Ive owned Circle-D and PI converters that have both gone south... I've had two different Yanks in two different setups, and I have loved both of them. As far as locking up the converter at WOT, yeah, it'll get you a tenth or two and some mph, but I'd personally rather keep the longevity of a converter clutch, than get those two extra tenths. I keep mine unlocked the entire pass, I only use lockup for cruise.... people do it different ways. Ive got a SC3000 in my 4L80E

 

what happend to the PI? just the clutch? i am runing one in my truck putting 900+ through it with no issues..but i better nock on some wood after hearing your story..lol

 

I have had my trans out PLENTY ..... I run a very large rear mount truck.... I have spent more on trans and converters in 2 years then i did on the motor !!!.... My Truck has a Circle D in it ......

 

slightly different question but i've seen a few guys running upwards of 4000 stall on a frontmount turbo. Don't you want a lower stall to build boost quicker?

 

i had no luck with my pi in my 4l80e it fried it so now i got a new one but have not installed it yet, this one is built stronger this time or at least that what the told me. i'm thinking of probably going with circle d if the pi cant handle the power.