How to adjust shift points on 85
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Joined: Jun 2001
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From: Elverson PA
How to adjust shift points on 85
I was just reading in my old TPIS "Insider Hints" about how they gained .3 in the quarter by adusting their shift points in their auto car from 4500 rpm to 4200 rpm. I guess that would be w/ the TV cable? It says in the book that there is some "tab on injector" that you move forward to lower the shift point. I don't know about any injectors on the tranny or anything...
My car , an 85, shifts at a really high rpm and it just doesn't pull very hard up there. Also the valves make a lot of noise between shifts. I was wondering if maybe my tv cable is stretched. Maybe my springs are getting weak. Anyway, I really want to get into the 12's this spring, so if you have any advice please share.
On a side note, I just bought the March underdrive pulleys. I'll have to post some results when my local track opens.
My car , an 85, shifts at a really high rpm and it just doesn't pull very hard up there. Also the valves make a lot of noise between shifts. I was wondering if maybe my tv cable is stretched. Maybe my springs are getting weak. Anyway, I really want to get into the 12's this spring, so if you have any advice please share.
On a side note, I just bought the March underdrive pulleys. I'll have to post some results when my local track opens.
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Originally Posted by black85
I was just reading in my old TPIS "Insider Hints" about how they gained .3 in the quarter by adusting their shift points in their auto car from 4500 rpm to 4200 rpm. I guess that would be w/ the TV cable? It says in the book that there is some "tab on injector" that you move forward to lower the shift point. I don't know about any injectors on the tranny or anything...
My car , an 85, shifts at a really high rpm and it just doesn't pull very hard up there. Also the valves make a lot of noise between shifts. I was wondering if maybe my tv cable is stretched. Maybe my springs are getting weak. Anyway, I really want to get into the 12's this spring, so if you have any advice please share.
On a side note, I just bought the March underdrive pulleys. I'll have to post some results when my local track opens.
My car , an 85, shifts at a really high rpm and it just doesn't pull very hard up there. Also the valves make a lot of noise between shifts. I was wondering if maybe my tv cable is stretched. Maybe my springs are getting weak. Anyway, I really want to get into the 12's this spring, so if you have any advice please share.
On a side note, I just bought the March underdrive pulleys. I'll have to post some results when my local track opens.
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Joined: Jun 2001
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From: Elverson PA
Does anyone know what TPIS is talking about? Here is the quote:
"With the motor off, have somebody depress and hold the throttle to the floor. On the left-front of the injector, there is a re-adjust tab. Depress it to release the cable housing. Then pull the housing back until the cable is just tight. Now, by moving the housing back and forth one click at a time, you can move the shift point up or down to achieve the desired results. One click forward will cause it to shift sooner."
I assume they were talking about the tv cable, but wtf? Why is this called an injector? Maybe if I had my car in front of me it would be more obvious, but it is stored in a garage down the road. Thanks!
"With the motor off, have somebody depress and hold the throttle to the floor. On the left-front of the injector, there is a re-adjust tab. Depress it to release the cable housing. Then pull the housing back until the cable is just tight. Now, by moving the housing back and forth one click at a time, you can move the shift point up or down to achieve the desired results. One click forward will cause it to shift sooner."
I assume they were talking about the tv cable, but wtf? Why is this called an injector? Maybe if I had my car in front of me it would be more obvious, but it is stored in a garage down the road. Thanks!
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Originally Posted by black85
Does anyone know what TPIS is talking about? Here is the quote:
"With the motor off, have somebody depress and hold the throttle to the floor. On the left-front of the injector, there is a re-adjust tab. Depress it to release the cable housing. Then pull the housing back until the cable is just tight. Now, by moving the housing back and forth one click at a time, you can move the shift point up or down to achieve the desired results. One click forward will cause it to shift sooner."
I assume they were talking about the tv cable, but wtf? Why is this called an injector? Maybe if I had my car in front of me it would be more obvious, but it is stored in a garage down the road. Thanks!
