121 replies to this topic

[George929]

mid 50s BHP from a well set up stage 1 998

Edited by George929, 02 January 2011 - 11:31 PM.

[maggies_minder]

just to add my 1275 with a stage 1 and 66BHP only got to 105MPH, thats on a rolling road with no drag/wind resistance.


if speed kills i'll live forever!

[mini_mad69]

I got my 998 to 87mph downhill, with a calibrated speedo.


That's all it had to give, on the flat was around 83mph. Standard speedo was reading over 90mph.


100mph+ is a 998 is just crazy, and a stage 1 kit will give you a higher top speed, as there is more power to push the car through the air.

A tall final drive can only take you so far.

[Shifty]

How on earth people are arriving at 100mph+ is unreal!!

well if the speedo says it it must be true

It must be a speedo calibrated by the "Easter Bunny Corp" which is owned by " Santa claus enterprises"

[Cooperman]

It's a factor of power against aerodynamic drag.
A 998 Cooper with the better head, better cam, twin SU's and a much improved exhaust, all of which gave 55 bhp, would do 89 mph. And a basic 998 non-Cooper with about 40 bhp, give or take a couple of bhp will probably do about 80 flat out on the level with no headwind.
Take no notice of the speedo as they are always over-optimistic.
By he way, a 34 bhp Mini 850 would do 72 mph.
The 1275 Cooper 'S' with 75 bhp would do about 96 mph.
So you see that from 80 mph, an extra 15 bhp gave about 9 mph more, but the 1275 with another 20 bhp only gave a further 8 mph. This is because drag increases as the square of the speed. i.e. double the speed gives 4 times the drag.
A stage 1 (whatever that really means - not all 'Stage 1's' are the same) will not give 998 Cooper power, but if get an extra 10% that would be 44 bhp, which would increase the top speed by about 4 mph, but it would show a better 0 - 60 time.
Of course, the gearing will affect things a bit and top speed would normally be at or around peak power rpm, although it is possible to 'over-gear' a car so that it won't reach peak rpm in top, due to being overwhealmed by the aerodynamic drag.
To do a genuine 100 mph requires about 82 bhp (it would be a 'demon' 998 that gave this power in a road Mini), whilst to achieve 120 mph would require about 130 bhp, but the gearing does really become an issue then as the engine is so modified that the power band is very narrow and ultra-high revs would be needed.
It is hard to improve the aerodynamics of the Mini, but de-seaming the vertical seams loses 44 sq. ins. of frontal area. An engineer friend of mine doubts that the so-called AeroD kits you can buy really do anything as they are more styling gimmicks than wind-tunnel tested aids. How do you improve the aerodynamics of a brick?

[1984mini25]

My uncles standard 998 does 85 quite easily (dunno if hes tried harder) , dunno where your all getting 100+ from.

Work it out yourself, and I did say they were theoretical top speeds going by the gearing alone.

http://www.guess-wor.../Tech/ratio.htm

[Shifty]

mid 50s BHP from a well set up stage 1 998

Mines at the wheels.

[Bungle]

you improve the aerodynamics of a brick?

easy remove the front and back screens

[Carlos W]

I've got a speedo app on my phone which uses GPS satelites, and shows my 52 plate mondeo and 09 plate Ibiza speedos are a few mph out!

God knows how far out my 27 year old mini speedo is as it's in a box somewhere!

[1984mini25]

A tall final drive can only take you so far.

True, the last time mine was on the rollers the power started to drop back off after 5.5k. So even with a theoretical geared top speed of 120 at 6k it will NEVER get there.

[Shifty]

It's a factor of power against aerodynamic drag.
A 998 Cooper with the better head, better cam, twin SU's and a much improved exhaust, all of which gave 55 bhp, would do 89 mph. And a basic 998 non-Cooper with about 40 bhp, give or take a couple of bhp will probably do about 80 flat out on the level with no headwind.
Take no notice of the speedo as they are always over-optimistic.
By he way, a 34 bhp Mini 850 would do 72 mph.
The 1275 Cooper 'S' with 75 bhp would do about 96 mph.
So you see that from 80 mph, an extra 15 bhp gave about 9 mph more, but the 1275 with another 20 bhp only gave a further 8 mph. This is because drag increases as the square of the speed. i.e. double the speed gives 4 times the drag.
A stage 1 (whatever that really means - not all 'Stage 1's' are the same) will not give 998 Cooper power, but if get an extra 10% that would be 44 bhp, which would increase the top speed by about 4 mph, but it would show a better 0 - 60 time.
Of course, the gearing will affect things a bit and top speed would normally be at or around peak power rpm, although it is possible to 'over-gear' a car so that it won't reach peak rpm in top, due to being overwhealmed by the aerodynamic drag.
To do a genuine 100 mph requires about 82 bhp (it would be a 'demon' 998 that gave this power in a road Mini), whilst to achieve 120 mph would require about 130 bhp, but the gearing does really become an issue then as the engine is so modified that the power band is very narrow and ultra-high revs would be needed.
It is hard to improve the aerodynamics of the Mini, but de-seaming the vertical seams loses 44 sq. ins. of frontal area. An engineer friend of mine doubts that the so-called AeroD kits you can buy really do anything as they are more styling gimmicks than wind-tunnel tested aids. How do you improve the aerodynamics of a brick?

Bang on!!

[BLUE ITALIAN JOB]

I don't believe any of these claims. I suggest you all measure the accuracy of your speedos and undergo a reality check.

speedo's checked fine , have you tried a good 998 even in std form - no they may not push you into the back of your seat but given time and the miles they will rev and rev very freely , now running 1293 with same gearing , only difference is the 1293 will get there alot quicker and will not slow so much when cruising along in lane 3 on m/way , out of the two engines i think the 998 is a much sweeter engine , and the 1293 may only give 30-35 mpg , and why do you find it hard to think of a 998 doing a ton , before the 997 cooper in 61 they were getting over a ton from the 850 - AND on drum brakes ..

[danrock101]

mine had 58bhp at the wheels to 99 on the satnav and carry on a little bit, ofc I would never do this on the road, it was in my back garden (I live in a mansion
the majority of speedos in cars read high by around 10%, don't know why just seems to be the case.

[maggies_minder]

mine had 58bhp at the wheels to 99 on the satnav and carry on a little bit, ofc I would never do this on the road, it was in my back garden (I live in a mansion
the majority of speedos in cars read high by around 10%, don't know why just seems to be the case.

i guess it for safety, they no most will speed or at the very least sit at the speed limit, by over reading you think your going faster than you are,
so its a backhanded all be it smart way to slow you down.

[mini93]

i find these threads funny