Anyone using a Yank converter?

[lazaris]

Im running one. I had a 3600 extreme. I wanted more stall and it locked up a little to early. I sent it back for a 4000 stall and later lock up. See my sig for the times. Ive gone 1.46 60' on the footbrake. With a little less spin I think I can go a low 40. I really like this converter.

 

[ijames]

I put in a TurboThruster 3000 with the standard clutch and after about 50 miles (there weren't any instructions with it) did some foot-brake/build boost tests. Converter was very tight, stalling at 22-2400 rpm and I could only build 2-3 psi boost. Then it started making a screeching noise under boost so I pulled it out and sent it back to be checked. They said that it looked perfect inside, and asked why I hadn't broken it in for 150 miles like the instructions said. Naturally my response was "what instructions?" . Also, they said that they had never heard of one making a noise like that. It's kind of a scraping, screeching noise. Got it back, put it in, and babied it for 175 miles. However, running in city traffic if I made maybe 2-3 psi boost in 2nd or 3rd (just enough to keep up with traffic) it would make the noise again. Called them and they said to keep driving it and again said that they hadn't had one make any noise before. Oh, the instructions say no wot launches or shifts for 150 miles. After 175 miles I went to the track and did two launches. Behaved just like before, very tight, only got about 2500 rpm and 3-4 psi boost. Put another 300 miles on it and it still made the same noise but suddenly started getting looser and looser. Over the course of literally 3 days the footbrake stall went from 2500 to 3500 rpm!. Now I can build all the boost I want, at least 10-12 psi. Went back to the track and make two passes. Launches were great (for me, anyway). Very fast spoolup and 1.86 sec 60' times (compared to 2.0-2.05 with my 2800 stall modifed D5). However, only ran a 13.36 at 99.5 mph, pulling 5400 rpms at 99.5 mph according to DirectScan. Second pass was a carbon copy. I lost 0.8-1.0 sec and 9 mph or so! Talked to Yank again and we are all very puzzled right now, but did say that they have a few Buick people with similar looseness problems and I think one other person is getting the noise.

One question that came up was what line pressures are we Buick guys running in the trans. I know that the stock pressures are 200-220 psi in 3rd gear at wot, and Yank said that this was what they use in the 200-4R's that they build to put in LT1 and LS1 F-bodies. I have an Art Carr shift kit in my transmission. Does anyone know what that raises the line pressure to?

 

[REDS HOT AIR]

there is nothing to break in in a t/c


when the stall changes it's broke
either fins folded or housing bolooned

 

[Steve Wood]

Actually, one is supposed to break in the clutch material in a Yank.

That was what was in Carl's missing instructions.

 

[ijames]

Yes, the Yank has a carbon ceramic clutch that needs to seat itself by polishing the pressure plate before it has full grabbing ability. In the Yank they leave out the bearing between disc and pressure plate (or something like that; I'm not exactly sure where the bearing is or if it's called a disc and pressure plate in a converter ). That way as the torque rises past about 475 ft lbs the clutch is automatically (and smoothly and gradually) applied at WOT. That feature is what sold me on the Yank, after a ride in Tim Dirks' car. Tim has the Kevlar clutch which can take even more power; originally they told him that it didn't need any breakin but now they seem to be saying the same for both. One price for that is that the clutch is partially applied while you are brake-torquing on the line, so as it seats the stall is supposed to rise 2-300 rpms (not 1000).

So, does anyone have any input on the line pressures? Yank was concerned that we may be balloning the converter with line pressures much higher than they expected. Thanks.

 

[WE4]

We are running 300 psi or better now and not ONE reported problem with the PTS Xtreme or 9/11.

 

[RickWI]

I'll vouch for that.

 

[REDS HOT AIR]

Originally posted by WE4
We are running 300 psi or better now and not ONE reported problem with the PTS Xtreme or 9/11.

no problemes with mine..

from what im reading about the yank it sounds more like a centrifical clutch than a t/c..

 

[Steve Wood]

Originally posted by REDS HOT AIR


no problemes with mine..

from what im reading about the yank it sounds more like a centrifical clutch than a t/c..

It's really not dependent upon centrifigal force but the idea is similar, I think.

When the torque coming thru the converter reaches a certain level, say 475-500 ft-lbs, the hydraulic force trying to separate the pump from the turbine forces the turbine into the clutch. This creates a bit smoother lock up.

Initially, this was only available in the pro extreme series.....I wonder if they miscalculated on the Buck 3000 models?

I would think under normal circumstances that it should not lock up early as Carl has experienced but should wait until the torque level has risen....unless Carl is making that kinda torque at 2500 rpm....