20 replies to this topic

[inim_repooc]

you always hear about how the 998's happily rev all day long at this sort of rpm, but what about the 1275? I mean I often feel a bit like I'm going to end it killing it prematurely if I cruise at 70mph @4000 to long! what rpm and speed do you guys sit at for motorways?

[Spider]

When I go away on the bigger trip (at least one a year), we all sit at around 4000 RPM for weeks on end (our trips are usually around 10 000 km).

 

These engines are fine with revs.

[Cooperman]

It was always meant to rev.

The original 1071 Cooper 'S' had a 3.76:1 FDR and that gave 5000 rpm at 70 mph. We cruised above that all day long on a journey. The original Mk.1 1275 'S' had a 3.44 which gave 4200 rpm at 70 mph. I used to cruise mine at 80 to 85 (legal back then!) all the time which was around 5000 rpm.

It should not be a problem.

[jaydee]

Late engines have the webbing and a more accurate balance, making it stronger and reliable, ideally you can cruise at 4k rpm all day

You just need a decent oil to keep up with such long stress. Or even an oil cooler if you plan to use it a lot on motorways.

[racingbob]

I think the noise minis make particulary when stage 1 kits fitted etc

 

exhaust and pancake air filters make it sound worse

 

mine included

[Spider]

Most of the 'noise' comes from the fan!

[spiguy]

I actually find mine is happier sounding at 70 mph (just over 4000 RPM). It 'smooths out' a bit there. 3000RPM is much more boomy and noisy. I have certainly sat at 70 for a good couple of hours continuously on several occasions, and the car has been perfectly happy. In fact I tend to find that after a good long run at this sort of speed, the engine drives lovely once you slow down and come back on to twisty A roads. Not sure why!

[Pitcrew6464]

I race a standard 1275 up to 6500 through the gears no problems as of yet but cranks are the weak point 🙈

[mab01uk]

I think the noise minis make particulary when stage 1 kits fitted etc

 

exhaust and pancake air filters make it sound worse

 

mine included

 

I agree.....because many of us have become used to modern more refined cars with lots of clever soundproofing and 5th and 6th gears which help keep noise levels subdued, a classic Mini can sound like a it is under great stress at higher revs. When rebuilding a 1275 engine with its longer stroke it was always considered a good idea to have the engine, crankshaft, etc balanced during any machining operations which can make things a little smoother when revs are required.

Edited by mab01uk, 10 November 2015 - 12:48 PM.

[Cooperman]

Always remember a Mini is a 57-year-old design and you need to compare the cruising revs with its contemporaries. A 997 or 1200 Ford Anglia also used to cruise at around 4000 to 4500 rpm all the time, as did the Vauxhall Viva HA.

Then again, it was not unusual to have to fit a recon engine at 50,000 miles, or do a re-bore.

Modern cars are just engineered differently, to closer manufacturing tolerances and with higher low-end torque and higher overall gearing. But you can't make a classic car like a modern car, even if you wanted to. That is part of the fun of classic car owning and driving - the retro driving experience which includes cruising at high revs.

[adam_93rio]

Why wouldn't it be happy doing that? It's a car, made to be driven.
Mine has no back box's and the noise has never bothered me

[racingbob]

mines noisier at 3300 to 3600 some sort of resinance going on with the exhaust

 

then smoothes out

[Cooperman]

Why wouldn't it be happy doing that? It's a car, made to be driven.
Mine has no back box's and the noise has never bothered me

Quite right too. You don't buy a classic Mini for a smooth and quiet driving experience  . Give it some stick!

[Mini Manannán]

When I first got back into minis I was a bit nervous about revving it (partly due to not knowing the exact condition of the engine I had).  Now it's been rebuilt I find it and me happiest at 4k and above

[jakepalmerd13]

Since max torque in my 1275 is about 3k ish i tend to sit here witch is about 60 ish with a 3.1 FD