Marcus18 Posted September 12, 2003 Report Share Posted September 12, 2003 I know before the tg160 chip that overdrive wouldn't kick in until you let off or below 3000 rpm. but I haven't really tried since I put it in. The other day I'm going down the highway with the pedal to the floor with this saleen and I think it shifted or something because my rpm droped real low. Then yesterday I floored it again on a back road and it shifted into overdrive at 4500rpm/90mph and went to 2500-3000rpm. is this normal? I changed the vac modulator a few weeks ago. yesterday I found the metal line that goes from the pleneum to the vac modulator halfway out of the rubber where it attaches at the pleneum. it still shifted thatway afterwards though any thoughts? Marcus Quote Link to comment Share on other sites More sharing options...
Jeff M Posted September 12, 2003 Report Share Posted September 12, 2003 Thanks for the detailed description/stuff you have done as well. First some background on the chip, GM or mine as this stuff is the same. Overdrive to me is just 4th gear, we have a 4 speed auto, that might make it simpler to talk this, and only a few early 1989 TGPs would allow 4th gear at WOT, all the rest will not allow this, AND this 4th gear at WOT is not controlled by the chip. There is also the torque converter that comes into play, and it is controlled only by the ECM. Once the engine is warmed to a certain coolant temp, the TC will be allowed to lock then based on TPS and MAP. BUT there is one setting in the chip that locks the TC no matter what and that is high mph, I would say the mph you were talking about when you noticed the rpms drop, off hand but I can dig the actually value out of my chip doc, somewhere in the high 80 mph range. Also the TC can be allowed to lock in 3rd as well as 4th gear. Aside from those norms, a tranny that is shifting into 4th gear at WOT is one that is getting some age, and the worst age for it is high-speed runs. High-Speed runs in 4th gear are too much for 4th gear, especially since stock 4th gear is comprised of one clutch and one steel (compared to several of each in other gears). When this one clutch and steel are asked to push a car through air at high-speeds, it starts to slip, clutches burn, steels burn and warp and when warped enough, will start to lock/go into gear when 4th is not supposed to! A few that have done high-speeds found this “locked into 4th gear†when they came off the highway and the car would not move/tranny locked/stuck, no go. So just some background info to hopefully help you out, and others as well! Jeff M Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted September 12, 2003 Author Report Share Posted September 12, 2003 I guess I'll keep it out of 4th when driving crazy. I guess it could be getting old with 143000 :? on a completly different subject, do you think it would be safe to run 89 octane once the temp drops to 70's and below? gas prices are killing me. marcus Quote Link to comment Share on other sites More sharing options...
1badtgp Posted September 12, 2003 Report Share Posted September 12, 2003 That sounds like what I did to my last trans. I was doing about 90 and let off the gas a bit and forgot to take it out of OD. Car went into 4th, and cruised just fine. I stopped, and the car will not move. And it wont rev over 2400 rpm. It's like it's locked in gear even in park. Does that sound about right? Also, we have a shop car 89 GP SE that has done the same thing. Is there a way to get it to unlock without taking it all apart? Quote Link to comment Share on other sites More sharing options...
PaPaPooh Posted September 12, 2003 Report Share Posted September 12, 2003 sound like a stuck valve in the valve body to me EDIT: guess i should quote this That sounds like what I did to my last trans. I was doing about 90 and let off the gas a bit and forgot to take it out of OD. Car went into 4th, and cruised just fine. I stopped, and the car will not move. And it wont rev over 2400 rpm. It's like it's locked in gear even in park. Does that sound about right? Also, we have a shop car 89 GP SE that has done the same thing. Is there a way to get it to unlock without taking it all apart? Quote Link to comment Share on other sites More sharing options...
Jeff M Posted September 12, 2003 Report Share Posted September 12, 2003 At a stop, engine only revs/car does not move is 4th gear locked/burnt and cannot release, that is why you can be cruising ok on the highway but when you come to a stop it will not move, like staring out in a manual tranny in 4th or 5th gear, just the TC keeps you from stalling the engine. So it never released 4th since 4th is now seized together. I have seen my share of these here, bad looking pieces that can only be replaced with an overhaul. As for 89 octane, long as you don’t hammer the boost too much in hot weather or long WOT runs in warm weather, and when you are boosting and if you are knocking you will notice this by the boost coming down on your gauge or dash boost indicator, as the chip is backing the boost down, not just timing retard/knock retard, slick chips but I can’t take that credit, they all have these dual save-your-ass features. When this boost drop happens, back off the gas pedal. Same dropping boost thing will happen with some higher mileage TGPs that have the original fuel pump/fuel filter and too many miles, just how much is too many miles, no way to state that with so many variables, but know the chip has enough leeway to cover the major share of TGPs, no chip anyone can do will overcome worn out parts. And before I forget, threaded wastegate rods too tight, and those will manual boost controllers are on thier own as the ECM no long has that control! Jeff M Jeff M Quote Link to comment Share on other sites More sharing options...
