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420-450bhp on wrx gearbox too much??
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Old 15 Jul 2012, 04:42 PM   #1 (permalink)
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Exclamation 420-450bhp on wrx gearbox too much??

Hi to all,
I own a 2005(54 plate) Subaru wrx, it is at the moment in bits as i am going to have the engine rebuilt and remapped up to 420-450bhp. The question is at this much power will the gearbox break?? If so does anyone know the max HP they are capable of??

If the gearbox will need replacing what are the best gearboxes that you would recommend. Sorry for the list of questions as im new to Scoobys.

*Also, is the stock internals, pistons, etc too weak to hold this much power??

Many regards,
ScoobyWorks

Last edited by scoobyworks; 16 Jul 2012 at 09:51 AM.
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Old 15 Jul 2012, 05:33 PM   #2 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

you'll be lucky fella...

6 speed conversion,quaif rebuild,strightcut rebuild will be your options for that power bracket..must admit i do know of a few rally scoobs in that pwer bracket running Forester XT gearboxes tranny code :- TY755VN2AA will need dif to match if you go that route..
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Old 12 Aug 2012, 06:35 PM   #3 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

*Also, is the stock internals, pistons, etc too weak to hold this much power??
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Old 12 Aug 2012, 09:25 PM   #4 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

As mentioned 6 speed is the way, especially with the amount of sti`s being broke and not sold as a car.
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Old 13 Aug 2012, 07:52 AM   #5 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

You will need forged internals for over 400 IMO
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Old 13 Aug 2012, 07:55 AM   #6 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

easier to buy a sti
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Old 13 Aug 2012, 09:03 AM   #7 (permalink)
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Exclamation Re: 420-450bhp on wrx gearbox too much??

Quote:
Originally Posted by bugeye_bob View Post
easier to buy a sti
I know,

As i have said in my previous threads...my mate had this scooby just parked at his garage covered in dust and the thing was I only went there for an exhaust to put on my bugeye but brought another scooby instead.

The cam belts had exploded so there was not a top half of the engine. I could of brought a STI but for 2300 you cant really argue (bearing in mind it had only did 50,000miles.) I saw a lot of potential within it. Also, for the price he was charging for a rebuild compared to other garages scoobyclinic,etc you couldn't say no

It's a project car and will be in excess of 450bhp...used on road and maybe track (depends if I like it or not.)

I read on other forums that's it not necessarily how much HP the gearbox can handle but how you maintain it.

Thanks for the help guys, I'm just looking out for members that have had experience of 420BHP++ on a WRX gearbox and feel free to tell me how it feels and what you shouldn't do,etc.

Many thanks,
ScoobyWorks
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Old 13 Aug 2012, 09:08 AM   #8 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

As said above, you'll need a six speed to take that. Otherwise you will strip the teeth gears at some stage
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Old 13 Aug 2012, 11:55 AM   #9 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

personaly i hate the 6 speed ratios, drive my dads alot and always glad when i get back in mine.
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Old 13 Aug 2012, 05:02 PM   #10 (permalink)
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Exclamation Re: 420-450bhp on wrx gearbox too much??

Quote:
Originally Posted by Tidgy View Post
personaly i hate the 6 speed ratios, drive my dads alot and always glad when i get back in mine.
I was asking from a WRX 5 speed point of view with this sort of power, but thanks anyway.

Scoobyworks
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Old 13 Aug 2012, 05:10 PM   #11 (permalink)
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Exclamation Re: 420-450bhp on wrx gearbox too much??

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Originally Posted by shambles View Post
As said above, you'll need a six speed to take that. Otherwise you will strip the teeth gears at some stage
Will it just be the gearbox that i will need or anything else(diffs,etc). How much is a 6 speed gearbox..anything to look out for when buying USED.

ScoobyWorks.
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Old 15 Aug 2012, 06:50 PM   #12 (permalink)
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Re: 420-450bhp on wrx gearbox too much??

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Originally Posted by scoobyworks View Post
I was asking from a WRX 5 speed point of view with this sort of power, but thanks anyway.

Scoobyworks

sorry yeah, i was talking about if you replaced it with a 6 speeder lol
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Old 26 Aug 2012, 08:58 PM   #13 (permalink)
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Exclamation Re: 420-450bhp on wrx gearbox too much??

Thanks for the help guys, I'm just looking out for members that have had experience of 420BHP++ on a WRX gearbox and feel free to tell me how it feels and what you shouldn't do,etc.
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