Volvo 850 T-5 Auto 300bhp+ why not

[charly001]

I have just got a 97 Volvo T-5 CD Auto and after extensive research I have not found an answer to a question regarding BHP. Why is 300 bhp a limit for the automatic gearbox? Seems there is no definate answer so far only one person has come close to a good answer about the box slipping until the fluid has cooled back. I have an Aston Martin DB9 with auto transmission running in excess of 500 bhp that box doesnt slip so why does the T-5 box get upset with higher powers?

Charlotte

 

[pgarner]

not sure i know 300bhp was supposed to be seen as a limit for the engine as the cylinder liners werent up to the job

 

[claymore]

I think you should be fine as long as you have a good oil cooler, make sure you don't use a manual boost controller as thet would bring the boost in to hard, also you would be better off with either an upsolute or mte map which have a nice linear boost curve as opposed to the rica which is bit more aggresive in lower revs ( but on a manual feels more fun) IMO

 

[claymore]

not sure i know 300bhp was supposed to be seen as a limit for the engine as the cylinder liners werent up to the job

conrods bend at about 340 bhp, but the OP was quering the auto box I think, not the engine.

 

[pgarner]

cheers for the info. i knew she was asking about the auto box but it was all i could think off at the time.

 

[charly001]

I think you should be fine as long as you have a good oil cooler, make sure you don't use a manual boost controller as thet would bring the boost in to hard, also you would be better off with either an upsolute or mte map which have a nice linear boost curve as opposed to the rica which is bit more aggresive in lower revs ( but on a manual feels more fun) IMO

Thanks for both sets of info. I don't intend on taking the engine too far I know most remaps will only give 15-30% increase in reality unlike the figures quoted taken from a really good map event and not the norm. I might think about rebuilding the engine after a while as the car has around 230,000 not that high a touch too high to do really hard mods. I will be fitting an external cooler as matter of course as I tow a lot

Continue with the replies please I need all the information I can gather and just to add to the melting pot I've spoken to a reputable Auto transmission specialist in Norfolk who is saying as long as the boost isn't brought in too hard then any realistic BHP shouldnt be an issue.

Charlotte

 

[obi_waynne]

These have torque converters (a pretty strong GM derived Aisin Warner box IIRC?) so I don't really see a problem with so much power on an auto box. The CV joints/diff would potentially be the weak area to my mind.

You just know it's going to cost you a fortune in Tyres? (Welcome to TorqueCars, nice to have you with us!)

 

[charly001]

These have torque converters (a pretty strong GM derived Aisin Warner box IIRC?) so I don't really see a problem with so much power on an auto box. The CV joints/diff would potentially be the weak area to my mind.

You just know it's going to cost you a fortune in Tyres? (Welcome to TorqueCars, nice to have you with us!)

Not as much as my AML DB9S on Pirelli P Zero

 

[obi_waynne]

You have a heavy right foot then.

Why did you get rid of the DB9? What were the running costs like?

 

[charly001]

You have a heavy right foot then.

Why did you get rid of the DB9? What were the running costs like?

I haven't got rid of the DB9 Running costs for a service you could buy a brilliant state R to give you some idea the last basic service I had cost £1600 a full service is £2000-3500 depends what you want doing, fuel economy low 20's if I boot it I can get to single figures [I boot it]