Shift kit worth it?
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,089
Likes: 819
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
Shift kit worth it?
Not a fan of the soft shifts with the trans in OD. In D, they are noticeably firmer. That's why I only use OD on the highway. I know a shift kit will firm up shifts. But will it only firm them up at WOT, or part throttle as well? Will it still shift at the same RPM/Speed when at WOT, and part throttle? With a shift kit, does the factory settings for TV stay the same? Because I was reading that it increases line pressure? Since the trans in my 93 was rebuilt May 2015, I just want to get the longest life out of it. And I understand that firmer shifts put less wear on the clutches. The trans is not a 4L60E, it's called a 4L60 in the FSM. Basically a 700R4. Only pointing that out because most think 93's have a 4l60e.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Because trans was just rebuilt you should talk to rebuilder. See what he thinks of shift quality. Sometimes shift improver kit are installed during the rebuild. Also if someone tweaks trans and causes a failure; rebuilder is unlikely to stand behind it. Most the time shift kits are worth it, unless trans is already hurt. Most kits will cause clutches/bands apply quicker with more pressure or less dampening by removing check *****, enlarging apply orifices in spacer plate, changing springs, removing springs, disabling accumulators, etc. With electric shift it would be software and possibly component upgrades.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,089
Likes: 819
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
Because trans was just rebuilt you should talk to rebuilder. See what he thinks of shift quality. Sometimes shift improver kit are installed during the rebuild. Also if someone tweaks trans and causes a failure; rebuilder is unlikely to stand behind it. Most the time shift kits are worth it, unless trans is already hurt. Most kits will cause clutches/bands apply quicker with more pressure or less dampening by removing check *****, enlarging apply orifices in spacer plate, changing springs, removing springs, disabling accumulators, etc. With electric shift it would be software and possibly component upgrades.
Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
Quicker apply or release means reduced wear of bands and clutches. The 3-4 shift is not known to be harsh. Maybe because of the rear axle ratios. WOT shift into 4th is well over 120 mph in stock form.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,089
Likes: 819
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
I think the fastest I have been in this car is 120
Yea, I don't remember a 3-4 shift being harsh in my other auto c4. I don't want the tires chirping at part throttle, just want them firmer. 1-2 shift is firm with trans in D. It'll sometimes chirp tires into 2nd with gear selector in D. All other are soft at part throttle.
Yea, I don't remember a 3-4 shift being harsh in my other auto c4. I don't want the tires chirping at part throttle, just want them firmer. 1-2 shift is firm with trans in D. It'll sometimes chirp tires into 2nd with gear selector in D. All other are soft at part throttle.
Thread Starter
Race Director
Joined: Oct 2011
Posts: 16,089
Likes: 819
From: Dallas Texas
2025 C4 of the Year Finalist - Modified
I think the fastest I have been in this car is 120 Yea, I don't remember a 3-4 shift being harsh in my other auto c4. I don't want the tires chirping at part throttle, just want them firmer. 1-2 shift is firm with trans in D. It'll sometimes chirp tires into 2nd with gear selector in D. All other are soft at part throttle.
Yea, I don't remember a 3-4 shift being harsh in my other auto c4. I don't want the tires chirping at part throttle, just want them firmer. 1-2 shift is firm with trans in D. It'll sometimes chirp tires into 2nd with gear selector in D. All other are soft at part throttle.
Team Owner
Joined: Jul 2004
Posts: 28,462
Likes: 3,288
From: Hartford WI
IMO with that much mileage, unless most of it was highway miles, I really wouldn't want to waste my money. I would do it all when I rebuild or just rebuild now and have it included.
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Le Mans Master
Joined: Sep 2013
Posts: 6,192
Likes: 750
From: near the thumb in the mitten
With a 4l60e a shift kit would be more of reprogramming transmission operation in PCM . There maybe some minor changes to spacer plate, but I not certain it's worth doing by itself. Reprogramming would change shift timing and feel and where I would start first.
Burning Brakes
Joined: Dec 2005
Posts: 805
Likes: 11
From: Hickory Flat Ga
You can program shift characterustics in the PCM. The major advantage of a shift kit is manual operation. Harmless downshifts and rifle shot upshifts are why it;s installed. It changed my car dramatically.
Pro
Joined: Apr 1999
Posts: 533
Likes: 6
From: Poinciana Florida
Tcs
Why don't you consider a SONIC throttle cable spring. It increases tv pressure a moderate amount and may be all you need.
For about $5.00 cost and about$6.00 shipping it's worth the effort.
It takes about 2 minutes to install--unless you drop it. Look up PATC transmissions to order.
For about $5.00 cost and about$6.00 shipping it's worth the effort.
It takes about 2 minutes to install--unless you drop it. Look up PATC transmissions to order.
