42RH SWAP

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modart440

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I have a 68 Dart with a 408 and a 727 trans. Looking between the GV and a 42 RH swap. I'm in Canada so at 35 cents on the dollar the GV gets real expensive. I have a 42RH out of a 90 v6 Dakota. I dont need a lockup convertor so I'm curious if the 42RH can be modified to accept a regular 904 convertor? (Higher stall).I'm aware of the fitment and chassis mods required.
Thanks
 
Not sure you can do that with the converter. Kinda defeats the purpose of an OD trans if you ask me. just dont hook up the overdrive and no lock up.. But then why bother installing it then. Send it to me, i need one.
 
I put a 42RH in my dart. No way the old 904 converter would swap, but it looked like the pump bolt pattern was the same so maybe you could change stuff around and make that work... but I don't know. I wouldn't have gone to the trouble of the swap and not use the lock up feature.
 
A discussion on here some time ago pointed out that using a non lock up with OD would likely cause a situation where the converter is "cruising" below the stall point, and therefore would slip and cause heat
 
I have encountered several non-lockup 518's.
ok thanks for the replies.I'm running a 408 360 based engine(LA style) what about converter balance and what flexplate? Based on running the factory lockup converter.
thanks
 
ok thanks for the replies.I'm running a 408 360 based engine(LA style) what about converter balance and what flexplate? Based on running the factory lockup converter.
thanks
Also who's rebuild kit to use.
Thanks
 
They (could) have a lesser clutch plates in the OD and a few other things I recall.
I daily drive with a non-lockup 518 in my '73 Dart.
No issues with the non-lockup and driving slower than the (stock) convertor's stall speed.

I can 'switch on' OD at anytime the trans is in 3rd.
I can also coast down to say 20-25mph and flip the OD-switch and have the engine 'idle' at around 7-800 rpm while still moving nicely. Not the most efficient way to drive but it sure is 'quiet'.
 
The answer to this question of can it be done with a regular 904 converter is YES it can, been there done that. You need to press on the non-lock shaft. Although my issue with it was cruising the same RPM going up a hill at 60 as i was cruising flat at 70. I had a PTC 3500 stall so that could contribute.

It ran fine for 3 years and 5,000 miles.... Until I replaced it with a manual. If I had it to do again I'd probably run lock-up, but I was paranoid I'd twist that measly input shaft off..

My unsolicited advise; get a good quality wide front band, go to the tight side of factory tolerances and thoughtfully build the OD section from knowledge on diesel 518's since they share the same OD section.
 
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The answer to this question of can it be done with a regular 904 converter is YES it can, been there done that. You need to press on the non-lock shaft. Although my issue with it was cruising the same RPM going up a hill at 60 as i was cruising flat at 70. I had a PTC 3500 stall so that could contribute.

It ran fine for 3 years and 5,000 miles.... Until I replaced it with a manual. If I had it to do again I'd probably run lock-up, but I was paranoid I'd twist that measly input shaft off..

My unsolicited advise; get a good quality wide front band, go to the tight side of factory tolerances and thoughtfully build the OD section from knowledge on diesel 518's since they share the same OD section.
What would be a good quality wide front band?
Thanks for the reply
 
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