i have heard that a 19% SC Pulley creates an overboost. Is it dangerous to the life of the engine?

 

SCs are not turbos, so they don't 'overboost' in that sense.
The 19% does increase boost, and heat, and can slip due to the tighter wrap.
It's possible that the boost and heat will tire out the squirrels more quickly, though there are no definitive studies.

 

so with the intercooler and an oil catch can there should be no problem then?

 

I've heard of several people with the 19% that go into an overboost condition and the car goes into limp mode. This is not an overboost per se as in turbos but the OEM ECU recognizes the pressure generated by a 19% as a higher than expected boost and does not like it.

Plenty of info around here on that, do a search

 

Yep....can throw a code with the 19's. You can spin the water pump too fast and may cause problems with the other belt driven parts if you spend to much time at or near redline.

 

John at Lucky Dog Garage claims that anything more than a 15% pulley is of little value as the stock SC loses compression efficiency (method for accounting for all the power losses that occur between stagnant suction and discharge pressures) with the 17 and 19% pullies. As discussed above, driveability is also negatively affected (error codes, etc.)
A lot of folks swear by the 17 and 19% pullies, but it would great to see a side by side dyno for the 3 pullies on similarly equipped vehicles that have each been properly tuned by LDG, Helix or Webb.

 

supercharger is only meant to spin at a certain rpm

 

#1

 

I had a 15% installed by Randy Webb (40k miles), a 19% with the Helix/Giac flash, later with LDG’s (32k), and an 11% with the LDG flash (2k); does that count?

The 19% served its purpose; provided lots of mid range torque, improved acceleration, performed without causing any failures, and no associated fault codes.

 

where did you get the 11%

 

the first time i heard a 11% too...

 

If you push the engine to redline constantly, a 19% isn't for you, as it does push the blower outside the preferred efficiency range. I found out the hard way; after 50k miles on my M45 with a 19%, the rotor coatings were hosed and the blower wouldn't compress as well as new [about 2psig worth of loss].

If you drive your MINI mainly around town below 6k rpm, then a 19% isn't a bad thing. Remember to use a short belt; 1365mm Goodyear Gatorback was my favorite for not slipping, but expect to change it every 9k miles; 19% is a small pulley and you have to transfer about 70HP through it to drive the blower!

 

I'm confused. Why are you asking this question?

Your sig. says that you have a 19% and a 3%. Are you just now concerned with what you may have gotten yourself into?

I for one RARELY take the car to the upper limits, and would rather have a nice fat mid range.

Do tell us all about your 22% combo!?!?! I was considering it myself.

 

Lol... the thing is that i had the other MCS but had an accident, now i bought this car a week ago, so i am concerning about the life of the engine runing with all that reduction... But i have to say it is running very hard! it is awesome... i have yet take it to the dyno, but it is around the 200WHP

 

Ive got 30K plus on a 19+4 combo.

21-22psi, lots of tirespin down low. I like to spend time up around redline. No problems whatsoever.

 

You're my hero.


Any tune to go along with that?

 

Whats your redline? Mine is 7600rpm and it comes up very fast.

 

Stock redline. I have no problem doing large burnouts bouncing rev. Never overheated on me once.

No tune, Just larger injectors. I hadnt planned on keeping this motor in the car this long, so I never even really thought about dropping cash on any kind of ECU work, other than an AFC to lean it out a bit.

 

Yes that does count, and that makes alot of sense that the 19% would be good for low--midrange torque even if it loses a bit over the 15% with regard to high rpm hp. I use the whole rpm range regularly, so I'll my pulley at or below 15%. My JCW pulley is at 13.8%, so I don't have much of an improvement to look forward to (maybe 3-4hp), but an LDG tune should add 5-7 horses.

 

19% here. I have about 6,000 miles on it. I would guess that I hit redline or close to it almost every day and I do 90 miles a day to work and back. I'll change my belt every 10k or so and other than that, no worries here. Might upgrade to a bigger crank pulley next year, but I don't plan to have the car still at that point.

 

Everybody who has a 19% do not have any problems.

Everbody who hasn't got it telling us about the problems.

I have 19%. Redline, trackdays,....no problems at all.

 

And that's why I went with what I did. Nobody actually reported any first hand problems.

Add to my list 2 auto-x too where I never left 1st gear.

 

Agreed, no problems here after nearly 70K with the 19% pulley. Never broke a belt either, though they do get changed every 15-20K just to be safe. I put about 10K on the car with a 15% prior to going to 19%. The 19 gave noticably better power in the low to mid-range, with no obvious difference at high rpm. No dyno numbers, so I suppose it is possible that the 15% makes more power at high rpms, but it isn't enough for me to tell the difference on way or the other.

Still on the original M45, waterpump, clutch, etc. The head has never been off. I've gone through two PCV valves and one coolant thermostat and that's about it in the driveline.

I don't drive very hard on a daily basis, though I do have a 90mile round trip commute to work. Most days I don't go much over 4000rpm and maybe 1/2 throttle, or occasionally wider throttle openings at lower rpm. If the mood strikes, I may run up to 5500-6500rpm full throttle, but only in 1st or 2nd and not every day or even every week.

On the other hand, I drive the **** out of it when autocrossing, and have never thought twice about running into and on the revlimter in 1st or 2nd if the course demands it. Rev limiter is 7325rpm. No track days, and no sustained high rpm or long periods of full throttle. Typically about 25-35 autocrosses a season, starting late in the 2002 season.

Scott
90SM

 

19% and love every minute of it only problem is a few limp modes, but restart the car and its good again. i dont even kow if that was from the pulley, as it only happened a couple times one week a year and a half after i put it on.

 

when limp mode means that the yellow DSC lamp lights, this occurs with more than 220 kpa pressure, which means more than 2.2 bar .
if you subtract pressure of normal air, about 1,2 bar or 120 kpa or 17,4 PSI boost is the border where DSC lamp goes on.
Staying with boost higher than 219 kpa will lean fuel/air mixture and damage motor after not a too long peroid.
So, when yellow DSC lamp goes on becasue of too high pressure because of too high compression caused by too low pulley size, throttle down immediatly .

I run in this mode every time in 5th gear at 7000 rpm and in 6th gear at 6500 rpm with a 15% ALTA V2 Pulley and stock crank pulley.

Please note that facelift chargers create slightly more boost than prefacelift ones.