Hey guys I'm wanting to totally simplify my '84 Trans Am. I've taken off all the emmisions and air pump. Do I need to bypass or eliminate the computer? I'm changing the carb, intake, cam, and replacing the exhaust with headers and muffler, no cat. Any suggestions?

 

You have a vacuum advance HEI on the car, right? Do you know if you have a lock up converter or not? If you have an electric advance dist and a lock up converter then you still need the computer. My advice is leave it because it's not hurting anything.

 

I do have a lock out converterand the stock hei that I was planning to change out. I was concerned about the computer not getting any readings from the sensors. Thanks for the replies

 

An older GM HEI will work in place of the stock computer controlled HEI. The lock up function on the torque converter can be taken away from the computer. B&M sells a ratchetting shifter made to fit right in the stock third gen center console. They give directions for replacing the switch with a relay, but I am 99% sure you can replace it with a switch.
For driving around town, you don't need the torque converter to lock up at all. So keep it off. Turn it on for extended trips on the highway. Should not hurt the torque converter if you forget to turn it back off when you get off the highway, but for that, I'm going to use a nice brightly lit switch, for the "oh yeah" effect.

 

:hail: You guys are great! I've got the tranny out being gone through what if I put a stall converter on before putting it back in?

 

The shifter itself has nothing to do with the lockup function. Besides, it would be a pain in the *** to have to flip a switch every time you want to lock up the converter. There is a kit that you can install in the valvebody that uses a pressure switch to determine when it needs to lock up the TCC that totally eliminates the need to have the computer in the car. That's the "right" way to do it.

 

A toggle switch works just fine and is a lot cheaper at about $3 vs. $80 for a kit...just mount it right behind the shifter on the console and it will be right there when you need it...I had to do this to mine because the computer wouldn't lock my converter up at all...works great

 

Again thanks. Is there a thread that would describe the two procedcures? What is the kit called? Can it be done with the transmission in the car? Again thanks, would replacing the lock up with a stall eliminate the need for the computer. I probably need to post this question on another thread.

 

I know this is probubly a stupid question, but I was also taking the comp out of my '86 Z. And was wandering if taking out the comp, would eliminate the use of the A/C. Is this so?

:lala:

 

AfootVoyager How do you wire the switch in?

 

you need to run a positive lead from any source...you probably ought to put a fuse on it...make sure that your source is always on or at least comes on with the ignition...run it to the toggle switch...take the switched lead from the toggle switch and run it to the plug on the tranny..sorry but i dont remember which plug is which...just try it till it locks up when u flip the switch...if i remember right one is for the lockup, one for the temp sensor to computer....i dont remember the other two...it might take some trial and error but not long...just make sure you have a good positive source in the first place...you will definently know when you get the right one.....hope this helps...

 

I don't recommend "finding wires by trial and error by running 12v through them until something works".

 

Why not use a multimeter to find the right 12V source?

 

Actually, the shifter does apparently have something to do with the lock up function of the torque converter, according to B&M.
I bought the B&M ratchetting shifter for my IROC, but have not installed it yet. I was a bit puzzled by their instructions to wire it up to still use the lock up function using a Radio Shack relay.
It looks like there are about 4 wires that go through the shifter harness. And they give you the choice to run it like stock, by using that relay, or run it without a lock up function, by eliminating the relay. I found that a little bit confusing, so I'll have to sit down and study it further.

Having your torque converter locked in around town driving shouldn't hurt anything, if it was actuated and forgotten to turn off. However, the only time I would want the lock up function is out on a highway cruise. All other times, it wouldn't bother me to have more torque converter slippage around town.

But like I said, I have to study B&M's documentation more before I actually install that shifter. It's apparently not a straight forward swap.

 

Look...I am not talking about just running random sources of 12v through out the car to just anything...there is a temp switch output...and something i just can't seem to think of...and the input for the lockup...if everything was operating correctly then when the temp was high enough and the switch tripped it would send a signal to the computer which would in turn check all the other variables...ie. speed, engine controls...and then send a signal to the lockup solenoid to do its thing....all of this becomes irrelevent when you decide to bypass the computer....none of the sensors and/or switches inside the transmission besides the lockup solenoid will be necessary if you decide to bypass the computer....so what will you lose???...just for kicks tho tomorrow i will climb under my car and look at the plug to let you know how mine is connected...you know...the one i figured out by running random sources of 12v everywhere...

 

Hey Rockin Iroc, What style shifter is that from b&m? If it has the fuctions you're talking about it may work out great, I could use a new shifter. Thanks for bein' here.

 

My pleasure.
It's a B&M Console Megashifter for a 1982-1992 Camaro/Firebird, part number BMM80692, price $151.95.
Summit and Jegs sells it.
Summit: (800)230-3030.

 

TCI makes a lock up kit for your 700 r4 i have one in my car.

 

Computers in cars .......what ever happened to the good ole days??

 

They became the good ol' days, like good new days typically do.

