Transmission, Automatic

Stall Speed Increase

Stall Speed Increase

I have an 85S Auto with RMB, chip upgrade, K&N, polished intake and throttle was ok, but off the line it was just not very exciting (sound familiar?). then it developed a "clunk" under the front end when starting out from a dead stop - not the kind of excitement I was hoping for!

After repeatedly asking if the torque tube was ok ("oh you bet!"), I had spent over $6k on everything from motor mounts to a complete front suspension and steering system overhaul (spread out over 3 shops). "clunk" was still there until another shop finally fried my 1st gear clutches trying to "find" the problem.

SO - I took Clunky Shark to a tranny shop where they also said my torque tube was "probably fine"...after a little pursuading ("JUST PULL THE THING OFF!!") - they only found dust where the front bearings used to be!!! adios Clunky Shark - hello $ilent $hark!!!

the REALLY big news:
since I finally had someone's attention (other than my wife and accountant), and we were all on a 1st name basis by now, I had the torque converter overhauled and stall raised about 400 rpm from the stock 1650rpm to about 2000rpm...

WHAT A DIFFERENCE!!! Silent Shark has balls!!!!
done properly, the torque converter change will transform your Shark into a VERY QUICK (but still smooth)Shark!!! It was easily the best $375.00 ever spent on a performance upgrade!!! This Shark MOVES!!! Just tighten up the throttle/trans cable, crank down the vacum modulator and hang on!!!

the science is simple - you are putting the engine further into the power curves before you engage the drive train - like revving the motor more before you drop the clutch in a manual trans car.

but be careful on this one - if you go too gung-ho on raising the stall (to 3500 like a race car I once built), you will be on a first name basis at your local tire, chiropractor, and tranny shops...your shark will also be totally unusable on any wet surface due to insane tire spinning starts - cool until performed in front of Johnny Law (trust me on this one)....

Now I only have to listen to "how can you spend $9k on an $8k car?" from my wife and accountant...what? BWAAAAA!! I caaannnn't hear yooouuuu!!.....

No Hands!

Rob Rossitto
Grey 85S

That's a good idea. I'll be sure to pass it along. Does the torque converted get replaced to raise the stall speed, or does it get modified by the shop?


Modified only, by a rebuild shop...I believe they added some shims to increase the RPM's required to cause it to engage...allows a little extra "rev" prior to actually moving the car, hence the higher torque & HP when it finally does "catch" around 2k rpm, you can still easily control launches in order to maintain smooth starts on slipperly (wet, etc) surfaces, if desired - but if you go too high, you will lose that capability, and turn the car into a dragster....(of sorts)....most cars are at about 2400 rpm, but the 5.0 has such good torque at low rpm that we can stiil use a number that is lower than "normal" cars in order to preserve that "sport touring" feel (as opposed to a harsher, pure sports feel)...if I had the time, I would probably have tried even higher, maybe 2300 or so, just to see what would happen…

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