stevechumo

iTrader: (5)

I read somewhere on some dyno shops that higher stall speed on the TC will lose some power to the wheels. If that's true, you'll lose some more rwhp and that means you'll need to boost more to make up for that loss.

KC95SC400

iTrader: (3)

Actually, I have yet to ever speak to John. I always deal with Ty (spelling?). No matter, he seems to know what he's doing and is easy to deal with.

I hear you. After breaking the converter I started doing some searching and had found quite a few accounts of them breaking. In my case, I had abused the heck out of it and can't say I'm terribly surprised it broke. At this point, I'm far more dissapointed with PI's customer service than with the product itself.

I've seen much debate on this. It seems though that a GOOD converter won't have this problem. And, if you can lock the converter on the dyno it's a mute point anyway.

I can tell you that I went to the track with the stock unit back in and trapped a little higher than normal BUT, it was also quite chilly outside which probably had more to do with it than the converter / stall change.

Regardless, the car is faster with a higher stall on the track since it can be launched harder, resulting in faster 60ft times.

-------------------------------------------------------------

Updates:

Still have not heard a thing from PI even though they got my converter back early Thursday afternoon. Tried to call them Friday and it turns out that they are closed on Fridays. I plan on calling them later today if I don't hear from them first.

Talked to the guy building my transmission on Friday. He found two broken parts. One of the piston return springs was broken and the second gear pressure plate was broken. He had to order the second gear plate and said he should be able to have it done today, assuming he gets the part.

He also asked me where I got the rebuild kit saying it appeared to be good, high quality stuff.

KC

spin all 4

Well, I mean you were abusing the converter but that's what this stuff is designed to do. It's not like you're beating on a $100 re-stalled stock converter. And It's not like the Lexus V8 is a torque monster on bottom where the converter is stalling at either, even more so with the centrifugal blower.


As for the lower numbers with a high stall on the dyno, I see this all the time as my friends have a shop with a dynojet. The stalled cars always put down less HP, but are usually quicker at the track. We've seen this on a lot of v8 cars that you can't lock up. I believe the dyno is just thrown off by the the torque converter doing it's job and stalling.

As far as the 4000 stall debate, you can drive a 4000 stall on the street. It will probably mess with the MPG at cruise, but you could always build a lock up switch if the supra stick doesn't already have one. I guess you just have to decide how rowdy you want the car to be.

KC95SC400

iTrader: (3)

FYI, when I say I abused it, I really have. Not trying to defend them but.... The converter had over 220 track passes on it before it broke. And, the last 80 or so passes (since installing the Suprastick) were with the converter locked and staying locked DURING shifts. I think the locked while shifting is probably what really killed it. Puts allot more stress on both the converter and the transmission.

To me, track times say more than dyno numbers. The track is real world. I also think that the coverter needs to be locked to get the most accurate reading. I remeber seeing an article somewhere stating that most dynos are setup for manual cars but the program can be changed to account for an auto's stall speed. I think it's like you said, the dyno is thrown off if not calibrated for it.

For the stall, I went with the "next step up". Was told this would be around 3400-3600 rpm. I think this should be about right. I can have it lock whenever I want with the Suprastick which should help keep gas mileage about the same.

There is a big import meet at Rockingham dragway this coming Sunday. Hopefully, if everything finally falls into line, I'll be there. Hopefully with some new kick butt times to report.

-----------------------------------------------------------

Update:

Finally got some info from PI. They agreed that it wasn't fixed the first time. I was told that it would be fixed today and overnighted back to me. Should have it tomorrow.

Still waiting on some info from the transmission builder. I will likely call him by the end of the day if I don't here from him first.

KC

stevechumo

iTrader: (5)

PI should have paid for your shipping due to their mistake. That thing is heavy, so it'll be quite some shipping fee there.

