As I posted in a somewhat related thread here, you will see I'm shopping for a used MINI and that I test drove 2007 MCS a few days ago. In addition to what I thought was a rough engine note (the subject of the linked thread), I thought the engine seemed slow, and unhappy to rev quickly. Heel and toeing was difficult and not very fun because the engine was so reluctant to rev.

Is the flywheel on these cars just massive? Is this maybe a trait of turbocharged engines? (I've never owned, and barely driven, any turbo engines) What gives? Are there (affordable) lightweight flywheels available for the R56? If I buy this car I may give serious thought to installing a lightweight flywheel, it was pretty disappointing I thought...

 

I feel the same way about my new justa but I suspect it's caused by the delay inherent with the electronic throttle. I know the justa is a little anemic in the hp department but it should rev freely when the car is stationary. My previous toy car was a 1st generation Miata and the throttle seemed much more responsive.

 

I can only conclude that the '07 was tired and needs some attention. The justa might also be sick as slow revving is not anything I have experienced.

 

Did you have sport mode turned on? I've noticed heel-toes are pretty impossible with it off. Otherwise, the engine seems pretty quick and happy to rev. Especially after a tune

 

yeah +1 sport will open the TB a lot faster than normal i can heel toe the normal mode but wont get it smooth like i will with sport.

 

RPM could drop a lil faster too... If you watch the dash on a lot of supercars, the needles drop as fast as they climb

 

thats due to low mass flywheels and n/a motors. turbo cars run on boost which is dependant on load... a heavier fly wheel believe it or not helps boost be smoother. Lighter one would reduce mass but bring the curve upwards a little bit. I had a light weight flywheel on my s 2k and it revved extremely freely. just part of the design of the mini. Also heavier flywheels are more common in passenger cars as they also help MPG. more rotating mass = more momentum and less work for the engine at speed

 

This will mosty likely cause a lot of feed back, but I put the new Sprint Booster on mine and solved the problem. It is about two steps above the Sport Button. I do not sell them, work of anyone who does or gain any payment for recommending them. It simply works and I like it.

Jim

 

What signal did you have to interupt? tps and MAF?

 

If you are talking about the Sprint Boster, you just plug it in, between the throttle and the OEM throttle wire. Nothing else.

Jim

 

im sure it just modifies the tps (throttle position sensor)

 

That is correct, it does not increase HP or torque, but it does make the engine rev faster with just a tap of the foot. You can search a bunch of threads here that claim it does nothing and others that say it does. This is a device that you can not just do "paperwork theory" on. I have one it works. Try one and decide for yourself.

Jim

 

probably amps the signal from the pedal to the motor(throttle body) so it opens faster

 

Thanks, I'd been considering a Sprint Booster but maybe you've made up my mind for me. The general consensus here seems to be that those who have tried it, like it. Those that haven't tried it, consider it snake oil.

 

I've had the SB on all four of my MINI's and two of my Porsche's. The difference is noticeable the first time you accelerate from a stop sign or traffic light and no it's not the same as pressing the gas pedal harder.

 

+1 no matter how hard you press the pedal the throttle motor will open the plate 1 of 2 speeds.


Id like to see side by side speed of the sprint booster vs stock sport to see how much faster it is.

 

I use mine in conjunction with the NM torque arm bushing which puts the available power to the wheels quicker. With the Sprint Booster in red (race) mode I can make the wheels spin on my Cooper. It makes the revs so much faster, that in stop and go traffic I turn it off, as first gear is very touchy.

Jim

 

I agree. Makes shifts from 1st to 2nd gear a bit harder to smooth out

 

Although it is very entertaining accelerating, in stop and go traffic it almost seems like it decreased the throttle feel pressing down gas about an inch...i almost stalled...never had this issue with stock sport button on...sprint booster needs to work on the throttle response when lightly tapping gas...pressing little more than an inch will rev at 2500...way too touchy and i don't wanna have to turn it off and on

 

I only turn it off in HEAVY, stop and go traffic. Once you get use to it, you can zip right off from a light smoothly. The touchy problem comes when the person in front won't get out of the way, so you can go. It is not for everybody.

Jim

 

I see what you are saying. Adding the bushing to the torque arm told me I needed the sprint booster. Now the boster is telling me I need the short shifter. All three together should be a very nice set up.

Jim