This question I know has come up several times but with No concrete answer. I'm looking at getting a Turbo kit. Yes I'm auto blah blah. I want to know who here is an auto Turbo what kind of numbers you are putting down. How long you have been putting said numbers down and if your trans has any upgrades. I'm basically trying to see what Max I can run safely without slushing my tranny will a valve body upgrade hold more. Torque convertor and what numbers are Max with these products. And does anyone know for sure what ipt s fully built will hold. Must be from experience please

 

i think from browsing around and reading that an auto can hold about 6psi 250 hp before the tranny starts to go

 

what about with valve body or full tranny work from ipt

 

I really don't agree with the 6psi and 250 assumption. I don't want to jinx myself, but I find myself at 8 psi, and running in high 13s in the 1/4 mi... I'm easily above 250 WHP. My tranny shifts clean and beautifully after going to the track over the last 2 months, and I push it very hard in the streets. I really hope I don't jinx myself... But as ScionFred and I were talking, I believe he was 260 - 275 and had no issues, and I'm running consistently faster in the 13s now... Probably at 290 WHP. Oh, this is an XB2 - I believe we have identical 4-spd transmissions. In addition, that's 8 PSI @ 11.9 - 12.1 A/F ratios with AC on... Turning AC off it gives me a leaner mixture, making more power. So on the track I'm definitely around 290. I don't think I could make the 1/4 in under 14 if I wasn't. (No weight reduction, no slicks, normal 93 pump gas).

 

I've been running 8psi for almost a year, no tranny upgrades besides a large b&m trans fluid cooler. No problems at all, still holds power, spins second, and doesnt slip and I hit full boost atleast once or twice everytime I drive

 

All i had was a trans cooler, and flushed the case every 10k miles with the OEM ATF. I made a little over 300whp just fine for about 30k miles, 60k total miles. When i would get on it, i would use the "L, 2, 3" function and let off when shifting. that worked for me just fine. the motor blew before the trans did.

 

I would not reccomend letting off when shifting, I believe that stalls the lubrication of the transmission, which it needs when it shifts. I could be wrong. Also, if your engine blew before the transmission did, then your tune was off. That's very odd. You must have been running super lean. Stick with your automatic transmission deciding when you shift, not you. It knows better and it will actually adjust to your driving and fuel consumptions.

 

A transmission cooler is mandatory. I have the DECENDENT kit, they supplied me with a transmission cooler when I purchased the 'moto radiator. I agree with this. Honestly, as I said above, it's all in your tuning. A bad tune, regardless of the PSI or HP, will ruin components in your transmission and engine. To the OP, you will be safe running 8PSI instead of 6PSI. To get the same performance out of 6PSI, you would have to run considerably leaner... if you run 8PSI, you can richen your mixture a little more, making it safer.

 

my motor didnt fail from running lean. i had a flawless tune from Performance Autowerks. it blew from a drop in oil pressure which destroyed my bearings. Beside the point, i had a trans temp gauge as well, and from what i noticed, it got a lot hotter if i just pulled through the gears and let it shift on its own, and stayed significantly cooler when i let off. also, when i didn't let off, it would slip. i did lots of trial and error to prevent trans damage, and that was the best combo i came up with. and for over 300whp for a LOT of miles, the proof shows that it worked quite well. hey i might have had a freak trans lol, idk. but i did lots of research before hand, cause i was always told that it will grenade at 300whp eventually. another variable could have been my torque curve, due to my small turbo (big 16g).

 

I do agree that letting the car shift on its own is the most proper thing to do. i usually don't recommend that (shifting manually) to people considering ive only owned 1 auto trans, and this was the only application i did it on under certain circumstances. but sometimes it slips out lol.

 

https://www.scionlife.com/forums/sho...d.php?t=126361

^^ Auto Transmission Build Up Guide


Also... look at the xB2 section. There is a guy running his xb2 transmission (u241e) built by level ten and the transmission is good for 500 whp.