*puts flamesuit on*
I think i'm probably the only one on here that has a mini with power output in each of those brackets so what i am going to say is not just opinion but based on my real life experience.
Moke A-Series: 1152cc ~50HP ATW
Mini A-Series: 1275cc SPi ~60ATW
Mini 4EFTE: 1330cc Turbo
1. 12psi boost ~100-120HP
2. 15psi boost ~140-160HP
3. 18psi boost ~160-180HP
4. 22psi boost ~180-200HP
miki wrote:
I just want some opinions on a theoretical question.
How much HP is usefull in a mini?
Having seen some incredible numbers with the engine conversions, xflow or 16 valve heads, I really wonder just what is the limit of HPs a mini can take and still be nimble / drivable? (so excluding any dragstrip antics)
I saw a YouTube vid of a clubby eng conversion where it looked as if the front subframe & entire front end seemed to want to part ways with the rest of the car. Trick of the light? Or just a case of too many ponies / torque?
I think everyone in this thread is right - power and drivability is all dependant on how you will use the car, what is it's intended purpose? weekend warrior / commuter / track day weapon / drag strip ??
The video on youtube of BIGBAD does have a lot of flex but that comes down to the subframe design (which was modified after that point) - that video was taken in the early days of engine conversions and was still in it's infancy and it did have an immense amount of torque/power that came on instantly when it hit boost - with a name like BIGBAD what would you expect

Kennomini wrote:
Over 100 at the wheels would be nice (hopefully I'll get that with my twinky). I figure the power to weight/traction balancing act would get to "unpleasant" with more that 200bhp and 10" wheels. Yes it would be fun but tricky to drive like a mini.
The beauty of electronic boost controllers is that you can choose the power you want and a nice number to drive around on for me is 12psi - around 140-150HP - much above that and it isn't fun around corners anymore (for turbo cars also depends a lot on boost delivery - mine starts boost from 2k and is fairly linear as it's a small ish turbo)
One thing which i know from my experience is that 10" wheels can handle a lot more power than 13" wheels though i havn't tried 12's. They just feel nicer, there is more grip, less torque steer at the higher power outputs and it's more comfortable. Part of it is the unsprung weight - I lossed ~25Kg switching back to 10's.
PDJ wrote:
More than 200bhp in a mini would be near enough useless. Unpleasant is an understatement.
You get people bragging "oh it'll spin the wheels in 3rd" Good on ya, so it's no good then.
People can get power hungry very quickly and end up ruining their car. 100bhp at the wheels in a mini is probably too much to drive it enthusiastically, safely, and legally.
Certainly not unpleasant, it's one of the nicer things i've done actually

As above the beauty of boost control is that you can choose your power and when you want it.
Options:
1. Normal Cruising lets choose ~140HP
2. Starts raining, drop it to ~120HP and drive off boost
3. Corners? 140HP
4. Corners with straights? 140HP with gear based boost building based on speed and gear choosen so it automatically varies based on your needs
5. pull up next to a *insert fast car of choice / ferrari, porsche, GTR, WRX, V8* select appropriate power for some fun.
6. drag strip up to max boost of course
7. track day as per point 4.
I have never been in a mini that is so flexible, drive it off boost below 3000rpm and it feels just like a rover, quiet, comfortable, fuel efficient, 5th gear up hills (on boost) but it's has a real jekyl and hyde personality if you want it to and that's what makes it special to me.
Yes you can spin the wheels in 3rd gear - it's very impressive

but as above no one is making you do it, guess what - if you don't want wheel spin choose a little less boost in 3rd at that speed and add a bit more when you get to 4th (I needed it when I was at wakefield park chasing a skyline down the straight)
If you're not going to use big power in a safe environment of your choice then of course it's not needed and a waste but that wasn't what the OP asked. "how much power is usefull" and that is why everyone in this thread is right- it's how much power is useful to them - it's not a one size fits all proposition otherwise we'd all have 35-75HP engines...
PDJ wrote:
I had a VZ SS Ute. Always wanted a V8 and it was glorious. Only problem was, give it the beans 1st and 2nd, get into 3rd then you'd have to back off.
Some people do drive their cars on the track / drag strip and giving it the beans in 1st through to top of second (legal limit onto fwy) is some of the best fun i've ever had in a mini. period.

PDJ wrote:
What are the good things about a mini? It handles like a go-kart, you can drive the arse off them, and they are fun. As soon as you start going BIG HP you lose some of the fun because you can't drive the arse off them, You're not thinking of the best way to keep you're momentum going when you get to a big hill. It's just squeeze the hammer down and ride the torque curve to the top.
I agree on your first point but don't agree on the second - you don't lose any of the fun you just gain a different form of fun - it still handles like a go-kart (in fact my car handles very well now, better than most but it does take a lot of development, time and work to get that result - it wasn't very good when i first built it and there are still improvements been made)
PDJ wrote:
Anywho, I'd say between 35 -75BHP at the wheels would be the go without losing the key characteristics of a classic mini

I actually do agree with you on that power range depending on the purpose but 75HP ATW is a nice number for an A-Series but don't discount more power unless you have tried it.
simon k wrote:
PDJ wrote:
It's just squeeze the hammer down and ride the torque curve to the top.
and I've gotta say, with just shy of 90hp at the wheels, doing that is just glorious, absolutely f*cking glorious
Where is the *like* button?

I still remember our little drive in brads 4EFTE when you screamed like a school girl like it was yesterday - the fit of joy/laughter still makes me happy to this day
drmini in aust wrote:
I have hung on in Josh's 200 ATW Starlet Mini and it was torque steery in the dry in a straight line and deadly in the wet.

Hardly usable, really.
150 ATW would be a safer bet for road use.
It's been a few years since then Kev - I've spend a lot of time working on the suspension and driveline - different alignments / bushes / roll bars/ wheels/tires/ steering rack and have dialed out a lot of those characteristics.
adamstuart wrote:
I'm with PDJ.
Great, your car will spin the wheels in 4th.
But you have to spend most of your days idling around at 1500rpm otherwise you're speeding.
I think anywhere from 40-70 would be great. Not to say I wouldn't take more if it were thrown at me, but I wouldn't be blowing big bucks to get to triple figures.
To me, driving a mini is about preparing for corners, hills, merging and stopping.
If I wanted to be able to just jam on the brakes when I need to stop and slam my right foot down when I needed to go, regardless of what is infront of me then i'd drive the auto 3L daily.
To each their own Adam
I wish i could spin them in 4th

Yea but my 4L daily can't go around corners

And there is still nothing like a mini taking on and embarrassing much bigger and 'faster' cars.
mini13 wrote:
this is largly dependent on suspension setup and how the engine makes its power, but around 150 hp ish is typically when it all starts getting a bit iffy,
I think this it due to being the amount of torque that stuff like the shell and subframe starts to distort and give unpleasant characteristics,
Agreed.
There is also something called your right foot which controls the power - you don't have to keep you foot flat and the fun/challenge comes from controlling all that power.
adamstuart wrote:
mini13 wrote:
this is largly dependent on suspension setup and how the engine makes its power, but around 150 hp ish is typically when it all starts getting a bit iffy,
I think this it due to being the amount of torque that stuff like the shell and subframe starts to distort and give unpleasant characteristics,
150 at the wheels?
I would expect things to get a bit curly long before then..
Up to 120-130 things are relatively sane, 150 is easily managable with a well sorted suspension setup and much above that you start talking serious concentration and a well sorted setup.
/flamesuit
