How can I increase shifting speed?
02-06-2008, 02:05 PM
#21
9 Second Club
Unless there is a mechanical problem somewhere, shifting is easy. I recall the video you posted, and Im sure it looked like it was taking you 1-2 secs or more to shift ??
When racing, mine usually take 0.4secs from start to finish ( foot off throttle, to back on ) so shift prob takes a fraction less.
Thats pretty much every time unless its a bad shift, or Im not trying too hard.
If the clutch was dragging a little, it would be more noticable on the downshifts, than the upshifts.
This is the Fuchs oil I had been using. Its German.
Nothing fancy, but it worked great for me.
1.9sec is hardly slamming....
I managed 1.8x on 245 Nittos, and 1.7x MT DR's. I dont think Ive ever missed a 1-2 shift. Its not that hard really, unless you have a very dodgy seat or driving position.
I hope that if I can get to a decent track, and my rear ARB works....I can get 60fts down to the 1.5x range. The tracks I race at dont always prep the surface though, which is crap.
And powershifting a syncro box is asking for something to break.
When racing, mine usually take 0.4secs from start to finish ( foot off throttle, to back on ) so shift prob takes a fraction less.
Thats pretty much every time unless its a bad shift, or Im not trying too hard.
If the clutch was dragging a little, it would be more noticable on the downshifts, than the upshifts.
This is the Fuchs oil I had been using. Its German.
Nothing fancy, but it worked great for me.
You really expect that under that kind of pressure you can do a perfect 1-2 shift?
Once you mod the suspension (torque arm, LCA's, LCA relocation kit, pan hard, shocks and drag swaybar) the car will have an easier time going straight, but back when mine was stock, half the concentration was gaining traction and half was keeping the car straight all in the short time it takes to hit 6k rpm in 1st. Hence why it takes a LOT of practice.
With heated 315 nittos, a clutch drop at 4k and a near perfect launch, I finally pulled a 1.9 60 ft, the near perfect 1-2 shift in which I chriped that shift HARD and chirped the 2-3 shift and SCREWED UP the 3-4 shift on account of a sweaty hand. Managed a 12.9 on that pass, but I imagine if I didn't mess up I had a mid 12 or lower in the making. After that the nittos were dead and couldn't do better than a 2.2 60 ft.
It's harder to shift on track than it is in normal driving. I've got 2 friends that have driven stick for a good 10+ years while I've only driven stick for 4 years officially, 3 years with this car. Yet neither have come close to attempting the speed shifts and power shifts I can do. 100+ track runs will teach you a lot.
Once you mod the suspension (torque arm, LCA's, LCA relocation kit, pan hard, shocks and drag swaybar) the car will have an easier time going straight, but back when mine was stock, half the concentration was gaining traction and half was keeping the car straight all in the short time it takes to hit 6k rpm in 1st. Hence why it takes a LOT of practice.
With heated 315 nittos, a clutch drop at 4k and a near perfect launch, I finally pulled a 1.9 60 ft, the near perfect 1-2 shift in which I chriped that shift HARD and chirped the 2-3 shift and SCREWED UP the 3-4 shift on account of a sweaty hand. Managed a 12.9 on that pass, but I imagine if I didn't mess up I had a mid 12 or lower in the making. After that the nittos were dead and couldn't do better than a 2.2 60 ft.
It's harder to shift on track than it is in normal driving. I've got 2 friends that have driven stick for a good 10+ years while I've only driven stick for 4 years officially, 3 years with this car. Yet neither have come close to attempting the speed shifts and power shifts I can do. 100+ track runs will teach you a lot.
I managed 1.8x on 245 Nittos, and 1.7x MT DR's. I dont think Ive ever missed a 1-2 shift. Its not that hard really, unless you have a very dodgy seat or driving position.
I hope that if I can get to a decent track, and my rear ARB works....I can get 60fts down to the 1.5x range. The tracks I race at dont always prep the surface though, which is crap.
And powershifting a syncro box is asking for something to break.
