Power vs. Breaks debate

Miniacs,
This issue is something that comes up so often, and it's really beginning to annoy me. It annoys me, not because it comes up often, but more, because after loads of postings I still don't really know what to do. I have a '85 mayfair with 998cc. It has wide alloys and stage1, plus lots of other non-go-faster things like spot lights and a white roof! It goes pretty well, but I would really like to get another engine to take apart and tune up. I'd like more power so I am considering a 1275 with a decent cam and skimmed head, etc. The main problem is those bloody front drum brakes. Everyone always says 'Aargh, whatever you do, don't increase power without going to discs!!' in a worried 'we're all gonna die!' tone of voice. That leaves me thinking 'Damn! If only I'd bought a mini one year newer!!'. It seems I have three choices:

1) Buy another later mini (no way! not after all the work I've put into Borris)
2) Get some Cooper S discs (aparently very rare/expensive)
3) get 12" wheels and go for normal discs (also too expensive).

One thing is really puzzling me though. A bigger engine means more power, therefore more acceleration capability, but not necassarily more speed. I drive fairly fast as it is, and my brakes are very good. I have decent shoes and I keep them in top adjustment, and can lock the wheels no probs. Having a bigger engine would mean I'd get upto the same speed quicker, but I'm not pressing the brake pedal when I'm speeding up, so why do I need better brakes. The momentum of the car would be less if anything since more steel is missing from the inards of the engine! Could someone please tell me if there's something I'm forgetting here!??

Scott

PS: Would a servo on drums be adiquate. Doesn't that just decrease pedal-effort?
PPS: And before anyone says to buy 'Tuning BL's...', it's here infront of me!!

Scott,

I think the idea is that with the bigger engine, you car will be going that much faster in almost all situations. So let's say your on your way home one night and your feel like a bit of spirited drive. You brakes will have to work much harder everytime you slow down because they've got to shave off that extra 10-15mph. Slowing down between lights, approaches to round abouts, junctions etc. The drums and shoes will be running that much hotter, which is where the trouble starts. Drums are much more prone to brake fade that discs, and although thats not so much of a problem with 40 bhp mini's, you're new 70-80 bhp mini will loose it's stopping power pretty soon into a fast city drive.

You don't want to risk ruining all that hard 1275 work. Anyway discs are cool because their self adjusting.

I got my discs with callipers, swivel hubs and shafts for £120.00 for Just Mini's in Forest Gate. Although the discs themselves had, had it, I managed to get a new pair from Mini Spares for £9.00 (they came off modified Coopers destined for Japan).

Don't worry about 12 inch wheels. I can predict that minilites are going to fall in price, due to all the people who are going to go out and buy the New Extreme minilights.

Tamer.

Hi Scott,

Interesting question this one. I will attempt to shed some light on it from an OZ perspective.

My rough and wrinkly old 1000cc Clubman has power assisted/boosted drum brakes all round. I have found that these are adequate for the acceleration/performance of the vehicle. By comparison, they are *MUCH,MUCH* better than the brakes on a friend's Clubman. The only difference between the two cars is the booster and both of us keep our brakes adjusted properly.

However, I was enquiring about upgrading and putting a 1275 into it and the insurance company would not accept the modification unless I fitted boosted disc brakes to the car. Now I know there are several (many??) 1275 or larger powered minis in OZ with drum brakes on them. I can only assume that their insurance company does not know about one side of the engine/brake combination. That is, by omitting to mention the drum brakes or the 1275 motor at insurance time.

I am also told (unnoficially by a friend in the business) that all 1275 powered minis in OZ had disk brakes as standard (Cooper S, GT, LS etc). This was a legislated requirement and if an engine swap to 1275+ is done the brakes *MUST* be upgraded to comply with registration requirements (in addition to the insurance requirements previously mentioned).

I believe that this rule in OZ is a good one because *brakes save lives*. My advice is to shop around and put the biggest and best brakes on that you can afford regardless of motor size. After all, you can control the amount of acceleration you use but you have no control over some di**h**d or farmer Blogg's cow that suddenly "appears" in front of you.

Cheers!!

Neil

On Fri, 14 Feb 1997, Neil Williams wrote:
However, I was enquiring about upgrading and putting a 1275 into it and the insurance company would not accept the modification unless I fitted boosted disc brakes to the car.

I am also told (unnoficially by a friend in the business) that all 1275 powered minis in OZ had disk brakes as standard (Cooper S, GT, LS etc). This was a legislated requirement and if an engine swap to 1275+ is done the brakes *MUST* be upgraded to comply with registration requirements (in addition to the insurance requirements previously mentioned).

No, this isn't quite true. There isn't an act of Parliament relating to Minis with 1275's and disk brakes.

To be accepted by registration authorities, a particular vehicle configuration must be certified by an engineer as safe. The car companies spend considerable sums of money doing this for their standard range of models. If you want to modify your car you have to modify it to a configuration of another recognised model if you want to get it regisitered without requiring an engineer's report. If you do something non-standard, like a V8, you need an engineer's report saying the vehicle is roadworthy before it will be accepted for registration.

