J0hn_J0hn08

iTrader: (2)

So ive been reading about swapping out the quadrajet for a holley

seems like ill need a carb, intake, and older fashioned hei dizzy.

Now i also read that ill need a lock up switch or ill burn clutch packs in the transmission.
How exactly does that work? and is it a hard task to do?

could i get away with running a tranny cooler instead?

I never understood the purpose of a converter lock up switch

Apeiron

The converter switch controls locking of the torque converter clutch.

J0hn_J0hn08

iTrader: (2)

thanks for the reply apeiron. What is the purpose of locking it though?

And would a tranny cooler eliminate the need for one?

z28romance

The purpose of locking the converter is to put the car in to over drive. in other words, over drive is a converter lock up.

J0hn_J0hn08

iTrader: (2)

thanks for clearing that up z28.

So technically if i drove the car in drive only and not overdrive, i wouldnt need to worry about burning up any clutches without the switch correct?

Apeiron

No. Overdrive is a 4th gear which drives the output shaft of the tranmission slower than the input shaft. Nothing to do with the torque converter.

The torque converter has a clutch that will lock the converter input and output to eliminate slippage. Slippage produces heat, and slippage is highest while cruising at low engine speeds (such as in overdrive), which is also when fluid flow through the converter is lowest.

J0hn_J0hn08

iTrader: (2)

Apeiron, so do i really need to spend the 200 bucks on a kit to rig up a switch and lock up the converter when converting to a regular non computer controlled carburetor?

Or can i just get a tranny cooler instead and not have to worry about it?

Im really just trying to find an alternative to having to rig up a switch.

thewizard

iTrader: (43)

^I think Apeiron meant to type faster as opposed to slower.

To add, the basic end results of the function of the lockup are to increase fuel economy by creating a direct drive via decreased engine RPM, and to regulate the temperature of the transmission fluid by eliminating slippage as stated above.

An auxiliary external cooler is a good idea, but will not necessarily eliminate the need for a way to control the TCC. If you search around there is an explanation of how to wire a very cheap and simple switch via a jumper wire on the ALDL; some like the idea, some don't.

J0hn_J0hn08

iTrader: (2)

Thanks for the info.

Now in my case on the LG4 cars the computer tells the transmission when to lock up. Im looking to delete all the electronic quadrajet stuff. I really just want to keep it primitive and basic, its just my preference.

but from doing some searching, without the lock up the transmission clutches will burn up supposedly. So assuming that i rig up some sort of switch as a last resort when should the switch be activated?

is it on all the time? or from 3rd to 4th?etc?
basically when do u want the converter locked?

i really couldnt care less about fuel economy but i also am not looking to burn up the transmission. is there really no other options?

im really sorry for asking so many questions but its the only way ill ever gather any good detailed information on the subject.

Apeiron

Check the sticky in the carb forum.

z28romance

new one on me. you learn something new every day. thanks Apeiron.

vetteoz

iTrader: (13)

Before economy became a factor; no trans had a lockup convertor and there are plenty of TH350 and 400's out there running fine.
As noted above the convertor lockup takes out the slippage present in a non locking convertor so all engine power
goes to wheels instead of some being lost in the reg convertor'

If you have no concerns about economy ,you can install a switch in the trans that will automatically
turn on lockup as soon as and whenever trans goes into 4th.
You don't need a $200 "kit"

Apeiron

Three speed transmissions without overdrive back when a 3.23 gear was an "economy" ratio.

five7kid

iTrader: (14)

Torque converter clutch lock-up is controlled by a solenoid in the case of the transmission. Pressure to activate the TCC is supplied by the front pump (as are all auto tranny functions). However, the pressure is only supplied to the TCC when the tranny is in 2nd, 3rd, or 4th gears. The solenoid actually closes off the return for the TCC pressure passage, such that when the solenoid is activated, the return is shut off and pressure is applied to the clutch disk. When the solenoid is deactivated, the TCC fluid flow just returns to the pan.

12 volt positive power is always applied to the solenoid when the brake pedal is not depressed (applying the brake opens a switch and removes the power from the solenoid circuit). The circuit is completed by the ECM to energize the solenoid by grounding the electrical return. Some vehicles are programmed so that the ECM will not lock up the TCC unless the transmission is in 4th gear, sensed by a pressure switch in the 4th gear pressure passage in the valve body. My LG4, however, would lock up in 2nd or 3rd gear if conditions were correct (over 41 mph, manifold vacuum and throttle position within certain parameters, etc.).

The reason I told you all this is simple - you can get a pressure switch that is normally open, and grounds when pressure is applied. Reroute the ECM grounding wire for the TCC solenoid that is in the tranny pan to such a switch on the 4th gear pressure passage, and you'll have TCC lock-up whenever the transmission is in 4th gear and the brake isn't applied. When you hit the brake, the TCC will unlock.

