Torque Converter Stall

kilkm68 · 12-10-2012, 09:58 AM

I'm interested in what stall speed torque converter guys are using in their street machines (not race car). I might want to have my tyranny freshened up over the winter and would like some suggestions. I know there a lot of factors to consider but would like to just get a ballpark figure. My cars a street toy, mostly just a show-off cruiser but I also sometimes need to put my big-mouthed cheby buddies in their place. I have a '68 GTO with a Butler 474, 500+ hp, Art Carr 200 4R tyranny and 373 gears. Tyranny was in the car when I bought it, all I know is it has a Gomez? converter not sure of the stall. Any suggestions?

BearGFR · 12-10-2012, 07:46 PM

If you've got a turnkey Butler powerplant, then I'd say you should ask them for a converter (and rear gear) recommendation. They ought to know more about where it will be "happy" than anyone.

But, since you asked, my 461 has a 3200 rpm converter behind it. I wouldn't go any looser than that. At 3200 rpm in high gear, the point where the converter stops slipping, I'm at 70 mph with my gears and tires. Whatever you choose, you'll want it to NOT still be slipping when you're at highway cruise rpm, whatever that works out to be for your combination. Otherwise you run the risk of overheating the fluid and starting to cook transmission parts. Most of the heat that gets generated in a transmission comes from the converter.

Bear

geeteeohguy · 12-11-2012, 02:41 PM

Good point, Bear. With an overdrive trans, kilkm would likely need much less stall to avoid slippage at cruising speeds. The converter I used in my '67 is a bit higher than stock, but still at or just under 2000 rpm....which is a good thing since my 70mph rpm is about 2100 with my lazy rear gears.

ALKYGTO · 12-11-2012, 05:25 PM

Read this - Torque converters for street and strip

pretty comprehensive article on converter type and selection by Jim Hand.

I originally was going to suggest a switch pitch converter. I had a good friend with an 11 sec Buick who had one and it worked very well. I believe he sourced it from Poston Ent. if they are still around.

kilkm68 · 12-11-2012, 08:37 PM

Thanks guys, great info. Final drive on this 200 4R I believe is 0.78 coupled to a 3:73 rear gear. At 55 it runs about 1900 at 70 about 2600 - 2800. Think I'll try changing the fluid and filter and adjusting the TV cable and see if there is any improvement. I'm getting some occasional slippage when you kick it hard and it down shifts. Motor revs and some hesitation before it grabs. Could be in the TV cable adjustment maybe.

66 Gas Tires Oil · 12-13-2012, 02:08 PM

When you have your torque converter built the builder goes through a checklist and builds to your spec. there is no one size fits all for an engine. do not buy a b&m type. if your on a budget, Red max can do you good. you should read up on torque converters also. a 2004r can use a lock-up but must be wired for one in the car because there is no computer and sensors to tell it what to do. their is balloon types for NOS and also different diameters depending on application. before you call you need to know the rear ratio, the rear tire height, tranny type. RPM to shift. intended use for the car. that way you get exactlly what you need. otherwise you may go through a few of them. not fun and expensive.

Jim