I put it down the Drag strip
Registered User
Joined: Oct 2003
Posts: 795
Likes: 0
From: Oz
Do you pull the stick hard into the gears? Has it always been this good or did it get better as it was run it a bit?
The gearbox has loosend up a little bit over the last 4 months (ie. not as stiff anymore), but I'd say that it was always quick and positive.
The 2nd to 3rd gear-change surprises me the most ... the speed that you can slam it throught the gate without the box baulking is incredible. I pressumed that the box has really good and strong synchros.
The gearbox has loosend up a little bit over the last 4 months (ie. not as stiff anymore), but I'd say that it was always quick and positive.
The 2nd to 3rd gear-change surprises me the most ... the speed that you can slam it throught the gate without the box baulking is incredible. I pressumed that the box has really good and strong synchros.
Thread Starter
Registered User
Joined: Mar 2003
Posts: 181
Likes: 0
From: Sydney Australia
Originally posted by DavidM
Changed up at around 5800 each time, slight spin into 2nd gear.
I think this could be the reason for the low trap speed (ie. missing 5kph+). You had another 800rpm of revs to go in each gear. Loosing that rpm in 3 gears will loose you a lot of speed. If you want maximum performance, then you need to get close to the redline. Think of it this way - at 6000rpm in 1st gear you will have a lot more pull than in 2nd at 3600rpm (ie. revs you drop to when changing at 5800rpm). I'd guess that you'd loose at least 1/2 a car length on each gear-change becuase you are shortshifting ... maybe even more.
265/40 rears reduced to 25lb/sq". Stripped car but 3/4 tank full.
Any idea what 25lb/sq" is in psi? Also what do you mean by 'stripped car'?
Errr... lb sq " = p s i !!!
I din't want to hit cut out, so upshifted at what is reckoned to be max torque, 5800 rpm.
Stripped..I meant took out lap tap, brief case, spare clothes and spare wheel!
Ta for comments, vertical learning curve here.
4WSboy
60' 2.221
That's not bad, but 2.0sec is what you're aiming for. Maybe even high 1.9s. From what 'they' say, 0.2sec gained at the launch is equal to 0.4sec gained at the end of the 1/4mile.
ET 14.449secs 96.66 mph (155.56K)
So if you're going again, 1st thing to do is take it to the redline and hope for trap-speed of 160kph+. Once you're getting 160kph+ out of the car then you know that you're driving the car to it's potential (even if your time is not showing it).
Changed up at around 5800 each time, slight spin into 2nd gear.
I think this could be the reason for the low trap speed (ie. missing 5kph+). You had another 800rpm of revs to go in each gear. Loosing that rpm in 3 gears will loose you a lot of speed. If you want maximum performance, then you need to get close to the redline. Think of it this way - at 6000rpm in 1st gear you will have a lot more pull than in 2nd at 3600rpm (ie. revs you drop to when changing at 5800rpm). I'd guess that you'd loose at least 1/2 a car length on each gear-change becuase you are shortshifting ... maybe even more.
265/40 rears reduced to 25lb/sq". Stripped car but 3/4 tank full.
Any idea what 25lb/sq" is in psi? Also what do you mean by 'stripped car'?
Errr... lb sq " = p s i !!!
I din't want to hit cut out, so upshifted at what is reckoned to be max torque, 5800 rpm.
Stripped..I meant took out lap tap, brief case, spare clothes and spare wheel!
Ta for comments, vertical learning curve here.
4WSboy
60' 2.221
That's not bad, but 2.0sec is what you're aiming for. Maybe even high 1.9s. From what 'they' say, 0.2sec gained at the launch is equal to 0.4sec gained at the end of the 1/4mile.
ET 14.449secs 96.66 mph (155.56K)
So if you're going again, 1st thing to do is take it to the redline and hope for trap-speed of 160kph+. Once you're getting 160kph+ out of the car then you know that you're driving the car to it's potential (even if your time is not showing it).
Thread Starter
Registered User
Joined: Mar 2003
Posts: 181
Likes: 0
From: Sydney Australia
Originally posted by KY350
As David said, shortshifting at 5800 revs would cost you a lot of time over the quater. Keep in mind that on each gear change, you want to drop the revs into the max torque band, that is 4800rpm. Changing at 5800rpm would mean that the revs in 2nd gear would be much lower than max torque.
