OK, call me conservative.....
I live in the Pacific NorthWest, where the streets are rain slickened in the winter. I will be teaching my (new driver) son about driving fast the proper way (at the track). But until I am sure that he will not wrap the car around a pole in the wet, I do not want to hand him the keys to an '04 MCS with the power it has to offer. No flames please-- I can remember being 16 all too well!!

So I am looking for an easy and reversible way to cut down the power in an MCS to about 125 hp. (I know, I know... but I don't want an MC). The simplest way (I think) is to put a restrictor in the exhaust. I was thinking of inserting a metal plate with a smaller hole in it, just south of the cat. An exhaust flow restrictor would leave the low end torque (mostly) unaffected, I am guessing up to about 5000 RPM, and progressively cut out the fun at the top end. The metal plate would be cheap to modify if the first size is too small or too big.

3 questions. First, is there an easier way to reduce the power to about 125 hp? Secondly, will restricting the exhaust cause OBDII to throw codes/check light errors at me? Finally, any long term damage to internals?

 

The extra 40 or so hp is not going to stop him from spinning the car into a pole. But for piece of mind, I guess one way to reduce power would be to get some custom software made.

I wouldn't think that restricting the exhaust that much is such a good idea for your engine...

 

Welcome to NAM, Daily Driver! Yours is the first thread of this type I have seen on NAM. I will be interested in reading the responses and will closely monitor them for flames. Kudos to you for planning how to make your peppy MINI safer for your son.

 

How about running 87 octane gas? That will cause the ECU to retard the timing, which will drop the hp & ft/lbs.... The only thing is, I don't know if it will drop the hp & ft/lbs to your target level.

Idea number 2: Pull the s/c (or, just bypass the s/c pulley; you will need a different belt size). That definitely will drop the hp & ft/lbs (maybe even more than your target).

 

Oh yea...what about running an oversized s/c pulley? 15% increased pulley instead of a 15% reduction pulley

 

I considered posting that idea; but it would require some non-trivial machining. Of course, if Daily Driver is up to the challenge, slowing the s/c (through an over-size s/c pulley) is definitely a way to get to the targeted power reduction.

 

If he was gonna wrap the car around the pole with 160hp in a MINI...he could do it with 125 hp in a MINI. The car is a small sports car....if you want to go fast and drive "crazy" its possible even with 125 horses.

Don't take this as a flame...take it as advice from a 21 year old who has grown up enough to realize that i have definitely matured from the 16-17 year old drive that i was when i first bought my MINI. I had a 115 hp MC and it could definitely get going fast enough to get me in trouble. You would have to get the car down to 80hp to really fully stop your kid from going nuts with the quick and nimble car.

The thing that kept me safe and out of danger was honestly the talks my dad gave me...and the lessons he taught me about saving the "fast" for the track. I fully believe that outside of buying your kid an old/slow car, the best way to keep him safe is to make sure he understands the dangers.

Just some thoughts from a younger MINI driver, who has grown up enough to reflect on his "younger driving" experience with an MC.

 

I thought about running an oversized (-15%) pulley..... is the OBDII software able to handle such a change?

When putting on a 15% 'faster' pulley, most people reprogrammed their ECU's. Is this because they have to (i.e. because the OBDII throws off a code) or to maximize power? (or both?)

 

I have seen a VW Rabbit with a N.A. diesel engine (56 hp) get wrapped around a telephone pole - the driver hydro-planed and swerved and guess what? Hello telephone pole....

It really comes down to the counseling sessions. Maybe a trip to a body shop (or emergency room) for re-inforcement?

 

The right way to do it would be to ask MTH to change the rev limiter to 4000 rpm. That's the way the ZR1 valet key works. The bright side is you could later easily upload other software (even the stock one) yourself to reverse the mod.

But that just means the MINI would be wrapped around a pole when going downhill rather than uphill... so it would be best of all to invest in a driving school for the little tyke.

 

Great suggestion for the "tyke," BFG!

 

Yes.

Re-programming the ECU is done to increase the power; but is not required. I have a 17% reduction pulley on my car with stock ECU and no codes or other problems.

