200-4R lockup or non lockup?

[ChevyIIMan]

I found a working decent mileage 200-4r pulled from a 85 Monet SS. I plan on swapping it into my car and rebuilding it at a later date. Now for my main question.



By nature this is a lockup transmission correct? Ive seen many wiring kits to adapt it to older cars thats not a problem, what I am wondering is how would you convert it to non lockup? And which is better in the end?

[astroracer]

Just my .02's but disabling the lock up function defeats the purpose of a 4spd overdrive trans doesn't it? Without the lock up it won't go into 4th gear which is the O.D. gear. The wiring kits give you everything you need to make it work correctly with overdrive. I don't see any reason to disable it... it will not help performance in any way.
Mark

[ChevyIIMan]

Thanks that what I was looking for.... ill proably end up with a wiring kit now to decide on which one

[TPI Monte SS]

Just my .02's but disabling the lock up function defeats the purpose of a 4spd overdrive trans doesn't it? Without the lock up it won't go into 4th gear which is the O.D. gear. The wiring kits give you everything you need to make it work correctly with overdrive. I don't see any reason to disable it... it will not help performance in any way.
Mark

Not necessarily. The 200-4R will still go into 4th gear, but the converter will not lock up. This could generate extra heat and eventually cook the trans. I've driven with the lockup disabled for a few weeks when the lockup solenoid in the trans was acting up with no ill effects.

The wiring kits will get a stock (or aftermarket) converter to lock up, provided it has that provision. There are non-lockup converters on the market as well. Check out http://www.2004r.com for some more detailed info.

[ChevyIIMan]

What are the advantages or disadvantages of havingh lockup then? So your saying to run non lockup just buy a non lockup converter and forget about it?

[TPI Monte SS]

Check this link out - http://www.technicalevolution.com/tcc.htm - it explains the benefits of a lockup converter.

And scroll down to the bottom of this link - http://www.gnttype.org/techarea/tran...onverters.html - explains the differences between lockup and non-lockup converters. Both are good reads, and pretty short.

Basically, a lockup converter is slightly less responsive and can wear out sooner in higher HP/TQ applications, but will return better mileage and cooler trans temperatures. A non-lockup converter trades off some heat and effiencency for more response. I'd go for the lockup style if the car is a driver with a moderate power level.

[ChevyIIMan]

Yeah its just a SBC 400hp/400tq motor nothing crazy, and a cruiser and maybe race2 or 3 times a year

[astroracer]

Just keep in mind that you'll probably fry this stock trans if you do any "power shows" or beat on it frequently. A used, stock 200R4 is not going to take much abuse...

[ChevyIIMan]

It going in the car for a short time before it will be pulled and rebuilt

[myclone]

FWIW dept...

Keep in mind that a 200R4 as well as the 700R4 require a few more mods besides swapping the lock up TC for a non lock up unit. There are some passages that need to be blocked in the valve body as well as some other minor things. Its not a huge deal to do for someone with moderate skill level but something to be aware of if you go non lock up.

A well prepped 200R4 can go mid 10s on a regular basis and a few of the turbo buick ppl have gone low 10s (possibly 9s) with units that are freshened seasonaly. In a vehicle thats producing 400hp/tq a healthy 200R4 should last quite a few years if fed a steady diet of clean and cool fluid.

For the application in question I personally see no benefit of using a non lock up TC unless you get free gas and if thats the case a TH350/400 will out last the engine, car, and probably the owner in life span.

[ChevyIIMan]

Ill most likely go lockup, im trying to make this car a cruiser now.... tired fo blowing stuff up..

[blown69nova]

ChevyIIman if your interested, I have a Precision Industries 9" 2800 stall lock up converter for sale. Only about 3,000 miles and 5-6 low 13 sec passes on it. I'm switching to a TH400 for my new supercharged setup.$375 obo.