Also, I find that TC reduces power enourmously. Without it, I always break traction momentarily on the 1-2 gear change, but it hauls a$$ when it regains traction. With TC on, no loss of traction, but no power to wheels either. It seems to take an eternity to get back up to 6000+ rpm.
You say that your launch may not have been perfect. With approximately 350Nm to control at 4500rpm, i'm not surprised that you may have had a little trouble getting off the line smartly. I rarely launch with more than 2500rpm because the torque curve is so flat, that there is at least 300Nm at this rpm. Controlling that amount of torque through the wheels and onto the bitchumen is not a simple task. Try launching at lower revs in a quiet street and see how you go. Try 4000rpm, then 3500rpm, 3000rpm etc and see where you get the best launch. Then take that to the track, together with 6400 rpm gear changes (set your rpm limit at 6400 and the light will flash at 5900 rpm to warn you to change gears) and I bet you will see low 14's.
DavidM, I think "stripped" means he removed spare / jack / tools etc to lighten the car as much as possible.
BTW, we should set a date to go to the drags together and compare times. I'm in for any Wed night.
As David said, shortshifting at 5800 revs would cost you a lot of time over the quater. Keep in mind that on each gear change, you want to drop the revs into the max torque band, that is 4800rpm. Changing at 5800rpm would mean that the revs in 2nd gear would be much lower than max torque.
Also, I find that TC reduces power enourmously. Without it, I always break traction momentarily on the 1-2 gear change, but it hauls a$$ when it regains traction. With TC on, no loss of traction, but no power to wheels either. It seems to take an eternity to get back up to 6000+ rpm.
You say that your launch may not have been perfect. With approximately 350Nm to control at 4500rpm, i'm not surprised that you may have had a little trouble getting off the line smartly. I rarely launch with more than 2500rpm because the torque curve is so flat, that there is at least 300Nm at this rpm. Controlling that amount of torque through the wheels and onto the bitchumen is not a simple task. Try launching at lower revs in a quiet street and see how you go. Try 4000rpm, then 3500rpm, 3000rpm etc and see where you get the best launch. Then take that to the track, together with 6400 rpm gear changes (set your rpm limit at 6400 and the light will flash at 5900 rpm to warn you to change gears) and I bet you will see low 14's.
DavidM, I think "stripped" means he removed spare / jack / tools etc to lighten the car as much as possible.
BTW, we should set a date to go to the drags together and compare times. I'm in for any Wed night.
You say "drop the revs to max torque band of 4800 on upshift" but then you say "together with 6400 rpm upchanges"
Ta...
Steve
Registered User
Joined: Oct 2003
Posts: 795
Likes: 0
From: Oz
I didn't want to hit cut out, so upshifted at what is reckoned to be max torque, 5800 rpm.
That is not thr quickest way to accelerate. Look at the power curve you are riding when shifting at 5800rpm:
- 0-54kph (3000-5800rpm in 1st gear) = 105-200kW
- 54-86kph = (3600-5800rpm in 2nd gear) = (125-200kW) * .63 = 79-126kW
- 86-125kph = (4000-5800rpm in 3rd gear) = (145-200kW) * .44 = 63-88kW
- 125-158kph = (4600-5800rpm in 4rd gear) = (165-200kW) * .34 = 57-68kW
So while shifting at 5800rpm you are riding the power curve between:
- 105 -> 200kW @ 0-54kph
- 79 -> 126kW @ 54-86kph
- 63 -> 88kW @ 86-125kph
- 57 -> 68kW @ 125-158kph
On the other hand shifting at 6600rpm (ie redline) will see you riding this power curve:
- 0-58kph (3000-6200rpm in 1st gear) = 105-206kW
- 58-62kph (6200-6600rpm in 1st gear) = 206-185kW
- 62-92kph = (4200-6200rpm in 2nd gear) = (145-206kW) * .63 = 91-130kW
- 92-98kph = (6200-6600rpm in 2nd gear) = (206-185kW) * .63 = 130-117kW
- 98-133kph = (4600-6200rpm in 3rd gear) = (165-206kW) * .44 = 73-91kW
- 133-142kph = (6200-6600rpm in 3rd gear) = (205-185kW) * .44 = 91-81kW
- 142-169kph = (5200-6200rpm in 4rd gear) = (185-206kW) * .34 = 63-70kW
So while shifting at 6600rpm you are riding the power curve between:
- 105 -> 206 -> 185kW @ 0-62kph
- 91 -> 130 -> 117kW @ 62-98kph
- 73 -> 91 -> 81kW @ 98-142kph
- 63 -> 70kW @ 142-169kph
So as you can see, shifting at 6600rpm is putting a lot more power to the ground that shifting at 5800rpm. That in turn will make you quicker (and probably make up thos e'missing' 5kph of terminal velocity at the end of 1/4 mile).
