MileHIFcar

The Asin/Lexus AA80E transmission from what I saw on another thread is only rated for 405 Ft-lbs of torque

If that's true what's going to happen long term to the S/C kit customers let alone guys who have been running NOS long term

I don't know the longevity/durability of our 8 speed transmission when TQ is increased like it's about to see with the S/C kit (forced induction) and tuning ability now that the ECU protocols have been released?

I'm assuming that TQ figures are going to jump to about 500 Ft-lbs of TQ with the S/C kit, Rohi123 that dynoed with us a couple weeks ago with a 100 shot of NOS hit 474 TQ & 501 @ the wheels!......I think this needs to be discussed now that forced induction is going to be a reality on our cars here in the near future. We will now start to realize which parts of the ISF chassis/motor/drivetrain etc..... will be able to handle the stress of forced induction over the long haul?

I know the other guys who contributed on the other thread about this subject will chime in with a link supporting the 405 Ft-lbs of TQ that our transmission is rated for......

F_Throttle

I know my past auto cars required a transmission upgrade kit, when boosting. 'Level 10' was a name that went along with most builds i've seen. And for those that did boost and upgrade the tranny, they had to stick to manual mode when loading.

I'd like to hear from others about what the transmission can handle. Also, I believe our car comes with a trans cooler.

MileHIFcar

I don't know but it'll be interesting to see what Rafi has to say about the transmission capabilities and long term outlook with the S/C kit that he is developing?? Hopefully he chimes in on this thread soon to answer some questions....

Fsport2UR

The 405 figure is more likely the manufactures max 'recommended' torque rating, as in they won't guarantee or warranty anything if a car manufacture like Toyota wants to toss the tranny in something that has excessive torque. 405 can also mean the max reliability rating, anything over that and longevity goes down.
This discussion will end up like the Supra V160 Getrag tranny debate in the 90s. As Lance pointed out, it was rated below the ISF AA80E tranny, but after years of Supra owners beating on it with 800-1000hp, everyone found out that max rated figure to be obviously incorrect. The only way to figure out how much the ISF tranny can take, is to have modified ISFs of different power and torque levels beat on it until it dies.

xSumDumGuy

Here is the link again. Someone posted it up on the other thread as well. As it was already mentioned, we'll have to wait and see once we have people pushing well over 405 ft-lbs constantly.

http://documents.epfl.ch/users/f/fr/...oyotaAA80E.pdf

sw2oboi

iTrader: (12)

Also depends on how aggressive the torque curve is.

juanmedina

The RC-F makes 389lb-ft as an engineering that is really close for comfort if the transmission is really rated to 405lb-ft max. You have to remember that the transmission probably has a big safety factor. I would not worry about it yet, there is ways to keep and engine or transmission together from high torque. The GTR and subaru guys keep the torque down with the tune to keep their transmission from breaking and rods for flying through the block.

NotnFsport

iTrader: (10)

Heres a 2010 and its well above 405 ft lbs of torque

F_Throttle

How is the rating determined? Is it done on continuous loads?

The monster supras aren't on full load 100% of the time. I believe the drag-purposed Supras are using aftermarket gears.

MileHIFcar

I would assume that RR-Racing is going to limit boost in 1st and 2nd gears in the tune and then release the full amount in 3rd through 8th to prevent overloading the transmission and for traction issues (just my guess at this point)?

ISFpat

iTrader: (10)

Its not just the "transmission model" that determines what torque it can handle.. theres other factors such as cooling and weak points that might need to be addressed. I mentioned before that the current ISF gearing is not suited for boost, your first and second gears are already becoming an issue with bolt ons.. so any form of boost is going to render those gears useless.

Unfortunately I believe there isn't even new gears or aftermarket clutches thats available to help support the added power unlike in most other vehicles.

The ISF is not and will always not be a proper tuner car for those reasons. Know the limitations and appreciate what it has to offer.. in this case it is reliability that no other car in its class can match.

Max16

full torque is available through all gears specially higher gears since you have traction
The only reason to do that would be for traction purposes.

Fsport2UR

An aftermarket traction control system helped address "the useless 1st and 2nd gears" in Supras that have +1000hp. Same can be done in an ISF. Which also would help keep from beating on the tranny. As well as tuning, which you can back off power on 1st and 2nd gear if need be.

tas02

iTrader: (2)

So few have failed to date, none in race situations AFIK. Concern seems pointless at this stage.

ISFpat

iTrader: (10)

So you want to create this "aftermarket traction control system" to an already difficult to tune platform? Comparing a 90's car with minimal electronics and ecu intervention to a vehicle that took almost 10 years to crack the ECU is not the same by any means.

Backing off power in 1st and 2nd? So your 1/4 is going to be severely hindered and your car will pretty much only good for roll races.. and we all know how fun that is on the street, where most of these cars spend their time.