Guest tony78_280z Posted January 10, 2005 Share Posted January 10, 2005 I have figured out that I have a THM350, not a 700r4. I can't find any good information on this non-overdrive tranny type. Does it have a torc converter lock out that I need to have wired up? If so where? It has two electrical plugs into the tranny. One Four wire plug that plugs into the driver's side, and one two wire plug that plugs into the passenger side. Which of these do I need to fuss with? Of these multiple wires on these two plugs, which wire do I need to jump the juice to? Does one need to be grounded? Or am I wasting my time because this torc converter locks up on it's own via oil pressure? Thanks Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 10, 2005 Share Posted January 10, 2005 I think what you have there is a THM350C, which is a lock up version of the 350, came in many 80's models rwd cars in the effort to improve mpg's prior to the overdrives becoming mainstream. My '84 Monte SS had one in it. The plugs on the side are for shift input to the computer and the other is for lock up, you'll need the plug in connectors If you don't use the plug in's then the trans will work but not have lockup in the converter. B&M makes a lockup switch so you can have lockup. Your call, there, IMHO I'd use a regular thm350, or probably better a 700r4, 200r4, 4l60e or even better 4l80e so you'd have overdrive. I run a powerglide in my boys z, but it's really race only with minor forays to whoop street bootie. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted January 10, 2005 Share Posted January 10, 2005 "I think what you have there is a THM350C" How can I verify this so that I know for sure. The tranny pan matches the description for the THM350 model, But I do not know if I got the THM350 or the THM350C. "The plugs on the side are for shift input to the computer and the other is for lock up, you'll need the plug in connectors" Can you tell me which is which. Drivers side plug or passenger side plug? Do you know which wires I need to run hot and which I need to ground? "B&M makes a lockup switch so you can have lockup" I plan to run a toggle switch for now.. I just wanna know what wires to put the switch into. "IMHO I'd use a regular thm350, or probably better a 700r4, 200r4, 4l60e or even better 4l80e so you'd have overdrive." Some day I may do this, or I'll get a 5 speed manual. But for now I would like to have it working properly. Thanks for the reply Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 10, 2005 Share Posted January 10, 2005 I can about guarantee you it's a 350c. One of the plugs should have two pins and the other should be 4 pins and I think they are even different colors (white and black). The two pin, if my memory serves me correctly, is for the lock up, one is for ground, the other is 12v juice when you want it to lock up. If you forget to untoggle it, it'll die when you stop the car, which will remind you to untoggle it and restart. The trans takes the same components as the 350 with, I believe minor differences in gaskets on the valve body for the lockup, maybe the input shaft is different, It's been too long since I rebuilt one, so I'm alittle fuzzy. Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted January 10, 2005 Share Posted January 10, 2005 Yes, one plug has 4 pins, and the other has 2 pins. In my wiring harness one pin of the two pin goes accross the tranny and into the 4 pin. The other pin in that plug goes off and is cut. So one of these could be the power and gound for the lock up? Do I run the chance of burning something up if I wire this backwards? Man I wish I could find some good schematics on the net somewhere. =( Thanks for the info Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted January 11, 2005 Share Posted January 11, 2005 So this evening I spent some time with my Z. I jumped some juice to the passenger side (2 pin) on the tranny. It is a black rubber plug with two electric socket looking plugs. I grounded out the other and fired it up and threw it in gear. It didn't try to die or stumble and lurch (like a manual would if left in gear) So I switched the plugs around (+ became - and vice versa) and fired it up. Nothing. So does this torc lock up only work if the car is moving? (I'm also having headlight issues so I didn't get it out of the garage) Or do I have the wrong wires? Or should I just give up and roll it out into the pond? Man this has realy got me stumped. I can't find any real helpful info on the net. I've wasted money on Haynes books before (Holley Carb, Autobody & Paint, 240 260 & 280Z in which my car is only mentioned in the appendix) that didn't give me enough specific info for my money, so I don't trust them. I'm at a loss here. I'm all depressed, and feeling low... My sex drive is down. Even beer doesn't cheer me up... Nothing tears me up like my baby in the garage rusting away. