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More power + poor shifting = slower times

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Old Apr 16, 2007 | 05:03 AM
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C6C6CH3vo's Avatar
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More power + poor shifting = slower times

My launch was good - 1.724 60' - but since I really haven't launched it with the recent mods/tuning I was a little light headed from the experience and short shifted to 2nd by about 1000rpm (6200 rpm). I also short shifted 3rd by 800rpm (6500rpm)

Worst of all my 1st - 2nd shift was 0.82 seconds
and 2nd - 3rd was 0.67 seconds, a total of 1.52 seconds of my drag run was spent with foot off throttle!

I also thought the time billboards was the finish line (finish was about 0.2 sec beyond billboard) so I ended up coasting through the actual finish 0.2 seconds later.

My car is just so difficult to shift, especially to 2nd, and gets even more difficult at higher rpms, which is why the short shifting and slow shifts.


60'... 1.724
1/8... 8.426
MPH.. 84.07

04 with cams and methanol






Here is the kicker, I ran 8.03 sec @ 89 MPH in 1/8th with same car a year ago with about 60 whp less - lol .

So let me restress importance of shift points and quickness - you don't want the timer clicking away while your trying to find the gear
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Old Apr 16, 2007 | 05:52 AM
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Why is it so difficult to shift? What type of a clutch are you running?
I'm sure you just need some more time with the car.
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Old Apr 16, 2007 | 06:02 AM
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So when you say difficult do you mean your shifter is getting locked out at high RPM's?
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Old Apr 16, 2007 | 06:18 AM
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dont take your foot off the gas pedel.... leave it at full throttle, kick the clutch in as quick as you can and rip it in the next gear.
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Old Apr 16, 2007 | 06:19 AM
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sounds like someone needs poly motor mounts
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Old Apr 16, 2007 | 06:59 AM
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Originally Posted by Planet Evo
Why is it so difficult to shift? What type of a clutch are you running?

Excedy S1 ($375), but the stock clutch gave me same trouble and higher RPM shifts are worse

I'm sure you just need some more time with the car.
I have 43,000 miles exp with the car. Also, last year I had a friend of mine drive it and had the same problem with it on 1 - 2, and he had an 03 VIII, even worse - drives GT3 Porshe for a living. Car has always been a troublesome shifting, it's just funny how over time I shift over cautiously to avoid a lock out.


Originally Posted by whtrice
So when you say difficult do you mean your shifter is getting locked out at high RPM's?
Yeah, worse as rpm goes up, 1 - 2 is the most troublesome and the faster I shift (and higher rpm) the more force it takes to go in

Originally Posted by Ralliart_on_LSD
dont take your foot off the gas pedel.... leave it at full throttle, kick the clutch in as quick as you can and rip it in the next gear.
I would need to find a car rental to practice that one, but worth a try

Originally Posted by mifesto
sounds like someone needs poly motor mounts
My mounts did take a beating when I changed the clutch. Have you tried this with success?
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Old Apr 16, 2007 | 07:22 AM
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yea keeping ytour foot on the throttle like that lets you bang the gears out super quick, and you have almost no turbo lag what so ever....
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Old Apr 16, 2007 | 08:56 AM
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From: Secret Tweaker Pad
Originally Posted by Ralliart_on_LSD
yea keeping ytour foot on the throttle like that lets you bang the gears out super quick, and you have almost no turbo lag what so ever....
If you arent a pro at no lift shifting all it will lead to is a broke car or a slower 1/4 mile time. It definitely takes a good deal of practice to get good at.
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Old Apr 16, 2007 | 09:36 AM
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If the physical shift is the same speed and the clutch holds the power a NLS will never be slower than a granny shift.
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Old Apr 16, 2007 | 09:43 AM
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how would that be slower???
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Old Apr 16, 2007 | 09:55 AM
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From: Secret Tweaker Pad
Originally Posted by Jasil
If the physical shift is the same speed and the clutch holds the power a NLS will never be slower than a granny shift.
That is true but all I was pointing out is that if you dont have a lot of practice at it a NLS just isnt going to happen. Unless he shifts a lot faster its just going to equal over rev or bouncing off the rev limiter.
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Old Apr 16, 2007 | 10:06 AM
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i dont think its that hard. i tought myself and did it perfect the first time, been doin it ever since... im at a redlight, i rev to 3 grand, jam it in first, and take off, who needs a clutch???

nah just kidding... but i do NLS and i did teach myself... never had a problem and i think its the ONLY way to shift at the track... of course it cant be healthy for the car, which is only why i only do it 2-3, 3-4 and 4=5 if needed... i granny shift 1-2... i never had anhy problems with the way i do it tho, and its drastically better at the track
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Old Apr 16, 2007 | 12:02 PM
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Originally Posted by C6C6CH3vo
My mounts did take a beating when I changed the clutch. Have you tried this with success?
I have almost 60k mi on my car fyi. I've never got lock out but lately there just seemed to be some added resistance before I shift into the next gear during a high rev run. I've adjusted the clutch and I change the trans fluid quite often. Driving normally the shifts are like butter. I'll also mention I've owned 4 previous 1g and 2g DSMs so I know what a notchy transmission can feel like. So this last week I decided to pick up the front poly motor mount from AMS and installed it this weekend. I have no other driveline mods I might add such as shifter bushings(linkage/shifter base), ss line, or short shifter. Just running the HD ACT street clutch with the restricter removed. I went out for a little road test and right away I could feel an improvement. So I logged some runs and here's what I found.

Before shift times:

1/2= .55s

2/3= .42s

3/4= .40s

After:

1/2= .40s (.15s improvement)

2/3= .34s (.08s improvement)

3/4= .40s (No improvement from before)

Total time reduction: ~.23s

The before times were taken from my previous track visit. The after was just an average of two pulls I ran on the street so I'm hoping with more seat time I can improve, even if its just a couple more hundredths shaved off. I would definitely recommend at least trying a front motor mount replacement. I intend to try some of the bushing upgrades, ss line, etc and note their improvements also.
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Old Apr 16, 2007 | 12:40 PM
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From: sc
I'll have to look in to those poly mounts.

Another couple things to point out are that my 3 -4's and 4 -5's are smooth, like 0.30 sec 3 -4, haven't gone fast enough for high rpm 4 -5.

Also note I didn't use a low stationary rev limiter for the launch, I just started revving and sent it up to 6K at the green xmas light so my only knock was one count while staged
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Old Apr 16, 2007 | 01:34 PM
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Very nice,

this is how i log my passes too!

i use the TPS column and the log time in secs from evoscan...

100% TPS - lift gearchange - 100% TPS... the time in between is the time of the gas...

i always lift off completely because i am on the stock clutch and stock clutch line!

Fast shifting is half the game on the strip...

In my first 4 passes ever with the Evo i averaged 0.4 second shifts in all four passes, except an amazing 0.2 second change from 2nd to 3rd gear which actually is crazy because its probably the most difficult shift in the pass...

So doing 3 changes in the 1/4 mile 0.4 secs on average thats 1.2 secs in gearchanges...

Now if i manage to do the 0.2sec gearchanges in all 3 gearchange i can save 0.6 secs in the pass which can get me well in to the 11s!!!
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