23 replies to this topic

[happydude2012]

final drive questions.

 

i currently have 3:44 ( i believe)

 

a few people have said

 

1) Nah mate, you want a 3:1....longer legs on the A roads and motorways and you wont feel like your out of gears at 70-80mph

 

2) Mah mate! you want a 3:2, best of both worlds. long legs but wont lose out too much on acceleration.

 

3) Whats wrong with 3:4?

 

there were some drives ive never heard of mentioned.... 

 

so really...i commute, mostly B and A roads....why would i change from my current final drive?

[nicklouse]

i would not. put the money elsewhere unless you have a damaged one.

[Cooperman]

The 3.44 is, IMHO, the ideal compromise for a mixed-use classic Mini. 

In fact, it is the FDR as originally fitted to the Mk.1 1275 Cooper 'S'.

You can cruise a Mini at 4000 rpm all day long and with a 3.44:1 that is about 65 mph in top gear.

[Bat]

Hi,

The taller you go, that's a smaller number eg 3.1, the more torque from the engine you'll need to make it accelerate.

Cheers 

[Icey]

The 3.44 is, IMHO, the ideal compromise for a mixed-use classic Mini. 

In fact, it is the FDR as originally fitted to the Mk.1 1275 Cooper 'S'.

You can cruise a Mini at 4000 rpm all day long and with a 3.44:1 that is about 65 mph in top gear.

 

This is what we have and I completely agree. Yeah, it might be nice spinning a little slower on the motorway but I wouldn't want to loose the acceleration everywhere else.

 

The only place I've found it a limitation is on start-finish straight around Castle Combe (folly/avon rise) where I'm running right up to 5.5-6k RPM before the next corner but that only happens a couple of times a year!

[Dusky]

You ll feel out of gears at 80. Then again, most minis wont go much faster anyway. (Inb4stage1-998'swith110mphtopspeed)

[Cooperman]

I did have a 1990 Cooper into which I fitted a 3.44:1 FDR and 'blueprinted' the engine with a few tweaks to give just over 80 bhp at the flywheel at 5700 rpm.

 

I cruised it at up to 4500 rpm on main roads/motorways and used up to 6400 rpm when driving in competition. It was really excellent and I wouldn't have wanted a higher FDR.

 

My Cooper 'S' rally car has a 3.9:1 FDR, but max power is at 6400 rpm. On rally road sections I will cruise at up to 5000 rpm which is about 70 mph in 4th.

 

Don't be afraid to rev an old classic Mini. All old classics used to rev higher than modern cars at normal cruise speeds.

[Bat]

Hi,

The taller FDs work best with high torque engines such as 1380s or boosted engines.

Cheers 

[Ethel]

When they were fitting 3.44's they were only concerned with matching the engine's performance to give the best performance to the car. The later, lower ratio, gears were for better mpg and less noise.

[Midas Mk1]

Had 2.7,3.1,3.2,.3.44, 3.6, 3.7,3.9

 

With a 90-100bhp motor 3.1, 3.2 is perfect. Guess what ratios I have in my Minis? Means cruising at 85 is pleasurable long distance.and also nailing it though the gears top of third is fast..

Edited by Midas Mk1, 31 August 2018 - 08:45 AM.

[alex-95]

I've been having this dilemma at the minute, I've only ever driven 998's with 2.9 ratio diffs. I can't make up my mind between 3.2 and 3.44, but swaying more towards the 3.2 mainly because living in Cornwall all the shows are a long journey away but also would still have a bit of go on the twisty lanes.

[Sprocket]

Had 2.7,3.1,3.2,.3.44, 3.6, 3.7,3.9

With a 90-100bhp motor 3.1, 3.2 is perfect. Guess what ratios I have in my Minis? Means cruising at 85 is pleasurable long distance.and also nailing it though the gears top of third is fast..

It’s not really the power of an engine you need to consider, it’s the torque, it matters where the torque is in the Rev range too.

[SolarB]

Fitted a 2.9 with the MG Metro lump.

Have now gone back to a 3.44.

Much better.

[Cooperman]

To my mind, we own classic cars, of whatever type you may choose, to enjoy retro-motoring as it used to be. You don't buy a classic to make it more like a modern car.

The original 850, 997 and 998 cars had a 3.76:1 FDR, as did the 1071 and 970 'S' models. The 1275 'S' had the higher 3.44:1 FDR. They all went well and we used to use them as everyday cars, not as pampered classics, and do thousands of miles per year. Those low (by today's standards) were fine for the characteristics of the A-Series engine which had maximum torque rather higher up the rev range than today's more flexible engines.

Personally I love the 3.44 in a big engine and it can be good in a 998 with a fairly standard camshaft.

Enjoy classic motoring as it used to be (when I were a lad!!!).

Edited by Cooperman, 31 August 2018 - 06:49 PM.

[Magneto]

These cars are noisy enough without having the engine all wound out......however, horses for courses........here in the middle of the US where I live it's a long journey (600 miles one way to Denver, 500 miles to Dallas for example) to any of the shows or meets and our highway speed limit is 75 mph or higher, so having the reduced revs really quiets the car down and makes those long trips more palatable. If I'm just going to something less than 3 hours away the 3:44 is fine. For a big motor the taller ratios work fine, and I think the 3:1 is a perfect blend of good acceleration and quieter running with a well tuned 1275 or bigger. I haven't driven a 3:1 in a 998 but I expect once you get into hilly country you'd be spending a lot of time in 3rd.

Edited by Magneto, 31 August 2018 - 04:56 PM.