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted January 11, 2005 Share Posted January 11, 2005 Do you have the plug that should connect to the tranny? or are there just 4 wires sticking out of the tranny? What color are the wires? Guy Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted January 11, 2005 Share Posted January 11, 2005 Yes I have the plugs... I don't recall the colors... I was just lookin at them last night... They aren't properly red and black, and that hardly matters as the plugs wires are not hanging out of the tranny, and the plug can go in either way. Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 11, 2005 Share Posted January 11, 2005 Crap, I honestly can't tell you, cause I don't have one handy to take the pan off and see. I'd call a trans shop or B&M. Honestly dude, I'd have to be there, but again, if my memory serves me, and with what happened yesterday, that's a big if, there is a solenoid on the valve body that makes it work, ie. puts fluid to engage the clutch in the converter. If you trace that wire to the right plug, that should be it. Yes the engine had to run to work otherwise you won't have fluid pressure in the trans, but I'm trying to remember if it was connected to the other wires something about governor pressure to keep it from stalling the car as a stop. I just can't recall, been too long. Crap, I've got to find a carb for the qjet question guy and take some pic's of the z for another guy here on this forum, I"m a slacker. Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted January 11, 2005 Share Posted January 11, 2005 The torque converter should work like a normal one from 1 through 3rd gear. It will only lock up in 4th ( but I think in your case 3rd gear) Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted January 11, 2005 Share Posted January 11, 2005 You sure? I heard people say that if they forget to disengage the toggle switch while coming to a stop it'll make it stumble lurch and wanna die like a manual left in gear. SO are you saying I gotta get it up into 3rd then lock it in and it'll stay in? You mean I had it wired right last night I just couldn't tell cause I didn't get it into 3rd? Will it still downshift as I slow? Thanks for the responses Oh and Mike KZ... Nice friggin car! I love the body on Page 1 (http://members.tripod.com/~SnowSurfer/zcar1.html) It's almost as if you read my mind on the body style. Hood, rear end, and fenders. I'm gonna have more of a ZG type nose. What did you use to make that rear end? Is that out of a vet? And the head lights. Very interesting. I'm gonna steal a couple of idears for when I do the fiberglassing part of this project this summer. (If I ever get the car running correctly =( Quote Link to comment Share on other sites More sharing options...
BrandonsZ Posted January 11, 2005 Share Posted January 11, 2005 try looking up a manual for the 350c, it might have something to do with the other 4 wires too, that power connector may just be power, for the solenoid, but there may be a relay that needs singnal power as well. Skip the beer and go straight to the rum, after 4-6 shots, you should forget you even have a Z.* *warning effects are limited and hangovers are severe. And for god's sake stay away from goldshlager and pepermint schnaps. Otherwise who needs the lockup anyway, you planning a long trip? Need that extra 5% gas mileage on the freeway? Quote Link to comment Share on other sites More sharing options...
Mike kZ Posted January 11, 2005 Share Posted January 11, 2005 You sure? I heard people say that if they forget to disengage the toggle switch while coming to a stop it'll make it stumble lurch and wanna die like a manual left in gear. SO are you saying I gotta get it up into 3rd then lock it in and it'll stay in? You mean I had it wired right last night I just couldn't tell cause I didn't get it into 3rd? Will it still downshift as I slow? Thanks for the responses Oh and Mike KZ... Nice friggin car! I love the body on Page 1 (http://members.tripod.com/~SnowSurfer/zcar1.html) It's almost as if you read my mind on the body style. Hood' date=' rear end, and fenders. I'm gonna have more of a ZG type nose. What did you use to make that rear end? Is that out of a vet? And the head lights. Very interesting. I'm gonna steal a couple of idears for when I do the fiberglassing part of this project this summer. (If I ever get the car running correctly =([/quote'] --- That is right, it will stall when you come to a stop if you forget to toggle the switch. The lockup is for overdrive only, not for the rest of the gears. The car you refer to is my friend Lee's car, email him if you have questions. Quote Link to comment Share on other sites More sharing options...