02-06-2008, 02:48 PM
#22
driving in the city with no precise timing is one thing
Driving at the track and shifting in under a second at high rpm while the car is slamming you in your seat is another.
On a good hook with little wheel spin, the car slams you into your seat pretty hard all the way to redline at the same time you are fighting the steering wheel to keep straight. You really expect that under that kind of pressure you can do a perfect 1-2 shift?
Once you mod the suspension (torque arm, LCA's, LCA relocation kit, pan hard, shocks and drag swaybar) the car will have an easier time going straight, but back when mine was stock, half the concentration was gaining traction and half was keeping the car straight all in the short time it takes to hit 6k rpm in 1st. Hence why it takes a LOT of practice.
With heated 315 nittos, a clutch drop at 4k and a near perfect launch, I finally pulled a 1.9 60 ft, the near perfect 1-2 shift in which I chriped that shift HARD and chirped the 2-3 shift and SCREWED UP the 3-4 shift on account of a sweaty hand. Managed a 12.9 on that pass, but I imagine if I didn't mess up I had a mid 12 or lower in the making. After that the nittos were dead and couldn't do better than a 2.2 60 ft.
It's harder to shift on track than it is in normal driving. I've got 2 friends that have driven stick for a good 10+ years while I've only driven stick for 4 years officially, 3 years with this car. Yet neither have come close to attempting the speed shifts and power shifts I can do. 100+ track runs will teach you a lot.
Driving at the track and shifting in under a second at high rpm while the car is slamming you in your seat is another.
On a good hook with little wheel spin, the car slams you into your seat pretty hard all the way to redline at the same time you are fighting the steering wheel to keep straight. You really expect that under that kind of pressure you can do a perfect 1-2 shift?
Once you mod the suspension (torque arm, LCA's, LCA relocation kit, pan hard, shocks and drag swaybar) the car will have an easier time going straight, but back when mine was stock, half the concentration was gaining traction and half was keeping the car straight all in the short time it takes to hit 6k rpm in 1st. Hence why it takes a LOT of practice.
With heated 315 nittos, a clutch drop at 4k and a near perfect launch, I finally pulled a 1.9 60 ft, the near perfect 1-2 shift in which I chriped that shift HARD and chirped the 2-3 shift and SCREWED UP the 3-4 shift on account of a sweaty hand. Managed a 12.9 on that pass, but I imagine if I didn't mess up I had a mid 12 or lower in the making. After that the nittos were dead and couldn't do better than a 2.2 60 ft.
It's harder to shift on track than it is in normal driving. I've got 2 friends that have driven stick for a good 10+ years while I've only driven stick for 4 years officially, 3 years with this car. Yet neither have come close to attempting the speed shifts and power shifts I can do. 100+ track runs will teach you a lot.
On 275 Nittos and mediocre track prep, I pulled a 1.78 60' with 386/344, and I'm not an awesome driver yet.
What gears are you running?
02-06-2008, 03:15 PM
#23
Just something to think about. Check to make sure your motor mounts and tranny mount are ok. Oh, and a Pro-Shifted trans does wonders for up shifting on these LS1 hydraulics, almost feels like I'm back in an LT1
02-06-2008, 05:50 PM
#24
let's put it this way, I'm running the damn stock 10 bolt with 3.42 gears. Anything more than a 1.9 and I'm probably towing it home. I know a few that have cut 1.7-1.8 and were on the verge of shattering the gears on inspection after they started hearing noises out the rear.
Each launch at 4k makes me wonder if this is the launch that kills it. I was also running stock shocks. I just swapped them out and hopefully I'll cut the wheel spin down. I also have a torque arm on order as well as I was running the stocker and god knows how much that thing can flex under load.
Each launch at 4k makes me wonder if this is the launch that kills it. I was also running stock shocks. I just swapped them out and hopefully I'll cut the wheel spin down. I also have a torque arm on order as well as I was running the stocker and god knows how much that thing can flex under load.