But, since you're dumbing down your car and don't really care about fuel economy, why don't you just put a TH350 or TH400 in your car while you're at it? Then you won't have to worry about these things.

Of course, if you kept the computer controls and spent your time & money on what is really holding back performance on your car, you'd have a better car in the end. But, if you really want to go primitive, it's your car, your money, your funeral.

"Primitive" is why 14-sec "sports cars" used to get 10 mpg. "Electronic stuff" is why 12-sec daily drivers will get 25 mpg today.

ChevyRS-305

Well see here im going the route of eliminating the computer but still keeping the 700r4. A while back my transmission clutch pacs burnt up after 22 years and the tranny shop rebuilt the whole thing for me and "locked up" over drive for me. My worrie is when i take my computer out that it wont lock up. Since the solenoid is locked up because of a electronic power source, when i remove the computer i will remove the power source. Correct?

vetteoz

iTrader: (13)

No
Power still goes to TCC ;you loose the ground to the computer that controls it
Do the internal mod five7kid mentions in his post above and it solves all your problems

ChevyRS-305

So do i connect c451 to a toggle switch and then to a ground, and then connect c452 to a 12v power source?

ChevyRS-305

The reason I told you all this is simple - you can get a pressure switch that is normally open, and grounds when pressure is applied. Reroute the ECM grounding wire for the TCC solenoid that is in the tranny pan to such a switch on the 4th gear pressure passage, and you'll have TCC lock-up whenever the transmission is in 4th gear and the brake isn't applied. When you hit the brake, the TCC will unlock.[/QUOTE]



Im still trying to wrap my head around this. Also could i not just use the break switch that was used for the system originaly from the factory? And what prongs do i connect to on the plug on the outside of the transmission case?

vetteoz

iTrader: (13)

You should still have the harness and plug that went to the trans with the colors that match diagram above?
Just reconnect the pink to your existing brake switch and you have power at trans.
Ground the tan / blk control wire through a switch to operate TCC

ChevyRS-305

And all i would have to do is flip the switch when i go into overdrive

TreeFiddy

If you do very little mileage in OD, then tcc lockup makes no difference, as it only operates in OD anyway generally in thirdgen applications.

I drove my carb conversion with no tcc for years with no ill effects, but that was with virtually no highway driving. I hooked it up recently.

If you still have the factory wiring but with the computer removed - basically wire a toggle or better still vacuum switch between the tan/blk and light blue wires of the diagram a few posts up - or as per my first attached diagram.

The second attached diagram shows my actual setup. My PO had removed all the tcc wiring and the tcc brake switch, so I had to start from scratch. I could not find a N/O brake pedal switch anywhere, so I used a relay to invert the sense of the brake light switch for tcc use.

The vacuum switch is a nice refinement, so it doesn't bog down when trying to accelerate. Use ported vaccum, so the tcc unlocks when coasting. I just used a toggle for a while, but was always forgetting either turn it on or off - really annoying. This way it's all automatic.

I also wired up the 'Shift' light on the dash to come on with the tcc, not necessary but I though why not.

vetteoz

iTrader: (13)

Be aware, the early model T700's only had full fluid flow to the trans cooler when locked up.(WTF)
Running for extended periods without lockup could cause the trans to overheat.

NB
this is where the myth and confusion about needing the TCC came about from ;
many believing that running without it will burn up the clutches
As I noted above ;on the modified later versions running without TCC is no different than running a TH400

TreeFiddy

That's a detail I was not aware of. Did these early units then require lockup in lower gears as well?

freaky

just don't confuse the tcc lockup with the tv cable an the importance of it being set correct .

rmmstnr

Exactly, you can get away without a lockup circuit, you'll just have warmer trans temps on the highway and slightly lower gas mileage. An improperly set up Throttle Valve however can burn up your clutches and basically leave you without most of your needed line pressure for clutch and band holding while heavy on the gas.

To reiterate what was said in a couple posts, lockup is mainly during cruising in OD for mileage and heat reasons, and stock the TC locks up only in 4th. With manual control of the switch you can turn it on in any gear except 1st I believe, a plus if towing in 3rd or for extended cruising in a non-OD gear.

If you have a 700r4, here's a lockup kit for just under $90: http://www.tciauto.com/tc/200-4r-700...iring-kit.html .
Comes with everything except some extra wire for a 12V+ source. So figure a couple bucks extra for some wire, connectors, and vacuum hose. It's pretty easy to install, I literally just finished putting one in yesterday. There's even options for hooking up a switch to manually operate it and/or even add brake switch input like the OEM setups. You will need to open the trans pan though, basically to cut a couple wires and swap on a small harness that takes their place (just 3-4 wires), and replace a screw in switch. The white plug in the pic plugs into the case, and just needs a ground, a 12V+ wire, and if you want, a wire to a grounded dash-mounted switch for manual control. The black thing is an adjustable vacuum switch that plugs into the white plug, needing only a vacuum line.

