I'm buying a SC pulley this weekend from ALTA. (Alta headquarters is 30 minutes from my house.) My car is just over 100,000 miles so people have advised just doing the 15% reduction. I'm still feeling a pull toward the 17%. Is it a bad idea to go with the 17%? My car has been well maintained all it's life. What kind of wear can I expect from the 17%. So I just need a little peer pressure I guess on my decision. Thanks
A 15% is all you really need on a motor that old / young. 15% is good and reliable size. You can also make lots of power with just a 15% ...see below.:ihih::ihih:
I would stick to the 15%. The 17% is going to overdrive the S/C at medium to high RPM and you already have 100K on that S/C, why ask for trouble. Before installing I'd do a compression test. At 100k the engine might be getting a bit tired. It's cheap insurance that there is nothing terribly wrong with it now before stressing it a bit more.
Nate is right on there!! YES you WILL see a better low to mid range over the 15% with the 17% pulley, but if you put two cars together , one with 15.. and the other 17% it will be the difference in the drivers, not the pulley, that that is in front. And the 17% will generate more Heat, causing the ECU to remove ign timing and fatten up the fuel when the knock sensor goes nutz!! Testing of pulleys has show the 17% will allow more power than the 15%, but the ecu will usually KILL that increase when detonation is increased. Some have gone all the way back to a 11% to kill the add'l heat and actually keep the power. Just saying........................... Thumper PS: look into a water meth system to make it all happy!!
FWIW - I agree with all of the above for cars with a manual transmission. On cars with the automatic, the 17% is a better choice, as the auto limits the car to lower revs (6700 and below) and the 17% will yield more low-rev torque which helps the auto considerably. I've run both and wish I had started with the 17%. I assume you have a manual, but just covering all the bases here.
Or you could reverse engineer think about it. My 03, original supercharger with 100,000 miles on the 17% pulley I bought from Helix years ago. It still runs like a scalded cat @ 130,000 miles.
I agree with Kellen. I've installed almost 500 pulleys and would love for you to buy our WMW pulley, but if your looking for someone close. I would go with the Craven pulley over the Alta.
Imo, choose the pulley sized based up how you will drive, and the most common octane in your area.... in the northeastern us, we have 93/94 at the pump ...so the 17 is fine for a non redline driver .... In other areas, not having 93/94 might mean the extra temp of the pulley might result less power at times....so a 15% or even jcw equivlent might be better...again depening on how you drive, and where...no hard and fast rules, but more info on you planned use beyond miles would be useful. the total miles...not so important...you either have good compression, or you don't... Hech the sc could be worn out...know your boost?! It is a bit of a wear item..... but folks run it till it fails...usually the waterpump gears.....
Sorry Kellen, I should've stopped by and picked up the craven pulley. I did end up going with a 15% pulley from Alta. I will be sure to make my next purchases from Craven and WMW. Now that the uncomfortable apologies are over with here is my update. I did the install myself. I got of work at 6:30 AM Saturday. I made the 40 minute drive to Alta and picked up my stuff. I purchased the 15% pulley, new smaller belt, tensioner stop, MSD coil pack, spark plugs, and wires. Got back to my part of town and pulled into my friends garage I was borrowing. Note: by the time I started the install I had been up for about... 20 hours. Install should not have been too difficult but I think the lack of sleep was playing tricks with my head because when I went to release the tensioner after installing the new belt I was unable to notice I had routed the belt WRONG! Thankful I had the tensioner stop I felt it was a good time to go to bed. I got a ride home at 1AM Sunday. 34 hours awake is not the way to do car work. Next day me and a friend found my mistake and quickly corrected it. Oh and so everybody knows my spark plugs were in desperate need of a change. Here are some numbers with everything said and done. Boost: Stock= ~10-11psi 15%= ~15-16psi Mileage: Old plugs= ~23mpg New plugs= ~30mpg I don't have any 0-60 times or HP numbers yet but I'm sure those will come at some point. I can say tat the car is a ton of fun and I plan on taking good care of her. Like I said earlier I will be sure to head out to Craven real soon Kellen. Perhaps we can talk suspension... Thanks to everyone for the advice. I will be sure to tap into the wealth of knowledge you have provided again sometime soon.