02-07-2008, 08:03 AM
#25
let's put it this way, I'm running the damn stock 10 bolt with 3.42 gears. Anything more than a 1.9 and I'm probably towing it home. I know a few that have cut 1.7-1.8 and were on the verge of shattering the gears on inspection after they started hearing noises out the rear.
Each launch at 4k makes me wonder if this is the launch that kills it. I was also running stock shocks. I just swapped them out and hopefully I'll cut the wheel spin down. I also have a torque arm on order as well as I was running the stocker and god knows how much that thing can flex under load.
Each launch at 4k makes me wonder if this is the launch that kills it. I was also running stock shocks. I just swapped them out and hopefully I'll cut the wheel spin down. I also have a torque arm on order as well as I was running the stocker and god knows how much that thing can flex under load.
And yeah, even the 4K launches are most likely going to eat that rear up pretty soon.
02-07-2008, 08:06 AM
#26
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I know you said the short stick caused too much noise, which is definitely the case, but was shifting effort at cruise noticeably different?
Another question, is this just 1-2, or through all the gears? I know that your car doesn't have the electrical hookup, but did your trans still have the skip shift solenoid in it? It shouldn't be actuated at all, but I wonder if it's somehow getting in the way?
02-07-2008, 11:15 AM
#27
The solenoid isn't hooked up but it's still there. I looked at it's function when I rebuilt the tranny and it's not in the way.
Actually it shifts smooth, but I have to let the synchro clutches work before I can complete the shift.
When I rebuilt the tranny (4000 miles ago) I also installed a new stock clutch and a new slave cylinder. I also replaced the pilot bearing with a bronze bushing.
The drill mod is done and the master is a modified stock piece (adjustable).
There is no air in the system, I could feel that if there was any.
I bled the hydraulics before filling the tranny and installing the driveshaft. I then had a friend pushing on the clutch pedal, shift in 1st and with an old yoke installed in the tranny rear I was able to turn it by hand with no effort = the clutch disengages completely and the engine is completely separated from the tranny (engine turned off
)Maybe it's too soon? Maybe I need to wait a while under the new clutches adapt themselves to the tranny parts? Now it's all carbon stuff from Six Speeds Inc.
02-07-2008, 12:22 PM
#29
9 Second Club
My tranny was shifting fine with a few hundred miles on it ( after some clutch/ARP bolt issues )
When driving normally, my shifts certainly arent quick, but they have no need to be. But when I want to change gear hard, it isnt a problem either.
Have you tried being a little more aggressive with it ? Is it really that hard to get change ?
Are upshifts and downshifts the same ?
When driving normally, my shifts certainly arent quick, but they have no need to be. But when I want to change gear hard, it isnt a problem either.
Have you tried being a little more aggressive with it ? Is it really that hard to get change ?
Are upshifts and downshifts the same ?
02-07-2008, 03:00 PM
#33
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I have seen more of an improvement in my shifting with simple practice, more then anything else.
However;
I think a good clutch that can engage/disengage rapidly will allow for a much faster shift. My tranny is stock, with a stock Pro-5.0 shifter, with factory GM ATF fluid in it. And I think I shift pretty damn fast. What I think it irrelevant however, I have been told that I shift very fast.
The only think I attribute to it is clutch, and practice practice practice, oh yeah, and more practice.
However;
I think a good clutch that can engage/disengage rapidly will allow for a much faster shift. My tranny is stock, with a stock Pro-5.0 shifter, with factory GM ATF fluid in it. And I think I shift pretty damn fast. What I think it irrelevant however, I have been told that I shift very fast.
The only think I attribute to it is clutch, and practice practice practice, oh yeah, and more practice.
02-07-2008, 03:49 PM
#34
I really feel that I'm forcing the rings against the gears to stop them and I don't like it.
Maybe it's just the oil... too slipppery? I'll try another product as soon as I can.
Downshift is worst, it takes longer (and yes, I go shortly on the gas to match the rpm).
I also tried the "5000 rpm test" (put the car on a flat surface, desingege the clutch, select 1st gear and rev it up to 5000 rpm). The car didin't move.
