to 2nd gear transition. The WRX also has a higher 5th gear for better mileage at highway speeds. This, too, would be nice.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Mike518
Mazda3/Mazdaspeed3
10
March-13th-2007 11:54 AM
semtex
1st Gen Protege/323/GLC
1
June-27th-2003 12:46 PM
TDK
3rd gen Engine/Drivetrain
7
April-15th-2003 10:10 AM
TDK
3rd gen Engine/Drivetrain
4
March-23rd-2003 11:45 AM
P5 DO OR DIE
3rd Gen Protege/MazdaSpeed/P5/MP3
5
July-31st-2002 12:18 PM

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 



All times are GMT -5. The time now is 10:29 PM.