PassionFord - Ford Focus, Escort & RS Forum Discussion

Notices
General Car Related Discussion. To discuss anything that is related to cars and automotive technology that doesnt naturally fit into another forum catagory.

diff ratio wheel size

Thread Tools
 
Search this Thread
 
Old Jan 16, 2012 | 06:22 PM
Share
  #1  
bly's Avatar
bly
Thread Starter
Wahay!! I've lost my Virginity!!
 
Joined: Jul 2009
Posts: 69
Likes: 0
From: poole
Default diff ratio wheel size
Can anyone help ,some of you might know i am in middle or at the begining of building impreza powerd Mk1 escort , i am going to be
useing a Sti v3 Type Ra engine and gearbox ,

they run a 4.44.1 diff ratio on 16inch wheels cams on v3 Type Ra
rev to 8400 rpm

i will be useing Atlas Axle with 8x13 wheels

does anyone know what diff ratio i will need with the smaller 13 inch wheels to get same ratio as ith 16inch

thanks
Reply
0
Old Jan 16, 2012 | 06:27 PM
Share
  #2  
Rod-Tarry's Avatar
Rod-Tarry
Happily retired
 
Joined: Nov 2006
Posts: 7,707
Likes: 238
From: Hampshire
Default
Wheels size means nothing need tyres size on both wheels. 5th gear ratio also required then its easy.
Reply
0
Old Jan 16, 2012 | 06:58 PM
Share
  #3  
bly's Avatar
bly
Thread Starter
Wahay!! I've lost my Virginity!!
 
Joined: Jul 2009
Posts: 69
Likes: 0
From: poole
Default
on gearbox chart 5th = 0.825
impreza wheels 205/50x16
escort wheels 215/50x13
Reply
0
Old Jan 16, 2012 | 07:10 PM
Share
  #4  
Rod-Tarry's Avatar
Rod-Tarry
Happily retired
 
Joined: Nov 2006
Posts: 7,707
Likes: 238
From: Hampshire
Default
The Imprezza would give 19.55mph/1000rpm in 5th so 8400rpm = 164.2mph.

To get exactly the same in the Escort would require a 3.96 diff or as close to that as possible.

Cheers Rod
Reply
0
Old Jan 16, 2012 | 07:58 PM
Share
  #5  
bly's Avatar
bly
Thread Starter
Wahay!! I've lost my Virginity!!
 
Joined: Jul 2009
Posts: 69
Likes: 0
From: poole
Default
ok thanks, 3.9 in atlas are hard to find was thinking 3.75 which are easey to find and mybe try to get a 40-45 x13 tyre
Reply
0
Old Jan 16, 2012 | 10:14 PM
Share
  #6  
stevieturbo's Avatar
stevieturbo
C**t
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Oct 2003
Posts: 7,998
Likes: 269
From: Norn Iron
Default
What sort of overall gearing do you want ?

Even on the Subaru with the 4.44, it is horrifically short gearing.
Reply
0
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Alloy suggestions for my ka
charlierothwell
Ford KA
2
Nov 5, 2015 06:56 PM
Extremely mint rwd focus cosworth shell
Focosmitch
Ford RS Cosworth Parts for Sale
5
Nov 3, 2015 04:08 PM
Best turbo for 450+
RSBryden
General Car Related Discussion.
6
Sep 6, 2015 08:39 PM
can anyone identify these wheels
andrewmctiernan
Wheels and Tyres
5
Sep 3, 2015 08:22 PM
15 inch Rs seven spoke alloys and tyres, like new, never refurbed
3dr cossie
Alloy wheels and ICE for sale
1
Sep 2, 2015 08:58 PM
Back to Subforum
General Car Related Discussion.
View Next Unread
Rebuilding CV's, what have i done wrong??




Advanced Search
Reply Closed Thread Share
Forum Jump

All times are GMT. The time now is 10:40 PM.