41 replies to this topic

[Cooperman]

Wow, a thread revival after almost 12 years! Is that a record?

 

The achievable maximum speeds depend on so many factors.

The final drive is very important as if a high ratio final drive is used to give cruising at lower revs, then top speed may well be lower as the peak torque and peak power points will mean it may not pull through to top speed in top.

 

Then there are the various drag-increasing items which may or may not be present.

If maximum speed is important, then remove the huge external rear view mirrors and just have a small bullet shaped on on the driver's door. Remove the wheel arch extensions and run with narrow wheels and 145 section tyres (that may also improve the handling). and fit a flat tray under the rear sub-frame. Just doing that could easily put 5 mph or more on the maximum speed. A 3.44:1 FDR is also god on a 1275 and a 3.76:1 on a 998 or 850. Yes, it will rev, but it will then pull max. speed at somewhere near peak revs.

 

But even doing all that, a Mini will still be a slow, old classic car, but will give a lot of fun & pleasure.

[Ethel]

A lot of transmission loss will be in the tyres. It's not exactly the same as rolling resistance as the faster the car travels the more torque needs to be applied through the tyres to overcome the drag on the body.

[Cooperman]

Always remember that the aerodynamic drag increases as the square of the speed. So if the speed doubles there is four times the aerodynamic drag. That is why reducing the drag as described above is so beneficial in terms of top speed.

[Ricewind]

Wow, a thread revival after almost 12 years! Is that a record?

 

The achievable maximum speeds depend on so many factors.

The final drive is very important as if a high ratio final drive is used to give cruising at lower revs, then top speed may well be lower as the peak torque and peak power points will mean it may not pull through to top speed in top.

 

Then there are the various drag-increasing items which may or may not be present.

If maximum speed is important, then remove the huge external rear view mirrors and just have a small bullet shaped on on the driver's door. Remove the wheel arch extensions and run with narrow wheels and 145 section tyres (that may also improve the handling). and fit a flat tray under the rear sub-frame. Just doing that could easily put 5 mph or more on the maximum speed. A 3.44:1 FDR is also god on a 1275 and a 3.76:1 on a 998 or 850. Yes, it will rev, but it will then pull max. speed at somewhere near peak revs.

 

But even doing all that, a Mini will still be a slow, old classic car, but will give a lot of fun & pleasure.

Hi yes I have just started my project after being absent for some time and so some of this old stuff is new to me. On my previous car I changed from 145 70 12's to 185 50 13's because I needed VR rated tyres. It transformed the handling but from what you are saying about, 145's possibly improving handling, my experience may be down to going from cheap tyres to Yokohamas. I would like the more aerodynamic 145's but can they be had in VR rating.

Edited by Ricewind, 16 January 2017 - 02:29 PM.

[Cooperman]

What car are they going on to need a VR rating? A VR rating is for above 130 mph up to 149 mph. That's faster than any road-going Mini I've ever seen, except hot-rods with different engines, but they are another matter.

[Ricewind]

My car is a modified Berkeley T60 with Mini running gear sub frame etc. It has an 850 Mini engine in at the moment but will have a 1380cc engine soon. I had a 1380 one previously (1990-2004)  that I lost in an accident. When I first got it and tried it out at high speed it started to lose stability after ten minuets or so and on inspection the rear tyre had transformed it's concentricity to resemble a deep fried and battered onion ring. The car has a smaller than Mini frontal area and very aerodynamic 0.27CD. The car had a smooth flat bottom including the engine bay and just one wheel at the back which aids stability at speed. The previous owner had it for two weeks before he lost his license after being caught on a speed gun at 140mph. I put in an accurate digital speedo and found that it would do 145mph but later when I tried it out with a sat nav I discovered that this was 150mph, I put the discrepancy that started at about 110 down to the centripetal forces expanding the tyres. The engine was built by Jonspeed of Nuneaton and the diff. was a 2.9/1. The 1380 that I now have is a different engine but is offset bored with Powermax pistons and a gas flowed head.

[Cooperman]

Ah that explains the high-speed tyre requirement.

 

Not many people know what a Berkeley is. They were built in Biggleswade, Beds. The 4-wheel B95 was very impressive and I believe it had a Royal Enfield motorcycle engine.

 

I had a friend who worked at Vauxhall in the early 1960's and he had a B90 into which he fitted a much-modified VX4/90 engine. it didn't 'arf go and he used it for sprints and hill-climbs. Then he got wise and got into Mini Coopers  .  

 

I don't think I would want to do 150 mph in a 3-wheeler. I once drove/tested a Bond Bug and that was frightening at anything over about 55 mph.

Edited by Cooperman, 16 January 2017 - 05:06 PM.

[mister bridger]

I had one of these a few years ago, and as you can see, they are very light! Not sure I'd be wanting to go at those sort of speeds in one though.

 

Ooh look, 800 posts!

Edited by mister bridger, 16 January 2017 - 05:33 PM.

[Ricewind]

Basically what I have is a Mini that substitutes the practicallity of four seats and all that space for an aerodynamic sports car. Created by David Ratner (a Mini enthusiast) by combining the excellent handling properties of the Mini's rising rate rubber suspension etc with ex Blackburn aircraft engineer Lawrie Bond's Berkeley three wheeled microcar. I often wonder if the inspiration came from the racing success of Owen Greenwoods Mini based trike.

 

 

 

 

Owen Greenwood’s 1071cc controversial ‘three wheeler’ Mini was debuted in March 1965 and instantly showed potential. Six months later at Mallory Park’s Gold Cup meeting it shattered the lap record as, despite gear selector troubles, Owen and passenger Terry Fairbrother beat Chris Vincent and Colin Seeley to give the Mini its first big win. It was soon decided that this type of vehicle had an unfair advantage over other outfits and new rules were introduced to disallow it.

[mab01uk]

Greenwood's 'sidecar' at its prime

http://maximummini.b...-its-prime.html

Edited by mab01uk, 17 January 2017 - 10:59 PM.

[tiger99]

The Berkley conversions with Mini running gear were quite popular in the late 1960 or early 1970s. I had a Mini whose shell was no longer economically repairable. Unfortunately I could never find a Berkley for sale. No Ebay in those days. There was a 4 wheel variant.

Cheap, efficient little sports cars had much to commend themselves in those days. Perhaps not now, among the Chelsea Tractors and other bloated monsters...

[Cooperman]

When I was an apprentice in the late 1950's some of my colleagues built 'specials' typically based on the old Austin 7 chassis with Morris 8 brakes and aluminium bodywork.
I never fancied doing this and I bought a 1950 Ford V8 Pilot which was as quick as those specials and a lot more comfortable. But it did use rather more petrol being a 3.6 litre V8.