Shifting as close to redline as possible is the quickest way to accelerate in the Zed.
Errr... lb sq " = p s i !!!
Thanks for that.
Stripped..I meant took out lap tap, brief case, spare clothes and spare wheel!
Thanks for that as well.
That is not thr quickest way to accelerate. Look at the power curve you are riding when shifting at 5800rpm:
- 0-54kph (3000-5800rpm in 1st gear) = 105-200kW
- 54-86kph = (3600-5800rpm in 2nd gear) = (125-200kW) * .63 = 79-126kW
- 86-125kph = (4000-5800rpm in 3rd gear) = (145-200kW) * .44 = 63-88kW
- 125-158kph = (4600-5800rpm in 4rd gear) = (165-200kW) * .34 = 57-68kW
So while shifting at 5800rpm you are riding the power curve between:
- 105 -> 200kW @ 0-54kph
- 79 -> 126kW @ 54-86kph
- 63 -> 88kW @ 86-125kph
- 57 -> 68kW @ 125-158kph
On the other hand shifting at 6600rpm (ie redline) will see you riding this power curve:
- 0-58kph (3000-6200rpm in 1st gear) = 105-206kW
- 58-62kph (6200-6600rpm in 1st gear) = 206-185kW
- 62-92kph = (4200-6200rpm in 2nd gear) = (145-206kW) * .63 = 91-130kW
- 92-98kph = (6200-6600rpm in 2nd gear) = (206-185kW) * .63 = 130-117kW
- 98-133kph = (4600-6200rpm in 3rd gear) = (165-206kW) * .44 = 73-91kW
- 133-142kph = (6200-6600rpm in 3rd gear) = (205-185kW) * .44 = 91-81kW
- 142-169kph = (5200-6200rpm in 4rd gear) = (185-206kW) * .34 = 63-70kW
So while shifting at 6600rpm you are riding the power curve between:
- 105 -> 206 -> 185kW @ 0-62kph
- 91 -> 130 -> 117kW @ 62-98kph
- 73 -> 91 -> 81kW @ 98-142kph
- 63 -> 70kW @ 142-169kph
So as you can see, shifting at 6600rpm is putting a lot more power to the ground that shifting at 5800rpm. That in turn will make you quicker (and probably make up thos e'missing' 5kph of terminal velocity at the end of 1/4 mile).
Shifting as close to redline as possible is the quickest way to accelerate in the Zed.
Errr... lb sq " = p s i !!!
Thanks for that.
Stripped..I meant took out lap tap, brief case, spare clothes and spare wheel!
Thanks for that as well.
Registered User
Joined: Apr 2003
Posts: 719
Likes: 0
From: Sydney, Australia
4WSboy - if you change up gears at 6400 - 6600rpm as opposed to 5800rpm, then once in the higher gear, you will find the revs only drop to about 4500 - 4800rpm (not below 4000 as you are experiencing now), which is in the meatiest portion of the torque curve and will yield the best acceleration (push in the back).
I tend to shift by sound rather than by sight, but I do ocassionally peek at the tacho as sometimes I find myself a little late on the change and hitting the rev limiter - not conducive to quick passes.
I tend to shift by sound rather than by sight, but I do ocassionally peek at the tacho as sometimes I find myself a little late on the change and hitting the rev limiter - not conducive to quick passes.
Thread Starter
Registered User
Joined: Mar 2003
Posts: 181
Likes: 0
From: Sydney Australia
Originally posted by KY350
4WSboy - if you change up gears at 6400 - 6600rpm as opposed to 5800rpm, then once in the higher gear, you will find the revs only drop to about 4500 - 4800rpm (not below 4000 as you are experiencing now), which is in the meatiest portion of the torque curve and will yield the best acceleration (push in the back).