flibuoy Posted January 12, 2005 Share Posted January 12, 2005 One of the FEW satisfactory dealings I have had with vendors was with Darrell Young, Northbridge CA...sorry do not have site or Phone any longer. In my case I was using a 1989 Z-28 700-R4 in my first Hybrid Z and he fixed me up with a easily installed setup that locked converter automatically, immediately, in 4th only AND it unlocked automatically too...simple and several years ago was under $120. He could have sold me a shift kit too but he instead advised the Z-28 would shift plenty hard in light body...he was right! I suggest anyone interested in the 350, 400 or 700 call him to see if he can help, he sure knew what I needed. John Quote Link to comment Share on other sites More sharing options...
80LS1T Posted January 12, 2005 Share Posted January 12, 2005 I'll try to find some info on SHOPKEY tomorrow at work. Anyone know what kind of car this 350C tranny came in? Was it stock in your 84' Monte SS, Dr Hunt? I will try looking it up under that car. Guy Quote Link to comment Share on other sites More sharing options...
rick phillips Posted January 13, 2005 Share Posted January 13, 2005 tony 78 i used a 350c trans for two years in my 77 280 w/350. the 350c was actually on the trans case for iding it. i talked with the guys at bow-tie over drives who advised me the wiring diagram on the web site would work for me its the four wire plugand it does have to be grounded. but performance was minimal for me. i have recently changed to a 700r4 and driving the z is fun again. hope this helps are gives you another avenue to persue. rick Quote Link to comment Share on other sites More sharing options...
Guest tony78_280z Posted January 13, 2005 Share Posted January 13, 2005 Thanks for all the good info! From what bowtie overdrives says... A 700r4 uses the 4 pin plug on the drivers side of the tranny. While looking at this plug with the clip at the top, bowtie says that the top left pin is the power. They don't mention the ground. Can you please tell me which wire should be the ground? Or should I just ground all the rest. I'm sure I wont get much economy gain from setting this up properly, but every little bit help, and yes, I do a bit of highway driving. If I should go with a 700r4 then I can keep this set up. I'd prefer to have a manual 5 speed, but seeing as how these are rather rare at the junkyard, and very expensive new, I may need to settle for a 700r4 for awhile. Thanks again, after the rain stops I'll grab the wire strippers and the sodder gun. ps. On the plus side I spent some time setting up some realy cool toggle switches on my Old ECU cover. They look sweet. They are the kind where the light glows red when power is on. I got my fog lights, back up lights and hopefully soon my Torc Lock up switches. I ran power from fuse box after the AC fuse. So they only have power when the car is on, and they are fused. (I don't got the AC anyhow) Doing this minor chore and having success cheered me up a little. =) Quote Link to comment Share on other sites More sharing options...
rick phillips Posted January 15, 2005 Share Posted January 15, 2005 tony280 thats the correct wire for the power, but i can't remember which is the ground. i am at work and dont have my notes. i think there were only two wires left i ran them inside and grounded one and then the other and found the right wire. i put it on a toggle switch and ran it through the low fuel light on the dash. it didn't work at all before ,but now it reminds me when the overdrive is engaged. the converter in the 350c droppedthe rpms by a couple hundred. rick Quote Link to comment Share on other sites More sharing options...
dr_hunt Posted January 15, 2005 Share Posted January 15, 2005 Guy, I know that the turbo 350c came in the Caprice and Monte carlo SS, I had both a 79 caprice and a 84 Monte SS. I didn't buy a new vehicle until I was 35 years old. The caprice was falling apart and the Monte SS got stolen and ended up in Mexico. You'll get it figured, sorry I couldn't remember everything. Quote Link to comment Share on other sites More sharing options...
80LS1T Posted January 15, 2005 Share Posted January 15, 2005 Sorry I havent posted any info yet.......I keep forgeting to look it up. I'll try my best to remember on Monday. Guy Quote Link to comment Share on other sites More sharing options...
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