Ausmini
It is currently Tue Jul 22, 2025 7:23 am

All times are UTC + 10 hours




Post new topic Reply to topic  [ 13 posts ] 
Author Message
 Post subject: Quick diff question.
PostPosted: Tue Dec 02, 2014 3:46 pm 
Offline
848cc
848cc

Joined: Mon Sep 30, 2013 7:32 pm
Posts: 109
Location: Ipswich
Sounding like a newbie, what's the pro's and con's of both 3.4 and 3.7 crown-wheels??

_________________
If it has tit's or tires....It'll take all your money!
74 Leyland Clubman S (scrap)
77 Leyland Clubman S


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Tue Dec 02, 2014 5:59 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39755
Location: near Baulkham Hills, NSW
3.44 is good for a road car, as long as the motor is a 1098 or bigger.
3.76 was fitted stock on 850, 997/998 Cooper and 998 Mini Deluxe, is also used in group Nb race cars. It's a bit busy for cruising with a big motor.

In between there is a 3.647, was fitted to most Mini K and 1100 Clubbies using the remote box.

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Tue Dec 02, 2014 6:36 pm 
Offline
848cc
848cc

Joined: Mon Sep 30, 2013 7:32 pm
Posts: 109
Location: Ipswich
So a 3.76 (22g401) is best for a standard 998?
If so it looks like I have a 22g411 to sell.

_________________
If it has tit's or tires....It'll take all your money!
74 Leyland Clubman S (scrap)
77 Leyland Clubman S


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Tue Dec 02, 2014 7:30 pm 
Offline
1275cc
1275cc
User avatar

Joined: Thu May 24, 2007 7:19 pm
Posts: 5370
Location: Yandina,Sunshine Coast,QLD
Basically the higher the number the more revs you'll be doing at 100km/h. Or to put it another way the faster you'll accelerate off the line.

_________________
Respect mine and I'll respect yours.


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Tue Dec 02, 2014 8:14 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39755
Location: near Baulkham Hills, NSW
74Club-man wrote:
So a 3.76 (22g401) is best for a standard 998?
If so it looks like I have a 22g411 to sell.


3.44 was used in most Mini rodchange boxes, including the 998 from 1975 on.
A 3.76 is better for going up hills with a 998 though. :wink:

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 6:36 am 
Offline
848cc
848cc

Joined: Mon Sep 30, 2013 7:32 pm
Posts: 109
Location: Ipswich
Thanks guys.

_________________
If it has tit's or tires....It'll take all your money!
74 Leyland Clubman S (scrap)
77 Leyland Clubman S


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 8:58 am 
Offline
998cc
998cc

Joined: Fri Apr 01, 2011 8:33 pm
Posts: 1195
Like Doc says... but consider carefully what you intend to do ... and where you live.

A 3.7 will blunt the acceleration edge and require an earlier downshift on hills.

The upside is a much more relaxed car if you spend any amount of time on the freeway/highway..

Cheers, Ian

Oh, and BTW, its not just the crown wheel involved in ratio change..


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 10:05 am 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39755
Location: near Baulkham Hills, NSW
1071 S wrote:
Like Doc says... but consider carefully what you intend to do ... and where you live.

A 3.7 will blunt the acceleration edge and require an earlier downshift on hills.

The upside is a much more relaxed car if you spend any amount of time on the freeway/highway..

Cheers, Ian

Oh, and BTW, its not just the crown wheel involved in ratio change..

Ian you got that statement arse about... :)

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 10:46 am 
Offline
1360cc
1360cc
User avatar

Joined: Sun Apr 11, 2004 11:32 am
Posts: 12390
Location: Sthrn HiLoLands, NSW, Australia
74Club-man wrote:
So a 3.76 (22g401) is best for a standard 998?
If so it looks like I have a 22g411 to sell.


Why? just tickle the engine a little so that it will pull the higher diff and enjoy the lower revs when cruising...(if that is your thing and the type of work the car does).

_________________
"Show me the Mini!"


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 11:37 am 
Offline
998cc
998cc

Joined: Fri Apr 01, 2011 8:33 pm
Posts: 1195
drmini in aust wrote:
1071 S wrote:
Like Doc says... but consider carefully what you intend to do ... and where you live.

A 3.7 will blunt the acceleration edge and require an earlier downshift on hills.

The upside is a much more relaxed car if you spend any amount of time on the freeway/highway..

Cheers, Ian

Oh, and BTW, its not just the crown wheel involved in ratio change..

Ian you got that statement arse about... :)


Not a big problem ...only the numbers are wrong.... and I got the three correct :oops:

But just to remove confusion.. I should have typed "3.44"

Cheers...


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 2:43 pm 
Offline
848cc
848cc

Joined: Mon Sep 30, 2013 7:32 pm
Posts: 109
Location: Ipswich
Ok so snap question, what is the best diff ratio for a stage one 998 to be used for shows and general Sunday cruising???

_________________
If it has tit's or tires....It'll take all your money!
74 Leyland Clubman S (scrap)
77 Leyland Clubman S


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 2:59 pm 
Offline
religious status
religious status
User avatar

Joined: Fri Mar 19, 2004 6:19 pm
Posts: 39755
Location: near Baulkham Hills, NSW
3.44 then. :)

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R. :mrgreen:


Top
 Profile  
 
 Post subject: Re: Quick diff question.
PostPosted: Wed Dec 03, 2014 6:05 pm 
Offline
848cc
848cc

Joined: Mon Sep 30, 2013 7:32 pm
Posts: 109
Location: Ipswich
Thanks drmini.

_________________
If it has tit's or tires....It'll take all your money!
74 Leyland Clubman S (scrap)
77 Leyland Clubman S


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 13 posts ] 

All times are UTC + 10 hours


Who is online

Users browsing this forum: No registered users and 89 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  

© 2016 Ausmini. All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.