1985 Transmission Question
10-23-2002, 01:43 PM
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1985 Transmission Question
My car locks the converter right after if shifts to third gear which causes the engine to sound like it is lugging. I thought the converter should not lock until overdrive. If it would just wait a few hunderd more rpm before locking it would be OK.
Is there a way to adjust this?
Also, the 1-2 shift is at 5200 rpm which seems too high.
The 2-3 shift is at 4700 rpm.
What should the car shift at and how can I change the shift points?
Is there a way to adjust this?
Also, the 1-2 shift is at 5200 rpm which seems too high.
The 2-3 shift is at 4700 rpm.
What should the car shift at and how can I change the shift points?
10-23-2002, 01:46 PM
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Re: 1985 Transmission Question (DarthD)
The shift points dont sound far off, and youre right it is too high.
Id adjust the TV cable until you find some shift points you like, maybe add a shift kit. Your TC should lock whenever it hits the lockup RPM, which is higher for an 85 than other L98s (little below 2000 i think), and the ECM controls lockup in OD only.
Id adjust the TV cable until you find some shift points you like, maybe add a shift kit. Your TC should lock whenever it hits the lockup RPM, which is higher for an 85 than other L98s (little below 2000 i think), and the ECM controls lockup in OD only.
10-23-2002, 01:53 PM
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Re: 1985 Transmission Question (DarthD)
I had an '85 Z51 and the torque converter locked up half way through a turn every time just when you stepped on the throttle. Right when you don't want less torque. PO'd me right off until I put a switch in the converter lockup wiring. I'd leave it off around town and turn it on on the freeway. Then I got a Hypertech chip and it adjusted the lockup, I guess. Worked just like the '87 I have now after that. I heard they changed the chip in '86 for that reason. Then I took the switch out.
Get a good chip. It does wonders for drivabilty.
BTW, every C4 I've ever had ran out of rpm before the tranny shifted into second gear but my '85 was the worst. I had a friend who put siamed runners on his '85 and it cured that prob. I've also heard extra fuel pressure fixes that prob too but you'll need an adjustable fuel pressure regulator and a gauge for accurate measurments.
I tried adjusting the TV cable and I was able to make an improvement in the 1-2 shift but then the 3-4 shift was screwed up. Best to adjust that like the factory specifies and search for remedies elsewhere.
BIG JIM
[Modified by BIG JIM 54, 6:00 PM 10/23/2002]
Get a good chip. It does wonders for drivabilty.
BTW, every C4 I've ever had ran out of rpm before the tranny shifted into second gear but my '85 was the worst. I had a friend who put siamed runners on his '85 and it cured that prob. I've also heard extra fuel pressure fixes that prob too but you'll need an adjustable fuel pressure regulator and a gauge for accurate measurments.
I tried adjusting the TV cable and I was able to make an improvement in the 1-2 shift but then the 3-4 shift was screwed up. Best to adjust that like the factory specifies and search for remedies elsewhere.
BIG JIM
[Modified by BIG JIM 54, 6:00 PM 10/23/2002]
10-23-2002, 01:59 PM
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Re: 1985 Transmission Question (BIG JIM 54)
never buy a hypertech chip, ever its a waste of money, unless somebody will sell you one for $20
If you believe something is actually wrong with it, then take it to a tranny shop and have them look at it. Dont go messing with chips.
If you believe something is actually wrong with it, then take it to a tranny shop and have them look at it. Dont go messing with chips.