"With the motor off, have somebody depress and hold the throttle to the floor. On the left-front of the injector, there is a re-adjust tab. Depress it to release the cable housing. Then pull the housing back until the cable is just tight. Now, by moving the housing back and forth one click at a time, you can move the shift point up or down to achieve the desired results. One click forward will cause it to shift sooner."
I assume they were talking about the tv cable, but wtf? Why is this called an injector? Maybe if I had my car in front of me it would be more obvious, but it is stored in a garage down the road. Thanks!
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From: The Top of Utah
What they are talking about is messing with the TV cable. I think they are just giving a poor description of the location of the adjustment point with the word "injector". In any case, it's bad advice, as Pete K pointed out. The TV cable adjustment doesn't have a great influence over the shift points, and if it isn't adjusted properly, where it's supposed to be, you're flirting with a transmission failure. Leave the TV cable alone, or verify it is properly adjusted. Even if the governor gear isn't bad, the shift points are properly altered by changing the weights and springs of the governor.
RACE ON!!!
RACE ON!!!
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From: Elverson PA
Thanks everyone. Maybe I should look into the governor gear and weights some day. Trans work might be a little advanced for me. For now, I guess it runs fine. It does seem to keep on reving after the power is gone. I guess this is just typical of an L98.
Dave
Dave
Last edited by black85; Feb 27, 2005 at 11:37 AM.
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From: Elverson PA
Mine does shift at 4500-4700. In between shifts it seems like the engine just does a little over rev. It is like the trans shifts, but when the clutchs disengage the engine continues to rev higher for a second until the next gear catchs. This is when I hear what sounds like valve float or pinging. Also, the car makes much more power down in the lower rpm's so if I could get it to shift sooner I could avoid that over-rev and get back into the powerband sooner. I don't have my dyno chart here (could check tomorrow cuz it is a work), but I think it really starts loosing power up at those higher rpms.
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The symptoms you describe sound more like "shift flare up" This is common with a non vette trans. The vette uses a larger servo for a more firm apply on the band. Many vettes have had blazer or camaro trannies retro fitted into them over the years. If this is the case a 30 dollar servo would make a big difference. If this is not the case and you do have a vette servo in your vette tranny, symptoms are typical of a band and/or clutchpacks with clearances on the high side due to wear or other reasons. "I" would id the trans first.
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From: Elverson PA
Yea, you are probably right, I am over 130,000 miles so maybe I need a rebuild. Also, maybe I was just low on fluid. I have been dealing with a leaky tranny pan, and found I was low last time at the track. I don't think this trans has ever been touched (I know previous owner well) other than using Amsoil fluid for the last three years.
I'm going to have to make sure this thing has enough trans fluid in it. Hopefully it has stopped leaking; I retorqued the pan last time I had it out. It shifts really weird when it is only a quart low. It has leaked ever since the tranny flush, but the bolts weren't torqued correctly at first. It used to have RTV around the pan gasket, but when I reinstalled it I did not use the RTV, just a gasket. Maybe I just need a new gasket since the old leaked for so long. Any thoughts?
I'm going to have to make sure this thing has enough trans fluid in it. Hopefully it has stopped leaking; I retorqued the pan last time I had it out. It shifts really weird when it is only a quart low. It has leaked ever since the tranny flush, but the bolts weren't torqued correctly at first. It used to have RTV around the pan gasket, but when I reinstalled it I did not use the RTV, just a gasket. Maybe I just need a new gasket since the old leaked for so long. Any thoughts?
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If you do change the trans pan do not use rtv. There is a small hole right next to the pan gasket that could get plugged. This is the servo dump port. If you must coat the gasket w/ something, use a thin coat of vaseline only. Most people are not aware of this small hole until it is pointed out to them. Plugging this hole is certain death for the box. I prefer a paper (fiber) gasket over the cork.
