Sarum

Hi there, I desparately need some input from someone who has expert? knowledge in regard to the TH350C lockup operation. I plan on converting the TH350C in my '65 Cutlass to a TH350 and have started the ball rolling by removing all of the wiring and components that are attached to the underside of the valvebody and blocking up the relevant holes.I am seeking clarification that I am right in thinking that the port that has the electromechanical valve covering it is normally blocked off and trans fluid only flows through this port when the lockup feature is functioning.
If what I have just stated is correct I will be able to use the car normally until the transmission is removed and the input shaft.pump etc replaced.I would appreciate any helpful comments in regard to this conversion and the valving especially.Thanks in advance!

matt69olds

As common as th350 transmissions are, it would be far easier to simply useza 350. B&M use to offer a kit to convert the 350C to a standard open converter i havemt seen that kit in years. Im not sure what all needs to be changed or modified

Sarum

Thanks for your reply but it woul cost me $1500-$2000 to buy a TH350 as good as the trans that is in the car now. It's looking like I can just cut the lockup part of the input shaft off and fit the TCI high stall TC that I have sitting in a box. Still would like an answer to my question though.

matt69olds

How can you have 1500-2000 in a TH350?! Where are you located?

olds 307 and 403

I have a used 2500 stall TH350C you can have for shipping cost, your call. I am pretty sure the oil feed needs blocked off as well. So few people bother with this mod since there are so many no lock up cores still out there.

Sarum

Sorry for the delay in replying, my laptop permanently died. To answer your question I am in Matamata, New Zealand.Matamata is also known as Hobbiton if you are into Lord of the Rings.Cheers

olds 307 and 403

Cool place to live.

Sarum

Yes, it sure is.We shifted from Auckland to Matamata almost a year ago now.It seems like every time I watch the news these days I am thankful that we live way down here out of the way of all the never ending madness.

Sarum

It looks like I am going to have to put the lockup valve electronic components back in because everytime I put the car into Drive or Low the engine stalls. You can "catch " the engine if you time it right and floor it but if I have to stop i have to throw the trans into Neutral to avoid stalling.It may well be that the electronics work in a different way from what I had thought and that the trans (still as a TH350C) needs the valve installed to act as some sort of bleed - valvebody to pan.

Sarum

1st go with my new laptop! Thanks so much for your kind offer but I am hoping it's not too expensive to convert my TH350C to a standard TH350. For now I am trying to figure out why the engine is now stalling when put into Drive
From addition to post
It looks like I am going to have to put the lockup valve electronic components back in because every time I put the car into Drive or Low the engine stalls. You can "catch " the engine if you time it right and floor it but if I have to stop i have to throw the trans into Neutral to avoid stalling.It may well be that the electronics work in a different way from what I had thought and that the trans (still as a TH350C) needs the valve installed to act as some sort of bleed - valvebody to pan.
As the car sat with its nose high up in the air with no pan on the trans maybe something has frozen up because there was no trans fluid.
Thought = Is it possible for fluid to drain out of the torque converter with the car jacked up high at the front for a longish period?