Believe it or not I did a search. I am about to press 'checkout', and I just want to know if there is anyone here who has actually owned and used both pullies. I am not one to rev too high -- rarely past 6500, and I want to know what is going to work best for me. I want to be safe first and foremost.

Is the difference significant?

 

I've had 15%, 15% + 2% crank,17%, and 19% pulleys, and currently am using the 17%. I have a very highly modified car, and want that extra bit of power offered by the 17 over the 15% pulley. The answer to your question is a function of what you expect and how you drive the car. Since you didn't mention any other mods, I'll assume that you have none.

There are many cars out there with just a 15% pulley and most people are quite happy with that modification. If your car is a daily driver and you want that occasional extra oomph from a pulley, then I think you might want to go the 15% route. IMO, the average driver probably won't be able to discern the difference between 15 and 17% pulleys. If you do go the pulley route, then you might want to consider an ECU tune after a while. Lots of people have reported better and smoother responses with the pulley after they have the car tuned, and there are a number of options for that.

Good luck...

 

I appreciate the response.

Today I spoke with the guy who will be doing my install (very reputable shop for MINI's) and he said that I should absolutely do 17%, because there is a very noticeable difference. He also said that if I plan on doing any other mods (which I do - intake, one ball) the 17% would be a better bet, because it has a lot more potential than the 15%.

I really don't know what to do. I love torque and don't really rev too high, but like to get on it at lower (<6000) rpms. However, I absolutely can't afford to blow my engine.

One or two more opinions confirming that there ISN'T a huge difference and I'm sold on the 15%.

Thank you all very much!

 

If you're not revving high, 17% should be just fine, you'll get that torque down lower. If you're tracking, IMHO the 15% is better; you'll be generating a bunch of counterproductive heat without any increase in power at higher RPM's with the 17%, but if you don't live up there, the 17% should be fine.

I'd still do a 15% though, if reliability is a consideration. 15% just doesn't lead to issues with the supercharger and belts the way 17% does, and I personally don't think the difference between 17% and 15% warrants the risk. Just my opinion, you'll find many who feel the opposite.

 

Stock vs 15% vs 19%

I know you asked about 15 vs 17, but this should give you a general idea of what different pullys do for gains.

 

That is amazing - exactly what I was looking for.

As for the numbers, the difference between the 15% and the 19% is huge! Much bigger than I expected. I would assume that 17% would fall right between those two, and even that is quite a difference.

 

I have owned one mini with a 15% one with a 19% and my current one has a 17% with a 3% crank pulley, and from personal experience the 19% was the fastest. the cars with the 15% and 19% both had alta intakes as well, and what a difference. My current car has the 17% with a 3% oversized crank pulley, alta top mount intercooler, alta intake, and a dinan throttle body. Even with all that, my car with the 19% was the fastest, just my 2 cents though.

 

I did 15% at first and within 5k miles, switched to a 19%. Would never go back.

Also, I could be wrong, but it's pretty impossible to blow your engine with a 19% pulley. It'll probably shorten your supercharger life, but I doubt it'll affect your engine.

 

From what I've read, it all depends on where you "live" with regards to engine speed. if your daily driving, it's fun the get the power down low, but your top end can be dangerous. lots of heat and over spinning the s/c.

I went 17% after my research. I don't live in the high RPM although I hit them on the occasional on-ramp, or back country road, but I shift out pretty quickly. if you have friends in the area with modded mini's or a local mini club, you could ask around for rides in their cars.