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Old Dec 18, 2003 | 04:48 PM
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Right well I am going for a strengthened gearbox. Been offered one with RA Ratios and a swap or my 1995 WRX Rear diff for a 3.54 to stretch the gearing a bit so its not so close. Also replacing the RA 5th with my 5th gear.

Will this make the gearing nicely spaced if you see what I mean (Not too technical) bar the 5th which will have a bit of a jump, or still be very very close.

Thanks.
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Old Dec 18, 2003 | 05:12 PM
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From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
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should be ok IMHO.

David
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Old Dec 18, 2003 | 08:26 PM
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Is the RA one any stronger????

I would speak/email ChristianR in Jersey, as he has a 2.5 TYPE R and may have another opinion. (Not that Dave's is not valid!).
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Old Dec 18, 2003 | 09:10 PM
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From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
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christian has a lateral syncro kit.
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Old Dec 19, 2003 | 11:07 AM
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The RA box I am looking at is ALOT stronger.

Any idea how much a WRX box with around 12000 miles on and quickshift is worth?

Sounds best option for me.

Cheers!
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Old Dec 19, 2003 | 11:53 AM
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uk 5th will be too tall.

0.825 wrx/sti 5th will be more like it.

The RA box will need 3.9 diffs front and rear, don't bother if you can't sort the diffs.

Paul
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Old Dec 22, 2003 | 08:19 AM
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Yep WRX 5th gear.

3.9 diffs are no problem. Maybe even dropping to 3.54...
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Old Dec 22, 2003 | 08:24 AM
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you can find a 3.545 front CWP?

It has been pondered, no one I know has heard of one, yet.

Paul
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Old Dec 22, 2003 | 09:38 AM
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Yep found one!

Is it worth putting one in then?
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Old Dec 22, 2003 | 09:44 AM
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erm, perhaps!

I would make sure first, then pass the details onto John Banks and he may well be very grateful

Paul
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Old Dec 22, 2003 | 10:06 AM
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I was going to fit the diff and then test drive it and see how it goes. If it isnt right ill stick a 3.9 diff in.

Is John Banks after one? Soon as I have tried it ill let him know.
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Old Dec 22, 2003 | 04:04 PM
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From: Leeds - It was 562.4bhp@28psi on Optimax, How much closer to 600 with race fuel and a bigger turbo?
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if you have found a 3.545 front could you call me or mail me?

David
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Old Dec 22, 2003 | 04:21 PM
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YHM
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Old Dec 22, 2003 | 07:37 PM
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Question

Now I'm confused.
I thought the 'best' RA set-up is one with a 4.11 diff for max accelleration. I hope so as it's killing me putting it all in my StiV3 hill climber....
Comments??
Graham
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Old Dec 22, 2003 | 07:40 PM
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im sure the RA box that is going into my car is 3.9 diffs
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Old Dec 22, 2003 | 08:07 PM
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Depends which RA box you get. The original RAs had very short ratios and relied on 3.9 diffs, as they are stronger (in theory).

Later RAs use 4.44 diffs and ratios that are not nearly as short.

The Hewland S2 gearkit uses the original ratios and requires a 3.9 final dive giving about 120mph at 7000 in 5th.

Paul
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Old Dec 23, 2003 | 01:23 PM
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So you replace the 5th gear with a WRX one and in theory with a 3.9 diff you can get a higher top speed.

And if you put a 3.54 diff in this increases even more then?

Just trying to get my head aroudn it.
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Old Dec 23, 2003 | 01:59 PM
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yes, basically.

I don't have ratios to hand, but they are out there, and I can add some mph/1000rpm data.

paul
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Old Dec 23, 2003 | 02:27 PM
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Marvellous!
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Old Dec 26, 2003 | 08:08 PM
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Cool

Any of you guys got a spare rear diff pinion flange and nut for my RA diff? I CANNOT get the parts off my STi diff, so I need some loose parts. Any offers/advice/condolences?
Graham.
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