The B&M shifter doesn't effect actual TCC function in normal driving. What actually happens when you hook up the shifter according to the instructions without the relay, is that the computer is no longer informed whether or not the car is in Park/Neutral. Of course, the TCC isn't going to lockup if it thinks it's in Park/Neutral all the time (which is what happens if you don't add the relay), but that has absolutely nothing to do with the TCC locking up or not when the ECM is removed. The fact is, if you remove the ECM, there is nothing to tell the TCC to lockup and adding an aftermarket shifter isn't going to take the place of the ECM in doing that. A person either has to reprogram the transmission with the aforementioned kit so that it knows by itself when to lockup under broader conditions than the computer would have determined, or they have to wire up a switch to lock it up manually. And locking it up manually is a pain in the *** if you care about the longevity of the torque converter clutch. The actual clutch is a band only about an inch wide. If you put a lot of driveline stress on it, ei, accelerating, decelerating, it's not gonna last very long. Not to mention that if the transmission is slipping more often, that builds heat, and heat is a transmission's worst enemy. And lastly and most importantly, transmission fluid is only routed through the cooler when the TCC is locked. So if you don't really care how long the transmission will last, then that's all your business. I just have this point of view because I've had my baby for 13 years, and plan to go the distance with it, and longevity is the name of the game.

 

By the way, here's another side effect of installing that shifter without the additional relay that lets the computer know when it's in Park/Neutral. The computer doesn't know when it's been placed into gear (reverse or drive). Normally, when the computer notices it's been placed into gear, it'll kick up the idle a bit to compensate for the drop in RPMs that normally accompany an automatic transmission going into gear. Without that information, when your car is placed into gear, the RPMs will drop almost to the point of stalling before the idle comes back up because it still thinks it's in park.

 

Hey Jza, What do you think the effect would be if I used the computer do monitor and run the transmission and distributor but eliminated the emmissions and changed intake and carb?

 

Relax. I'm learning about these cars too. I've had a third gen F-body for less than a year, and I'm still fixing all the problems from the previous owner.

I'm not running a stock torque converter. I spent a lot of money and had a strong custom lock up torque converter built for a 2200 rpm stall. I'm not worried about a relatively weak stock converter fragging, since that weak link's been removed.

Torque converter slippage does produce extra heat, and if you have a great deal of slippage designed into a high stall torque converter, then yes, you need a very good transmission cooler. Usually the aftermarket variety on the front of your radiator or something. By itself, having a higher than stock stall in your converter doesn't kill an automatic transmission. If you keep it down below 2400 or so, you can use the stock tranny cooler in the radiator without much problem. If you're concerned, you can either add another cooler, and/or increase the transmission pan volume to hold more fluid.

To me, having a transmission ONLY route its fluid through the cooler when the TC is in lock up simply doesn't sound right. Forgive me if I don't believe you but I don't. I will check on that. I've never heard of a transmission that does that.

Let me explain. The two notches on the sleeve of the torque converter's center tube that slides into the transmission and engages with two teeth is actually engaging the transmission fluid pump. Now if you run a transmission without fluid pumping for even a slight distance, you won't have a transmission any more. This is the big danger if you don't install a torque converter right.

I'm not condoning manually switching on or off the lock up function, I'm just exploring that option and trying to find out the effects.

And like I said, I'm still learning about these cars.
I come with other experience...see below.

 

JZA, thought about what you said and come to think of it. Ever since i started messing with computers, i can't remember ever having any good ol days related to them. Just major headaches and setting around for hours trying to figure what works with what to make it run right.

 

the neutral safety switch has nothing to do with the locking up of the TCC. find the relay for the TCC and work with that. I would get the kit for $80. the whole idea is to make it simple right? it will be hard to tell how much you've gained because of you mods,I'm leaving my computer in.

 

Rockin-Iroc: No problem. I'm not jumping on you or anybody, I'm just trying to keep things focused. I understand that you're not running a stock torque converter, but I'm assuming that the originator of the post is. What I stated is fact, and that's okay that you don't believe me about the fluid being routed to the cooler only under lockup. I agree with you that it doesn't sound right, and that it's a crap design. And I know that you're not worried about heat-related problems, but we weren't discussing your car (***, that last sounds harsh; I want you to know that I don't mean it in an ******* way). Anyway, sorry if I came across like "I know more than you". Mentioning my car's age was an expression of how long I plan this car to last, not how long I've been playing with it in one form or another.

 

Hey, no worries Jza.

I just found out m MAF sensor burned out due to a stuck relay.
Oh great. Now I get to buy a $500 Bosch MAF, when all it needed originally was a $30 relay. Why the frick doesn't a stuck relay trigger a computer code?

I've got a feeling this computerized car is going to be a real adventure. I've got to admit though, this 350 sure likes the TPI. It's much faster than when it had a Holley on it in my 68 Corvette. And with the carb, I was beating the new LS1 F-bodies by half a second and 7 mph.

I know it's off topic, but if you know anyplace that sells rebuilt MAF's please let me know.

 

The TCI kit uses a vacum line to kick it on or off.In the jegs catalog its part #890-376600.