I have a question for you since you have similar setup as mine. Do you have any oversteering issue when launching the car? I have that issue and still can't overcome that yet. It happens either with brake-torqueing or just flooring it from the beginning. This happens more right after I got my tranny rebuilt with the HP kit and the shift kit from IT. I guess the tranny kicks in so hard and causes this. Or it could be too much torque at low end.

KC95SC400

iTrader: (3)

No, don't have that problem. Do you have an LSD of some sort? I don't have issues even when hooking well on the track.

It does sometimes feel like the rear might come around during a spirited 1-2 shift while in a turn though.

I have been emailing back and forth with PI allot today. They have apologized quite a few times and they are telling me I'll have the converter back by tomorrow.

Also, in the middle of posting this, the trans builder called and said the transmission is done. I'll pick it up tomorrow. Was sick yesterday and called out from work today so I'll just wait.

KC

stevechumo

iTrader: (5)

I do have a Supra Torsen LSD and it helps with hooking the tires. But I don't like the oversteering much. It's a scary feeling.

KC95SC400

iTrader: (3)

I'm not 100% sure what you mean by oversteer? Mine has always gone more or less straight during a straight launch.

I'd maybe look into suspension components? Wheel hop? Stuck / sticking brake caliper? Differentail bushings?



KC

KC95SC400

iTrader: (3)

Updates:

Mentioned earlier that my trans is ready for me to pick up. I'll pick it up tomorrow sometime.

PI has apologized many times, fixed my converter today (in theory LOL) and shipped it next day air. Have to give them credit for the shipping. Looked on UPS.com, probably cost them $140 dollars or so to do that for me.

I won't likely be able to put everything in until Wednesday. I'll try and take some pics.

KC

KC95SC400

iTrader: (3)

Installed everything today. Not yet 100% sure on it.

When I first started it, filled the fluid up and drove it, something was definately not right. I drove maybe 500 feet and parked, then I had to go do something else for about an hour. When I got back to it, was much better so I drove it around the block to heat the fluid some. Got back in the shop and checked it, was ok.

Seems fine but feels completely different, mostly in first. I think it may just be the stall change throwing me off. It is shifting very fast and hard even with lightish driving just feels a little funky in first. It's been raining here for a couple of days now so I can't get on it at all without breaking the rear tires loose. I think, with a completely dry transmission, it probably had some air / foam in it from the initial start which went away after I let it sit for awhile.

I'll update some more once I drive it a bit more. Converter was fixed this time BTW.

KC

KC95SC400

iTrader: (3)

Ok guys, update.

Warning, you'll really need to give a crap to follow all of this.

For reference:

TA (transmission A) is my newly rebuilt unit with Raybestos blue plate clutches and the IPT second gear sprag.

TB (transmission B) is my spare stock transmission.

TQA (converter A) is the fixed PI converter.

TQB (converter B) is the stock converter.

I had TB and TQB in since I broke the PI converter and the other transmission. Got both back (and fixed) and installed TA and TQA on Wednesday of last week. Had a weird noise in reverse and didn't quite feel right. So on Friday I tried putting TQB back in with TA. Felt better but still had the same noise so on Saturday I put TQA in with TB. Still had the same noise! At this point I'm like WTF?!? Had no noise before now I have a noise with every combination. The only thing in common when swapping the trannies being the valve body. Today I put both TA and TQA back in, everything feels great and so far no weird noises.

When I put the new stuff in on Wednesday I had also installed the Megan mounts. Maybe has / had something to do with the noise, I don't know for sure. The noise is / was at it's worst when cold so I'll know tomorrow morning for sure if I still have a noise or not.

Also worth noting that when I first installed TA and TQA I filled with M1 synthetic trans fluid. Every time I swapped stuff around I'm sure less of the fluid was M1 since I was using T4 to re-fill. When I swapped everything back today, I used Dex3 and also flushed with Dex3 once everything was in and I was sure everything was working.

So, long story short, this is why I didn't make it to Rockingham on Sunday. Sucks cause I really wanted to go.

Sorry if it's all confusing but I did warn first!

KC