Fran: I didn't ask the parts supplier. I didn't want to hear stuff like who made the insatllation, have you checked the tolerances, is the clutch installed properly, have you bleed the hydraulics, send us back the parts to check them... All in all it shift better than before, but I was expecting something different. I also ordered a new master but the old one is still ok (to my poor knowledge) and I haven't installed it.
02-07-2008, 03:50 PM
#35
If anything low rpm shifting with good rev matching should slide like butter. If I want to out accelerate cars with the revs down I usually speed shift pretty quick from 1-2 and 2-3. With no body jarring that's a pretty much bang bang type shift under 3k. Even above that, it only becomes tricky at 6k+.
Can you do a FAST 1-2 shift off the line at say 3k similar to how you can pull a 3-4 shift? I say that because the 3-4 shift is probably the fastest shift you can pull off, even at speed or at WOT. If you find that the 3-4 shift is significantly faster or that 1-2 grinds or blocks you a little, you may have issues with the clutch or syncros. I'd rebleed to be sure.
Can you do a FAST 1-2 shift off the line at say 3k similar to how you can pull a 3-4 shift? I say that because the 3-4 shift is probably the fastest shift you can pull off, even at speed or at WOT. If you find that the 3-4 shift is significantly faster or that 1-2 grinds or blocks you a little, you may have issues with the clutch or syncros. I'd rebleed to be sure.
02-07-2008, 04:01 PM
#36
9 Second Club
If you jack the rear of the car up ( and mount securely on axle stands of course ), and put it in gear with the clutch pedal depressed....do the rear wheels turn ?
), and put it in gear with the clutch pedal depressed....do the rear wheels turn ?
02-08-2008, 05:11 AM
#38
If anything low rpm shifting with good rev matching should slide like butter. If I want to out accelerate cars with the revs down I usually speed shift pretty quick from 1-2 and 2-3. With no body jarring that's a pretty much bang bang type shift under 3k. Even above that, it only becomes tricky at 6k+.
Can you do a FAST 1-2 shift off the line at say 3k similar to how you can pull a 3-4 shift? I say that because the 3-4 shift is probably the fastest shift you can pull off, even at speed or at WOT. If you find that the 3-4 shift is significantly faster or that 1-2 grinds or blocks you a little, you may have issues with the clutch or syncros. I'd rebleed to be sure.
Can you do a FAST 1-2 shift off the line at say 3k similar to how you can pull a 3-4 shift? I say that because the 3-4 shift is probably the fastest shift you can pull off, even at speed or at WOT. If you find that the 3-4 shift is significantly faster or that 1-2 grinds or blocks you a little, you may have issues with the clutch or syncros. I'd rebleed to be sure.
All synchros are new (carbon), included a 3-4 fork (steel), billet keys and pads (bronze).
The clutch was well prepared for the install: splines deburred, cleaned and slightly greased. Clutch surface, flywheel + PP degreased.
The flywheel bolts are sealed with a little RTV to avoid oil coming through the threads. New rear block seal too.
The bronze bushing has been filled with tranny oil before installation.
Another thing: i have the stock Throttle Cracker tables. This allows the engine to reduce speed slowly to avoid lash shake when you remove the engine load (lift the right foot).
I can make the engine to decel faster if I zero the table. Shifting is much better then.
Is that something you guys do to improve shifting? To mess with those tables?
The idle vacuum is fine 28-30 kPa, no vacuum leaks that would allow a slow rpm drop.
...I hear you guys that say to flush the hydraulics again... I'll try that too.
Stefano
02-08-2008, 08:05 AM
#40
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...Another thing: i have the stock Throttle Cracker tables. This allows the engine to reduce speed slowly to avoid lash shake when you remove the engine load (lift the right foot).
I can make the engine to decel faster if I zero the table. Shifting is much better then.
Is that something you guys do to improve shifting? To mess with those tables?
I can make the engine to decel faster if I zero the table. Shifting is much better then.
Is that something you guys do to improve shifting? To mess with those tables?