i know i know another pulley thread, you're probably about to reply "search button," but now im getting serious about getting one and just dont wan't to make the wrong decision. ive eliminated the 19%, so now it's just between 15 and 17. i live in connecticut so we have cold winters and hot summers. i got my r53 used, so it has 98,000 miles on it and i installed an alta cai and a borla exhaust and i dont want to risk the supercharger failing especially because it has high mileage. i'm a daily driver and never track race probably the highest ive went has been about 5k rpm, and thats rare. all i see is mixed things, some say 17 is fine and some arent, some say the 15 has less wear on the s/c and some say its the same wear as a 17, just very confused. maybe new info has came up on this topic....thanks

 

There's really no difference in performance below 5k rpm. You'd have to wind it all the way up to see the small increase in power I think.

 

You will be happy with a 15%, but I doubt a 17% will damage anything unless you hang out at really high RPM. With your car as a DD I wouldn't worry about it. I actually wish I would have gone with 17% instead of 15%, but doubt I would be able to really feel a difference. I live in Indiana, not super hot summers but plenty in the 90s. Cold is your friend.

On a side note, I doubt the sincerity of your apology.

 

TOmmy, you might want to check your data. the 15% at high rpms is close to or above the affective working range and the 17% is definitely above working range at high RPMs. I just hit over 100k on my daily driver with similar mods and I am getting ready to add a 17%. Compression on my motor is fine and like you I don't rev the crap out of my car. I have done a ton or reading on this.

 

i have 103,000 on my car just did the 15% and tune (MAKE SURE YOU GET A TUNE) with the magna flow exh i am plenty pleased with it has tons of power when i need it. i live in Maryland so the heat is not too bad here also just done go buying plasma boosters or that Detroit crap they do nothing the 17% need to be run out in those bad rpms you dont want to be in them too long with out some head work done.

 

lol i am sorry, i see how it could be annoying when this question gets asked a million times...anyone else?

 

Just the opposite when I had my 15% installed. Noticeable improvement from idle to redline.

A 15% pulley is considered the safest because you don't overspin the water pump, etc. at high rpm. However, there are a lot of owners with 17% who have never had any problems and are very happy with them.

 

You are probably safe with either one.
I have the 15% just because it is very close to the JCW (14.7% IIRC). If MINI was willing to put a 15% on it is good enough for me.

 

A 17% pulley will make power earlier in the RPM range than a 15% pulley. This is due to the smaller size being able to spin faster. Getting a pulley depends on how much time you are in the high RPM's. If you don't hang out in the upper RPM's a lot then you will be fine with a 17%. if you are planning on tracking the car or are above 5k a lot, it would be safer to get a 15%. Peak horsepower numbers don't change to much with pulley size either.

You do not NEED to get a tune, your car will run fine without one. It will help get more power out the car as well as help pull everything together, but it is not necessary. Also head flow isn't really the limiting or important factor when dealing with pulley size, its about overspinning the supercharger and prematurely wearing it out, but if your not in the upper rpms too much then you should be fine.

Also, bioshift, what are you talking about Detroit crap? If you are talking about their Bypass valve, you are mistaken. Bad RPM's? Please elaborate.

 

i was no talking about flow the head already flows great i was talking about floating a spring or braking one at high rpms if you have a heavy foot titanium springs and retainers would stop that

 

the bypass valve that detrot tune makes does not really do anything except get stuck open. does nothing but make your butt dyno think your going faster

 

Split the difference Disregard the Out Of Stock , message there are more arriving Monday.

Randy
M7 tuning

http://www.m7tuning.com/parts/produc...&products_id=1

 

Hummm. First time I have ever heard of the DT BPV sticking open. Don't recall seeing anything about that in other posts. I have had mine for over 3 years with out problems. Wonder if you could elaborate.

 

Same here, I have only heard good things about it. It was meant to be more than just for buty dyno, it was created to get rid of the yo-yo effect so many people have experienced. I fear I'm starting to get it as well, have to wait and see I guess.

 

I say get the 15% and rev the crap out of your engine. You need to make sure that your oil temp is good (about 10 mins after the water temp is in the normal range) and be smooth about it. Cars are made to operate safely up to the designed redline. Honestly I see more cars that are not driven hard with engine issues than those that are used properly.

Don't be afraid. Even my old 1969 V-8 can do 5K rpms, the little mini can do 6800 without an issue.

 

For your type of driving i would definetly go to a 17% pulley.
If you want you can also take the 15% and put the cravenspeed 2% oversized crank pulley. If im nit mistaken that would give you similar result than a 19% pulley

 

Yeah, this is wrong info... It will not add HP but what it will do is make sure that the bypass butterfly is fully closed. It is also on a heavier spring thus helping to eliminate the yoyo effect. I have had the DT valve for several years and it has never "stuck" open.

On the pulley side... Yeah, go 17%. I have that in mine now and if you look at my sig I was at 15%. There is more power down low in the RPM range which is what a street driver really wants.

 

If I get the 17 is it recommended that i get different spark plugs too? Anything else that needs to be done?

 

I would not change the crank pulley unless upgrading to either a 2005-06 oem crank pulley, ATI super Damper, or FluidGel Vibration Damper. These are all dampened as opposed to the Alta or Cravenspeed which are not dampened and can wear out your crank bearings.

 

1 heat range colder spark plugs and smaller supercharger belt, I believe it it is NAPA belt 539(?) if I remember correctly.

Edit: Can't go wrong with Way's Pulley Package, also includes a tensioner stop in case the belt ever breaks, this prevents everything from flying apart. A $20 part that could save you $600. http://www.waymotorworks.com/wmw-pulley-package.html

 

just got the 17% today, what should be done to keep it maintained well besides always having coolant and oil?

 

Keep an eye on your belt for a while just to make sure that all is lined up well. If that is good, swap the belt at least once a year. Other than that, have fun!

 

Regular mantance......
Cooler sparkplugs....the jcw ones would be a good thing....that and a new 535 length belt yearly.....and only buy the highest octance fuel you can get at the local gas station.
Enjoy!!
I had the same worries and fears as you....in the end I liked the power so much I kept on modding......amazing how such a small item can make such a change....the 17 is perfect for non revhappy drivers imo!

 

also i noticed when i step on the gas my car hesitates, what can be the cause of this

 

On a warmer day from a stop, heat soak...you may be feeling when the bypass valve closes, and the motor goes from normaly asperated (just above idle) to boosted....
Some cars had software updates to fix it....but some had issues, some did not...called the yoyo...
Sparkplugs can cause the hesitation....jcw plugs...are usually suggested with a pulley. They are one step cooler than stock s plugs....and should be changed just like as on a jcw...every service event...about 30,000 miles.