All Minis with 1275's officially sold in Australia had disk brakes, so the only easy way to install a 1275 is to also install disks.

Does this mean that you can't legally fit disks to a 998? Yes, but a mixture of common sense and ignorance prevails.

Dean

The main problem is those bloody front drum brakes.

Everyone always says 'Aargh, whatever you do, don't increase power without going to discs!!'

I must admit, that I would go along with that.

One thing is really puzzling me though. A bigger engine means more power, therefore more acceleration capability,

If you've got better acceleration, it makes sense to have equally good deceleration - doesn't it? I am very much aware that my drum brakes are nowehere near as good at stopping me as I'd like them to be - and that is with an 850 engine.
I know that going to a 1275 doesn't necessarily mean more speed, but come on - you're not going to a bigger engine to tootle along as usual, are you?

But, really, why is everyone so shy about admitting how they solved this problem? For those of us with 10" wheels it seems to come down to:

a) Spend GBP 400 on Cooper disk brakes
b) Spend GBP 400 on 12" alloy wheels and disks off a 12" wheeled Mini (scrappers, ofcourse)
c) Spend GBP 400 on getting MG Metro 4 pot calipers etc. modified for 10" wheels.

Like the author of the original message, I am wondering - do I REALLY need to go for better brakes?

And if so, before I land myself with either an undriveable car, exorbitant bills or completely ruin the Metro parts I have scavenged, I would love to hear from all of you who have ANY facts that may help.

Is there someone out there who has actually done the conversion? What was your experience?

If everyone could send me any and all information on this subject, then I will collate the information and place it on the WWW for all to use. Not only that, but if I feel confident that I have a technical solution, I will even have a go on my own car and chronicle the procedure. That way we will never have to ask these questions again.

---
Regards,

Paul Slootweg

Time to settle this once and for all!!!

Have you ever experienced that sinking feeling coming into a tight corner and you know that the brakes are not going to get you to the desired speed to get around that 90 degree left??

If not then you should try it one day....it certainly opens up the adrenal glands, bladder and tear ducts (in that order!).

When it comes down to brakes, don't piss around. Get the best. If you are going to put anything more than standard horsepower through your standard set-up then things are going to go pear shaped. End of story. If you can't afford the best then don't buy that "super dupermega engine", wait a while and get the brakes first.

Judging by the crap driving in the UK......TAILGATERS im talking about...yes you know who you are......the best brakes are an absolute NECESSITY. For that little bit of extra expense the extra safety is more than worth it. Think of the hassle without your car after you put it off the road into a ditch. Think of the insurance claim headaches. Think of what your life would be like if you mowed a kid down all because you were too mean to uprate your brakes.

THE MOST IMPORTANT ITEM ON ANY CAR IS ITS BRAKES....DON'T SKIMP ON THEM!!

A simple eye opener for those of you still dubious about the subject.....take a walk around a scrappies and look at all those crashed cars. Then imagine how the occupants got out....using their two feet, one foot or dragged out into a body bag. The choice is yours.

Yours Sensibly,

Neil.

At 09:20 PM 2/14/1997 +1100, Dean wrote:
No, this isn't quite true. There isn't an act of Parliament relating to Minis with 1275's and disk brakes. I STAND CORRECTED. WRONG CHOICE OF WORDS I'M AFRAID. SORRY

To be accepted by registration authorities, a particular vehicle configuration must be certified by an engineer as safe. HOWEVER, IT IS INTERESTING THAT INSURANCE COMPANIES SEEM TO GO WEAK AT THE KNEES WHEN YOU PRESENT A "MODIFIED" VEHICLE REGARDLESS OF HAVING THE CORRECT PAPERWORK DON'T THEY. The car companies spend considerable sums of money doing this for their standard range of models. If you want to modify your car you have to modify it to a configuration of another recognised model if you want to get it regisitered without requiring an engineer's report. If you do something non-standard, like a V8, you need an engineer's report saying the vehicle is roadworthy before it will be accepted for registration.

All Minis with 1275's officially sold in Australia had disk brakes, so the only easy way to install a 1275 is to also install disks.

Does this mean that you can't legally fit disks to a 998? Yes, but a mixture of common sense and ignorance prevails.

