tomtnc

FYI...I should have learned my lesson from previous daily-driver cars with performance modifications as intrusive as this...never a good idea with regards to longevity. After 50K miles from install, the drivetrain developed a "clunk" at higher speed when applying gas from a cruise state. Eventually the check engine light came on and the code read was a transmission shift solenoid failure related to a torque converter lock-up failure / problem. Fortunately I saved the stock converter and simply swapped the parts out to fix all of the drivetrain issues. The check engine light is off and the car runs perfectly. It actually shifts better with the 3.73 gearing...no more "slipping" between the 1-2 shift on full throttle acceleration. I know a lot of you are fans of the PI converter, but I never saw the performance gains in real life that were claimed. Certainly, it caused me a lot of drivetrain issues which could only be solved by replacing it with the stock converter. For those considering this modification...fair warning.

TLcoats

iTrader: (11)

Dang. And i was thinking about doing this mod. Could anybody back up these claims or contest them?

Rock-a-Lex

iTrader: (4)

WOW! This is crazy...so you mean to tell me that you feel NO diffeence in off-the-line acceleration now that you have the stock torque converter back in there? Also, did you have a standalone transmssion cooler?

Alexus_300

iTrader: (4)

Welcome back Tom. Been quite a while since I've seen you post on here. As far as the PI torque converter goes, I've heard alot of quality issues with their tq converter. I have one of their older ones which dates back to the early 2000's on my supra and so far so good. I've heard alot of members with the new PI converter are blowing them out really quick on supras with more than 500rwhp. So Titan motorsport has available their own brand which is billet and takes alot of abuse. If you plan on ever rebuilding your PI tq. converter, give Midwest Tq. converter a call and they can rebuild it with stronger sprags for roughly $300.

tomtnc

Yes, I installed a stand-alone transmission cooler with the PI converter. To note, the marginally increased stall speed on the PI converter really wasn't really enough to warrant it, but I did it just to be on the safe side.

Off the line, there I really can't feel much difference in the "but-o-meter". Yes, the engine definitely has a different tone as the RPM's are a little different. Either way, whatever marginal gain was had certainly wasn't worth the drivetrain problems, slipping (could be related to hitting rev-limiter issue) on the 1-2 transmission shift, and CEL.

I'm not one to spray down aftermarket parts, but when they fail, they earned it.

tomtnc

Thanks for the great info, nice to hear from you again. I chucked the PI converter as I am not interested in modifying my car any further. Love it just the way it is and realized long ago it's just not going to be what I want it to be throwing serious money and time at it, which I have lost all desire to do. You guys will have to email me when there are local events coming up. Somebody at my office building in Cornelius has a silver GS430 with a full body kit and five star aftermarket chrome wheels - need to figure out if they are on here.

tom steele

so what are you doing with the pi tourqe converter want to sell it cheap....

Rock-a-Lex

iTrader: (4)

Just out of curiousity what was your stall speed set to on your PI torque converter? I believe stock is set at 1800 rpm...I had mine done at 2900/3000 rpms. It is recommended that our cars respond well to a 2800-3200rpm range.

DumpedGS

iTrader: (1)

this is the reason i like re-stalled OEM converters. OEM parts, OEM reliability.

3UZFTE

OP, I know your happy with the stock converter, so this is mostly for others... If you guys really want this mod, try calling up your local tranny shops and see what they can do. As someone else mentioned in here, most shops can build a TC for your specific needs. Its been two years since I did the pricing, but I want to say a shop about 10 minutes away from me in Bloomington, MN would've built a spare one for me for somewhere under $500, now this was a just a ballpark, but you can get a better idea once you start asking questions. I am not sure if it's any cheaper then PI, but to know that it has a warranty and you can take it back if there are any issues is pretty nice. I would imagine if you had your own spare TC laying around, it would be far less. Just a little info.

tom steele

lextreme has them for i think 350 plus shipping and core they weld to reinforce them and change your stall for you i have been thinking of this route. also i have heard if you get those pi tourqe coverters rebuilt with better clutch packs but has been awhile since i seen that though... not sure on the price above it been awhile since i have been on lextremes site. seems like a real cool guy though he is a member here check his site out..

tom steele

i was wrong lextreme has them for 300 plus 40 shipping and 150 core charge pretty good deal but i want a manual trans so i dont want to put any more money into my current set up..

macd7919

iTrader: (10)

Restalled OEM Converters aren't stock and are no where near OEM reliability under hard use (i.e.- the reason you buy a higher stall, to get better launches).

They alter the speed by bending the fins in the converter to provide higher lockup. Any time you bend something from it's original form it weakens it. There is a reason you can't buy a restalled converter with a high stall such as 3800 rpm (which is what 95% of street supra's run, just using that application as an example), it's because the fins lose their integrity and are prone to fail due to the large deformation required to raise the stall speed that high. That's why companies such as Precision manufacture stalls which are designed to be used with a high stall speed.

I'm not here to agree or disagree with people opinions on Precision stalls but I think it's important to take the facts into account.

OP stated he had the stall in his car for 50,000 daily driven miles. In aftermarket performance applications that is quite awhile on a moving part, not to mention the fact that higher stall speeds greatly increase trans fluid temps, especially daily driving in traffic, stop and go etc.... Things that could contribute to the failure could be size/location of the trans cooler, frequency of fluid changes (you should change the fluid much more frequently with a higher stall) and the type of driving.

Again, I'm not saying the OP is at fault, it very well could have just been time for the stall to go but I think it's a little bit much to down a company which provided a part that operates under those conditions and lasted you 50,000 miles.

Rock-a-Lex

iTrader: (4)

^ Very well said!!!

tomtnc

I have to politely disagree with your assessment my friend. First, my car has very easy miles on it; never once has it seen a drag strip and only twice was the car run hard and long enough (that's what she said) to elevate transmission temperatures to a point where they could be an issue (Tail of the Dragon runs). Second, the transmission cooler was installed properly in front of the A/C condenser where it picks up maximum air flow from the nose of the car for maximum heat exchange. Third, the transmission has always had Amsoil synthetic compatible lubricant changed every 10-15K which is overkill. Fourth, I believe the stall speed was the standard 2800 spec model for our cars; this would certainly not put it in the realm of a "highly" modified converter. Given the easy miles and servicing record, there is no reason this converter shouldn't have lasted much longer. Certainly, not for the money I paid for it. Regardless of your opinion of PI quality, it's important we share these types of stories with each other. I wish I had seen a story like this from a reputable member before I bought the converter. Maybe this will save a young kid starting out some hard earned money and frustration.