changing diff ratios
12 November 2014, 06:51 PM
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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?
12 November 2014, 06:54 PM
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12 November 2014, 06:56 PM
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I think you may have to swap the front diff too.
12 November 2014, 08:14 PM
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yes will be changing both diffs.
12 November 2014, 08:20 PM
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Quote:
Originally Posted by
Infected by sti
Higher
Erm no! 4.11 to 4.44 will be lower top speed
12 November 2014, 08:30 PM
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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; 12 November 2014 at 08:31 PM .
12 November 2014, 08:31 PM
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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
12 November 2014, 08:33 PM
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what do I know, I was basing it on my type r 3.9 diff, truth is I aint got a clue.
12 November 2014, 08:35 PM
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Look at it like this (assuming fourth is direct)
12 November 2014, 08:37 PM
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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......
12 November 2014, 09:01 PM
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Quote:
Originally Posted by
boosted
Look at it like this (assuming fourth is direct)
Ok I get it now, learn something new everyday.
13 November 2014, 12:10 AM
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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
13 November 2014, 12:20 AM
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Type r is ish 4k at 70 and they do take off.
13 November 2014, 08:32 AM
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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
13 November 2014, 08:42 AM
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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.
13 November 2014, 08:51 AM
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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
13 November 2014, 08:56 AM
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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
13 November 2014, 08:57 AM
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cheers banny.
13 November 2014, 09:07 PM
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How to break the 155mph top end with a 5 speed box?
14 November 2014, 06:30 AM
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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
14 November 2014, 08:50 AM
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Hmm, I wonder what's in my UK classic then. 3.9?
14 November 2014, 09:03 AM
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Quote:
Originally Posted by
piehole1983
Hmm, I wonder what's in my UK classic then. 3.9?
Gearbox code?
14 November 2014, 09:06 AM
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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?
14 November 2014, 09:38 AM
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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
14 November 2014, 09:47 AM
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14 November 2014, 11:04 AM
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Quote:
Originally Posted by
scottydouk
yes will be changing both diffs.
And pinion shaft
16 November 2014, 06:20 PM
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mine is currently 100mph at 4,000 rpm with 4.111 diff and p1 5th gear set up
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12 November 2014, 08:30 PM
Ok I get it now, learn something new everyday.