 

Also, the Unichip reprograms the MINI to not run as rich (no more soot on the exhaust pipes).

 

AMEN. Exactly my thoughts.

 

How about a throttle body plate restrictor.....
Try this: take a thin aluminum plate 1/16" thick, 80mm X 80mm square
cut a 45mm hole in the center and 4 holes for the bolts. Sandwich the plate between the plastic supercharger tube and the Throttle Body.

The plate will restrict air flow
cut down on Horse Power dramatically and incredibly easy to reverse.
Do some testing, if the HP level is to high make the hole smaller and vise versa. The other positive is that you will run richer so no risk of overheating or detonation This is nothing unusual as it's done on a lot of MINI's in SCCA if the car is to fast....

Feel free to call me if you need some help.

Peter
Team M7
562-608-8123

 

A responsible parent.....I think you're part of a very small minority, but I'm cynical that way.

This isn't just a good idea because of rain slick streets. Your son may be one of the rare responsible ones, but a MINI is a fun car and (as I recall from my own misspent youth) friends with un-fun cars always want to ride with someone else.....someone with a fun car.....and that's a great recipe for lead foot driving.....a strong temptation for peer-pressure susceptible kids.

Okay, that's enough "old guy" pontification; back to the question at hand.

If you're looking for cheap, simple and reversible, Peter has the right idea - go with the restrictor plate.....but don't tell your son about it because it'll be as easy for him to reverse as it is for you.....maybe even easier.

 

Good thread...Alta sells a +10% Supercharger pulley, however there's a lot of work in changing a pulley.

I wouldn't run low octane gas...that's just a gamble with the internals of your motor.

I like Peters idea, the Throttle body is soo easy to take off and put back on, that might be the way to go.

Also MTH offers software that you can lower your redline...which will dramatically loose HP since you can keep him out of a lot of the power band.


Keep us posted! -- Johan

 

Get a one or two year lease on a Chevy Aveo. You'll solve the hp issue, and also give him an incentive to work his way "up" to the MINI.

 

I say give him some driving lessons and let him go! Find some video's of some crashes, roll overs, etc. on the internet and show him. I'm only 17, but I don't act like an idiot when I drive...sure, the powers there, and very tempting I might add, especially since I did the pulley! but that doesn't mean I have to use it all of the time.

If you don't think he is responsible enough, and will get hurt, then don't let him drive it until he has proven to you that he IS responsible enough and won't wrap it around a tree. I would say, if he doesn't have a job, make him get a job..then he'll realize how hard it is to earn money...thus buying you a new MINI if he crashes that. Hopefully no lose of life would be invovled...but kindy remind him every now and then what he is driving, and what the car is capable of.

-Cody

 

Viewpoint from another younger MINI driver, I'm 18, got my MCS when I was 17 and pullied it just 4 months after I got it. Like many have said, a 125hp MINI will still be easy to wrap around a tree. No offense, but the amount of power a car has doesn't reflect the driving style of the driver. Sure, it'll take your son a longer time to get to higher speeds but if he wants to, he'll do it.

I quickly learned my lesson in driving above the speed limit after being pulled over on the way to school. Best way for your son to be safe is to EDUCATE him, not take away power. Instead, teach him how to handle the power. Just my .02, coming from a young driver that used to be irresponsible...

 

could add a small block on the gas pedal to limit travel.

 

govener.... simply have a unichip program made that stops the max speed at 80mph.

 

You could still do SO MUCH damage at 80 mph.....speed limiting isnt gonna stop a 16 year old in a car that handles like the MINI does.

Car is limited to 80mph...the kid hears that his car can really handle well from one of his friends.....kid goes around tight corner going 45mph (well under the 80 mph limit). He overcooks the corner, over-corrects the steering (due to lack of driving knowledge), and goes off into the ditch.

Like i said....get the car down to 125 hp and limit it to 80mph and you can still cause problems. The truth is...going 45mph and 0-60 in 10 seconds can still be dangerous in the wrong hands....you just need to make them the right hands by educating him.

 

Wow! really.
I must have a defective one

 

Holey NASCAR Peter!!

Ya beat me to it.