marlinspike

So, the car in question is a modified 80s Mercedes, but I've read that some of the 928s used a Mercedes 722.3 torque converter. Anybody know of a replacement with a higher stall speed (more like 2200rpm rather than 1800 rpm)?

RngTrtl

I know that there is somebody here that modifys the TC to increase the stall speed, but I dont recall offhand who. Maybe a search will turn something up.

killav

I don't know what model a 722.3 would fit but I had my converter modified for increased stall. If you search my user name and look at my posts back in circa 2006 you will find my post about it. See my signature for year and model.

killav

https://rennlist.com/forums/928-forum/295382-i-got-my-torque-converter-rebuilt-with-increased-stall.html

PorKen

ROW autos had a higher stall speed, IIRC.

atb

I think the LH 16v's in particular ('84-'86).

marlinspike

Someone once told me there is a way to do it by simply modifying the valve body. True?

bd0nalds0n

Edge racing converters will re-fin the converter to raise the stall speed.

www.edgeracing.com

David L. Lutz

Edge just did mine and I finally drove it for the 1st time day before yesterday for about 30min.. Much more responsive off the line. I think he charged me around 300.00 dollars and it took about 2 weeks. Fuel pump went bad and I haven't been back on the road since.

porsche928guy

David...can you double check that price? They charged me $425 and you are the second person now that just recently reported a lower price.

David L. Lutz

Jeremy,

Edge charged my Visa in the amount of $362.00. That paid for them shipping it back (which was around 60.00) and for the modification. I paid separate for the shipping charge when I sent it out.

Hope this helps.

By the way, do you have any vibration after your converter was modified. I say this because I seem to be having a vibration that increases with RPM. I am not sure if it is the Torque Converter or Torque Tube. I also rebuilt the torque tube. ??

David L. Lutz

Bump for jeremy!

porsche928guy

Dave,
YES!!! I'm trying to dealing with that now. I'll PM you my phone number and we can talk about it if you want to call me. I'm getting a good (or in this case bad) vibration around 3K in every gear and in park. I'm thinking its either the TT or the TC (what else could it be?). I called Andre and asked him about it and he told me that sometimes vibrations were there all along but with the tighter tolerances now in the TC they are being transmitted back through more easily. Keep me posted...I REALLY don't want to take this all apart again!

David L. Lutz

Jeremy,
Check your mail.

Boy is this weird. I too replaced my Torque Tube, used the Constantine Clamp $$ and also replaced my Tranny mounts. The engine mounts were replaced last year. You wouldn't think there would any vibration. Since my rings are new I didn't get a chance to run it above 4000 rpm, but as the car passes 2800 - 3000 rpm the vibration starts. I can really feel it in the gear shifter. I got under the car and revved it up to around 3200 and putting my hand on the tranny could really feel the vibration.

I think I saw somewhere here where it was best if the converters were balanced with fluid. I too was going to call Andre to discuss this.

Also I read where we could disconnect the flex plate from the drive shaft in the rear (at the converter) run the engine and see if the vibration is still present. If so its being caused in the torque tube or somewhere else.

Let me get my fuel pump back in the car and check a little closer and I will call you this weekend.

Maybe we should start another thread so we could see if anyone else is having this problem with Edge converters.

By the way, I am 100% sure my car did not have this vibration before the tear down and replacement of said parts.
David

Mrmerlin

did you refit the TT vibration damper between the rear bearing support and the center bearing support??
Did you try to turn the rear flex plate one space on the torque converter? this might cure things as usually the driveshaft/torque converter are all balanced