changing diff ratios
Nov 12, 2014 | 06:51 PM
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From: kent
changing diff ratios
On the 5 speed gearboxes, changing diff ratios from a 4.111 to a 4.444 will it give a higher or lower top speed?
Nov 12, 2014 | 06:54 PM
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From: Cardiff
Nov 12, 2014 | 06:56 PM
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From: Living the dream
I think you may have to swap the front diff too.
Nov 12, 2014 | 08:14 PM
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From: kent
yes will be changing both diffs.
Nov 12, 2014 | 08:20 PM
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From: harlow
Quote:
Originally Posted by
Infected by sti
Higher
Erm no! 4.11 to 4.44 will be lower top speed
Nov 12, 2014 | 08:30 PM
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From: Living the dream
I think Infected by STI might be right as the 3.9 rear diff is shorter with lower top speed, or is that to do with the gear ratios.
P.s it's still top speed of 155mph + so doubt you'll be using it too often.
Last edited by ditchmyster; Nov 12, 2014 at 08:31 PM .
Nov 12, 2014 | 08:31 PM
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From: harlow
Quote:
Originally Posted by
ditchmyster
I think Infected by STI might be right as the 3.9 rear diff is shorter with lower top speed, or is that to do with the gear ratios.
3.9 is "taller" than 4.11 I'm
Affraid
Nov 12, 2014 | 08:33 PM
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From: Living the dream
what do I know, I was basing it on my type r 3.9 diff, truth is I aint got a clue.
Nov 12, 2014 | 08:35 PM
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From: harlow
Look at it like this (assuming fourth is direct)
Nov 12, 2014 | 08:37 PM
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From: harlow
Quote:
Originally Posted by
ditchmyster
I think Infected by STI might be right as the 3.9 rear diff is shorter with lower top speed, or is that to do with the gear ratios.
P.s it's still top speed of 155mph + so doubt you'll be using it too often.
Sixth on my diesel audi box is geared for 233mph at 7250rpm! Ha just need another 1000hp to pull it......
Nov 12, 2014 | 09:01 PM
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From: Living the dream
Quote:
Originally Posted by
boosted
Look at it like this (assuming fourth is direct)
Ok I get it now, learn something new everyday.
Nov 13, 2014 | 12:10 AM
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From: Cardiff
Yea my bad, it's the gearing on the JDM boxes that's shorter which is why it has the taller final drive to compensate I guess or you be at 4k sat at 70mph
Bet it would take off tho
Nov 13, 2014 | 12:20 AM
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From: Living the dream
Type r is ish 4k at 70 and they do take off.
Nov 13, 2014 | 08:32 AM
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From: Type R
Quote:
Originally Posted by
ditchmyster
Type r is ish 4k at 70 and they do take off.
Type R is not 3.9 as standard it is a 4.444 ratio
Nov 13, 2014 | 08:42 AM
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From: Living the dream
Quote:
Originally Posted by
banny sti
Type R is not 3.9 as standard it is a 4.444 ratio
I need to book in to see a kwack, I think I might be suffering early onset alzheimers.
What has a 3.9 diff.
Nov 13, 2014 | 08:51 AM
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From: Type R
Quote:
Originally Posted by
ditchmyster
I need to book in to see a kwack, I think I might be suffering early onset alzheimers.
What has a 3.9 diff.
, 3.9 is fitted to the newage jdm sti
Nov 13, 2014 | 08:56 AM
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From: harlow
Quote:
Originally Posted by
ditchmyster
I need to book in to see a kwack, I think I might be suffering early onset alzheimers.
What has a 3.9 diff.
All uk gearboxes are 3.9, so all "VN" ratio gearboxes
Nov 13, 2014 | 08:57 AM
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From: Living the dream
cheers banny.
Nov 13, 2014 | 09:07 PM
Thread Starter
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From: kent
How to break the 155mph top end with a 5 speed box?
Nov 14, 2014 | 06:30 AM
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From: harlow
Quote:
Originally Posted by
scottydouk
How to break the 155mph top end with a 5 speed box?
Plenty of power and a high rev limit. 200mph is possible circa 7500 rpm on UK VN 3.9 ratios
Nov 14, 2014 | 08:50 AM
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From: Belfast
Hmm, I wonder what's in my UK classic then. 3.9?
Nov 14, 2014 | 09:03 AM
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From: harlow
Quote:
Originally Posted by
piehole1983
Hmm, I wonder what's in my UK classic then. 3.9?
Gearbox code?
Nov 14, 2014 | 09:06 AM
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From: Belfast
Quote:
Originally Posted by
boosted
Gearbox code?
Good question, I'll have to find out later. I know it's on the vin plate but is it easily accessible in the box itself?
Nov 14, 2014 | 09:38 AM
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From: harlow
Quote:
Originally Posted by
piehole1983
Good question, I'll have to find out later. I know it's on the vin plate but is it easily accessible in the box itself?
Yes, open the bonnet and look by starter
Nov 14, 2014 | 09:47 AM
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From: Belfast
Nov 14, 2014 | 11:04 AM
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From: harlow
Quote:
Originally Posted by
scottydouk
yes will be changing both diffs.
And pinion shaft
Nov 16, 2014 | 06:20 PM
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From: kent
mine is currently 100mph at 4,000 rpm with 4.111 diff and p1 5th gear set up
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Ok I get it now, learn something new everyday.