Just remember to check if you have a 1 or 2 wire TCC Solenoid first, the kit is for a 2 wire.

BTW, lockup converters have actually been around for awhile. I believe were first used in Packards or something similar. Later came the Buick Dual-Path, an aircooled 2spd where Hi gear was engaged by locking up the trans' innards from torque converter to output shaft. The torque converter was pretty cool: you could take it apart, the front half was finned aluminum (the case, stator, turbine and impeller were too), and the planetary gearset (just one) and lockup clutch pack were located inside of the converter. Being air cooled, locking up the converter was a great way to keep the trans cool

As cool as it is, I ended swapping it out for the 700r4 I just installed the kit on. Still have the 2 spd though

vetteoz

iTrader: (13)

I always though one of the more interesting designs was the switch pitch convertor used on the TH400 in mid 60's Buicks and Olds
Gave both 1800 and 2800 stall

A reasonable stall for acceleration and a stockish stall for cruise

rmmstnr

Wonder why they got rid of that, seemed like a really cool thing to have on a trans. 'Course, GM also got rid of the turbocharged aluminum v8, the air-cooled flat 6, a couple different v16's, an aluminum 454, and put that awesome 4.5l diesel v8 on hold "indefinitely," so I guess they thought the general public just has trouble accepting awesomeness. Then again, looking at history it seems that the general public does have their problems with cool stuff at times

ChevyRS-305

I went ahead and gutted all the old wiring harness inside and out. I decided to make my own custom harness where everything is stand alone on toggles. I have however found a stand alone tcc lock up by tci for like $80. Vary easy to install and well worth the money. http://www.summitracing.com/parts/TCI-376600/

InfernalVortex

iTrader: (4)

Well... doesnt have to be a 4th gear.... In a manual the overdrive is the 5th gear. In the case of the T56 it's the 5th, AND 6th gear.

I think overdrive is any gear that turns at least that one output revolution vs an input revolution. Normally this kind of clarification doesnt matter, but we are now living in the days of 8 speed automatics ...

InfernalVortex

iTrader: (4)

Probably reliability, manufacturing cost, maintenance costs, emissions problems, or fuel mileage problems (CAFE).

1993 700r4

So I got a 93 Chevy k 1500 Z71 burned up tranny (4l 60 e) for 250 bucks runs great got a free 88 Chevy k 1500 with a 700 r4 I put the 700R4 in the 93 hooked up the TV cable switched the reluctor for the 4 l 60 e one so i have Speedo my question is should I just get a tranny temp gauge and if my tranny gets too hot just shift to 3rd for it to cool down when towing trying to be cheap here

MSgt Luttrell

I went with a level three built 700r4, with a nonlock out converter in my IROC, it still has a fourth gear, just no lock up converter.

Fast355

iTrader: (2)

Tow in 3rd...The most reliably and cheapest option.

My 83 and 92 700r4s locked the TCC with the factory setups in 2nd, 3rd and 4th. Hook your lockup up and tow in 3rd. Will build far less heat and put much less stress on both the converter and OD planetary and clutches.

Drac0nic

The issue with lockup burning the boxes up was supposedly only on the early transmissions.

Here's a way to hook up the TCC using a vacuum switch, a few relays and tying into existing circuits. The part is 14014519 GM which is a vacuum switch that senses low load. It's supposedly discontinued but look around and you can probably find an alternative somewhere like digikey or build a comparator circuit that uses the MAP Sensor load. Post recycled from another forum I put this on:



How the circuit works is as follows:The pink/black wire is energized when the key is in the "run" position. The vacuum switch turns on when the vehicle is pulling significant vacuum at low RPM. The fourth gear switch is connected to a chassis ground in the case. When the switch closes, this allows the relay RLY1 to energize and the converter clutch solenoid. The relay RLY2 serves the function of disconnecting the converter clutch solenoid when the brake pedal is pressed as actuation of the brakes when the converter is engaged is hard on the clutch in the converter.

Fast355

iTrader: (2)

My early 700r4 was wired differently. It locked in 2nd and 3rd off the vacuum switch that was connected to ported vacuum through a TVS that blocked vacuum under 110°F. 4th gear locked off the 4th gear switch. The 4th gear switch was also wired through the EGR bleed solenoid which bled off the signal to the EGR valve. Q-Jet version of lean cruise.

Drac0nic

Interesting. I didn't know they had a temperature component. That diagram isn't based off an OE configuration, it's based off just the raw logical steps I determined would enable a 700R4 to lock and do so safely.