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i am relatively new to the Skyline scene but not new to blowing up gearboxes in turbo cars due to too much power.i am driving a 1994 gts-t with the rb25det engine,its an auto and as far as i know its standard.i am wanting to add some mods to what i currently have(full exhaust,hks pod filter,hks blow off valve and a turbo timer as far as im aware).how much power can the standard auto gearbox handle on a daily driver? also what kind of mods can be used to prolong the life of the gearbox? i am wanting to get up to around 400bhp at the flywheel and am checking out before i go and wreck the gearbox.

thanks in advance :(

Somewhere like Yarra Valley Autos or KEAS would be the places to talk to, very good in the business

All sorts of upgrades around i believe.

I dont think the stock auto will hold 400hp @ the fly to be honest. For a while maybe, but it will die so best get it done while you can.

speak to RCHOO (pm if you like)

he has blown two auto rb25det boxes

maybe he can shed some insight on the cause of failure

might be some helpful info too, he was getting one of them rebuilt too

i am wanting to add some mods to what i currently have(full exhaust,hks pod filter,hks blow off valve and a turbo timer as far as im aware)

Hmmmm.... The BOV and Turbo timer add eleventy billion rwkw!

stock box with a shift kit and trans cooler will handle up to 300rwkws for a while.

so if you only want around 230 rwkws, it should be fine, with just the shift kit and trans cooler.

if it starts flaring get MV autos to build you a custom box with high stall, which is what i have.

currrently running 320rwkws with 24 psi thru a gt3582r/iw daily driven.

I was told by MV also that the stock box will handle around 260rwkw in stock form, but mine with 235rwkw rides the 2nd gear band during the change for ages so a shift kit and tranny cooler are next on the list, and if I can afford it I will get the higher stall option aswell.

He said if I was going for more power then I would have to upgrade the box as it does not have enough clutch surface area in the box clutchpacks to hold onto much more power.

The 235rwkw I have roughly equates to 420hp odd at the flywheel.

Dave

I have gone through 3 autos before i finally had mine rebuilt

first 2 died with simply an rb25 pushing 250rwhp and they had oil coolers. boxes were a bit iffy though. I bought a good box though with only 40xxx kms and it lasted 2 days with 330rwhp and it had a KEAS full Manual kit. Now have my current box which has been rebuilt and it seems happy with 370 runnign through it. I was told the stock box should hold up to 350rwhp with a good oil cooler and shift kit, but i dont believe that lol.

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