I tend to shift by sound rather than by sight, but I do ocassionally peek at the tacho as sometimes I find myself a little late on the change and hitting the rev limiter - not conducive to quick passes.
4WSboy - if you change up gears at 6400 - 6600rpm as opposed to 5800rpm, then once in the higher gear, you will find the revs only drop to about 4500 - 4800rpm (not below 4000 as you are experiencing now), which is in the meatiest portion of the torque curve and will yield the best acceleration (push in the back).
I tend to shift by sound rather than by sight, but I do ocassionally peek at the tacho as sometimes I find myself a little late on the change and hitting the rev limiter - not conducive to quick passes.
Can't fail next time!!
Steve
Registered User
Joined: Nov 2002
Posts: 1,934
Likes: 0
From: Sydney Australia
Anyone go to WSID last night?
I just found out my old car ran last night. 12.9 @ 106mph
Not bad for a hairdressers car on the drivers first outing. Thought it might be of interest for comparisons sake.
I just found out my old car ran last night. 12.9 @ 106mph
Not bad for a hairdressers car on the drivers first outing. Thought it might be of interest for comparisons sake.
Registered User
Joined: Apr 2003
Posts: 719
Likes: 0
From: Sydney, Australia
Forgot it was on, but would have liked to have gone. When is the next meet there? I'd like to go and check it out before I put my car down the strip.
BTW, that's a good time for the MX5. Would be amazing around the old pacific highway if it doesn't have much lag.
BTW, that's a good time for the MX5. Would be amazing around the old pacific highway if it doesn't have much lag.
Registered User
Joined: Nov 2002
Posts: 1,934
Likes: 0
From: Sydney Australia
It's on every Wednesday.
The setup on the MX-5 had no lag, just instant wheel spin. Was a lot of fun to drive. BTW that time was with 3/4 tank, jack, spare, tools etc. I think with practice they'd get it down to mid 12s. Now I know why the Zed feels so slow.
The setup on the MX-5 had no lag, just instant wheel spin. Was a lot of fun to drive. BTW that time was with 3/4 tank, jack, spare, tools etc. I think with practice they'd get it down to mid 12s. Now I know why the Zed feels so slow.
Registered User
Joined: Apr 2003
Posts: 719
Likes: 0
From: Sydney, Australia
Don't know why you ever let that thing go Apps. Being an MX5, I'm sure it handled like nothing else and the additional power without lag makes it a dream car.
Now you need to throw $45K Nizpro's way for that kind of performance from the Z (ok, I know you can do it for less, but you are not a gineau pig via Nizpro).
Now you need to throw $45K Nizpro's way for that kind of performance from the Z (ok, I know you can do it for less, but you are not a gineau pig via Nizpro).
Registered User
Joined: Nov 2002
Posts: 1,934
Likes: 0
From: Sydney Australia
It was a great car but after 9 years with the same car I just needed a change. Not sure what I'm going to do with the Zed yet which is why I'm not rushing into ordering stuff. BTW the MX-5 had $30k+ in mods over that period.
Registered User
Joined: Nov 2002
Posts: 1,934
Likes: 0
From: Sydney Australia
I agree Nizpro are too expensive. They should be offering a base level kit without all the engine internals but they weren't interested in doing that.
I'm a little worried now. Skiddazle just posted his and another TT 1/4 times and they were both just above 13sec. He did have a slipping clutch but mentioned no other problems. I had hoped a TT Zed would be faster than that. Really not sure what to do with this car.
I'm a little worried now. Skiddazle just posted his and another TT 1/4 times and they were both just above 13sec. He did have a slipping clutch but mentioned no other problems. I had hoped a TT Zed would be faster than that. Really not sure what to do with this car.
Registered User
Joined: Apr 2003
Posts: 719
Likes: 0
From: Sydney, Australia
I'd expect low to mid 12's from a TT.
13+ sounds disappointing, but you get what you pay for.
I like the Nizpro solution of upgrading the internals considering the power / torque numbers they are getting. If their car is not a low 12s car, then I will eat my hat!
Keep in mind that the power improvements on the US TTed cars are much lower than Nizpro's.
13+ sounds disappointing, but you get what you pay for.
I like the Nizpro solution of upgrading the internals considering the power / torque numbers they are getting. If their car is not a low 12s car, then I will eat my hat!
Keep in mind that the power improvements on the US TTed cars are much lower than Nizpro's.