NO IT DOESN'T, YOU ARE ALLOWED TO LEGALLY UPGRADE FROM THE SPECIFICATIONS INDICATED BY THE ADR's FOR A PARTICULAR VEHICLE. THIS DOES NOT NECCESSARILY MEAN ENGINE CAPACITY BECAUSE MOTOR SIZE AND BRAKE REQUIREMENTS OPERATE IN PARALLEL AND THE ONUS IS ON YOU TO COMPLY. ie THE SMALLER TH MOTOR THE SMALLER THE BRAKES AND VICE-VERSA. (ESPECIALLY IF YOU ARE USING "STANDARD" PARTS FROM ANOTHER MODEL IN THE RANGE. IF YOU CHOOSE TO FIT SAY COMMODORE DISCS TO A MINI THIS IS DIFFERENT AGAIN AND REQUIRES AN ENGINEERS CERTIFICATE TO APPROVE THE WORK) THIS MEANS THAT "UPGRADING" TO DISK BRAKES FROM DRUM ON ANY VEHICLE IS ALLOWED UNDER THE CURRENT INTERPRETATION OF THE RULES. (DISC BRAKES HAVING GREATER EFFICIENCY THAN DRUMS) HOWEVER, TO "DOWNGRADE" IS NOT LEGALLY ALLOWED. EG. (not mini related) SOME 8 SEATER PASSENGER VANS STIPULATE 6 OR 8 PLY LIGHT TRUCK TYRES ON THEIR TYRE COMPLIANCE DECALS. YOU ARE NOT LEGALLY ALLOWED TO FIT PASSENGER TYRES (EVEN THOUGH THEY GRIP/HANDLE BETTER AND ARE BATTER TO DRIVE ON THAN LIGHT TRUCK TYRES) BECAUSE THEY ARE ONLY 4 PLY CONSTRUCTION. THUS, YOU ARE SEEN AS DOWNGRADING THE VEHICLE SPECS AND THIS IS WHERE THE PROBLEM IS. IF YOU OWN A 1275 POWERED MINI IT IS (QUIET CORRECTLY) ASSUMED BY THE AUTHORITIES TO REQUIRE THE BRAKING EFFICIENCY TO MATCH THE ENGINE PERFORMANCE. IF YOU FIT "STANDARD" DISCS TO A 998 YOU ARE "UPGRADING" THE SAFETY SPECS BEYOND THE REQUIREMENTS FOR A "STANDARD" 998.

AS AN ASIDE DEAN, HAVE YOU SEEN THE ADD FOR THE BOLT ON DISK BRAKE KIT THAT MINI KINGDOM SELL? (IT'S IN MINI MAGIC) I SAW IT IN THE FLESH LAST WEEK AND IT LOOKS LIKE A PRETTY GOOD THING. IT APPEARS TO BE A COMMODORE ROTOR AND CALLIPER WITH A LS DRIVE FLANGE. ANY CAR FITTED WITH THIS CONVERSION WOULD STOP ON A 10C PIECE.

CHEERS

NEIL

At 11:51 PM 2/14/97 GMT, you wrote: Hello everybody,

Time to settle this once and for all!!!

Have you ever experienced that sinking feeling coming into a tight corner and you know that the brakes are not going to get you to the desired speed to get around that 90 degree left??
[snip]
Yours Sensibly,

Neil.

I would say it depends on what kind of driving, and where. The twin leading shoe is more than competant, in a one shot, panic, situation. I can say from personal experience that it is not far off the performance of a 997 cooper. (disc)
The S brakes are superior, no question, but only after repeated application. The servo is there only to make you feel better,(re: pedal pressure) the braking capabilities remain the same.
Carl

Things don't need to anywhere near that expensive if you don't mind waitng a bit, I to had this quandry in the end I decided to put off the engine upgrade until I had the stopping power to match, what do I really want to do risk getting there a fast as possible? or be sure of getting there? I knew that one day my overenthusim for all those extra dragons would get the better of me..

I got my 12" revolutions for 100 pounds with tyres a bit of elbow grease and a can of green paint and they were great! (my friend just bought some MG pepperpots for only 50quid! and there in a1 condition!!)

Then I asked waited until a set of disk either came up in the clulb or a scrappy at the right price, 2 months later they did 45 quid (with new mintex pads) and they were mine total outlay 150quid!

I just didn't get it all instantly. With it all fitted you wonder why the hell did I hum and har?

Fitting was easy (believe me if i can do it ANYONE CAN) just take the old drums of with the old CV's, bang on the new CV's, then just bolt the new jewson lot together! What could be easier? It really was that easy. The ONLY bit that caught us out was the need for different CV's since the spline size is different

Go for it!

If not then you should try it one day....it certainly opens up the adrenal glands, bladder and tear ducts (in that order!).

I remember the day I got a set of improved front pads for the race car that were ventalated so the brake fluid wouldn't boil after about three laps - the brakes were working so great that I was really pushing the car (suprisingly though the lap times weren't much better... probably because instead of throwing it sidways I was using the brakes and at that tims wasn't used to driving the Min that way!). At about the 10 or 11 lap the seals blew out of the caliper pistons going into a 90 degree fairly slow turn at the end of the second longest straight - I could have sworn that the car sped up! I managed to throw it sideways to slow somw but as it was a bit later than I usually braked I also went sideways through the flag station, back accross the track and stopped about 12 inches from the wall on the other side! Drove the rest of the race using the hand brake ande still managed a fourth (I was pretty far ahead when the brakes broke and there were only four laps left - got passed by the other three cars - 2 minis and an alfa - on the last lap in the final two turns - sigh) But YES that total loss of braking is a religious experiance (God's name was involved!)

Lee

Yes, I'd just like to add that I do realise that discs are better. I just question the need for them if you're going to be driving as responsibly as with a small engine. If I could afford them, I'd put them in, since they are safer in conditions as above (i.e. when you really need them).

Cheers,
Hamish