1badtgp Posted September 12, 2003 Report Share Posted September 12, 2003 $#%@#^%$^$^#$^ Transmissions!!!! NUMBER FRIGGIN 7!!! BAAAAA!!!! Anyone know where I can find the 5-speed. None of the j-yards here have them. Unless it will work from a Cav Z-24. BTW, thank you for the insight Jeff. I would wait for the trans kit you had talked about, but I need to cure this things ills. Quote Link to comment Share on other sites More sharing options...
Marcus18 Posted September 12, 2003 Author Report Share Posted September 12, 2003 well I haven't been driving in overdrive unless I'm up to speed. everything is okay. I just drive in 3rd until I'm up to speed. wow I haven't driven in just 3rd sense the first month I had it. not having to downshift makes things go faster. I smoked a little rsx today I burned off the line and he chirped his tire but I was gone by then. love the car!!! I'm not going to run 89 until it gets colder here, not going to take any risks with that. marcus Quote Link to comment Share on other sites More sharing options...
TurboGTU Posted September 13, 2003 Report Share Posted September 13, 2003 Why only one clutch in 4th is a mystery...and so freaking dumb. Well they have to make money for the trans shops right... That cavi 5spd should work...what you need from a w-body 5spd is the passenger side axle extension, complete clutch pedal assy, just the brake pedal from the 5spd(narrow vs long from auto) , shifting cables, shifter and all parts, and mounts I think. If a j/y just pulled the trans but left thise behind then just grab that and buy the cavi trans and it should work...with the fly wheel too ofcourse. A new cluch kit is always a plus. Though the TGP engine will most likely smoke the stock style clutch. TGPilot and Malabu know what is needed. But if your inclined of doing it ...or another rebuild then get a 3t40 from the w-body , rebuild it with redline performance clutches , steel parts and be done with it. No one cluch wonders there,,,,or long down time to worry about. Just my two cents. Quote Link to comment Share on other sites More sharing options...
god910 Posted September 13, 2003 Report Share Posted September 13, 2003 (showing J-Body ignorance) If a Z24 only came w/ a 2.8/3.1 then just call me an idiot and disregard. IF the car has a 4 cyl. than the tranny is not a getrag and will not work. I went through this a few months ago. Quote Link to comment Share on other sites More sharing options...
Chris A Posted September 13, 2003 Report Share Posted September 13, 2003 $#%@#^%$^$^#$^ Transmissions!!!! NUMBER FRIGGIN 7!!! BAAAAA!!!! Anyone know where I can find the 5-speed. None of the j-yards here have them. Unless it will work from a Cav Z-24. BTW, thank you for the insight Jeff. I would wait for the trans kit you had talked about, but I need to cure this things ills. Lets back up a second here. If you have had 7 trans failures lately , then something else has to be wrong. Heat kills. Have you replaced your trans cooler and added a second one. You would be surprised at the amount of heat the tranny generates and I strongly recommend a second trans cooler. The one in the fender is a nice OE addition, but I don't think its sufficient. At the very leats replace the OE one with a similar one (they are out there) since you can't be assured its not clogged with clutch parts. and flush the cooler lines. Have all 7 of your failures been the same? Chris Quote Link to comment Share on other sites More sharing options...
PaPaPooh Posted September 13, 2003 Report Share Posted September 13, 2003 IIRC OD is a band that uses the first reverse cluster with 4 or 5 clutch packs in it. i guess you can call the band a clutch if you want not sure tho its been a while since i tore one apart (anyone correct me if im wrong?) Quote Link to comment Share on other sites More sharing options...
Chris A Posted September 13, 2003 Report Share Posted September 13, 2003 Not in this tranny. I'm by no means an expert, but OD is a dedicated clutch on the far left side of the tranny, near the driver side output. Quote Link to comment Share on other sites More sharing options...
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