I wasn't necisarily looking to do this for more boost, I already figured I was maxed out as far as that goes. I was more interested in it changing the power curb. As it was on my dyno tune, I didn't see greater than 7#'s of boost until beyond 5000 RPM.

If I could attain 7#'s of boost at say 3500 RPM, and max boost at 6000 RPM, that would be more benefitial to me, giving me more power down low, instead of everything just up top.

 

Call 911,

You have the sdce setup for your crank pulley don't you? I mean you have the ATI damper and the machined spacer. How do you like it? I have a little wobble to my crank pulley and I was wondering if I should buy his setup? I was also considering this damper and getting a local shop to machine the spacer.

http://cgi.ebay.com/ebaymotors/PRO-D...spagenameZWDVW

 

Thats pretty much exactly what I did. I had to have my motor shop machine me a spacer to make it all work. It was an expensive ordeal, but it runs very smoothly, and I like it.

 

Do you have the ATI damper or the Pro Damper? Does your tensioner move up and down much while the car is idling?

 

Tensioner doesn't seem to move at all, but I am sure it's working since I got no belt slippage on the almost 600 RWHP dyno tune I did last summer with only an 8 ribbed belt.

I have the ATI Super Dampner.

Back to the original question, anyone know what eactly changing the crank pulley will do here for me?

 

Like others have said, it's going to over-spin the blower. You will need to put a larger pulley on the blower, to get it back to where it will be maxed out at 6000, if that's where you want to shift at. You will get more boost sooner. That will, in effect, move the power curve to the left on the graph (more power, sooner).

 

Josh, what size blower pulley will I need to change to? How much do the two pullies cost? And finally, will I need a new belt with this change? Or can I just change the tensioner?

 

Use the formula I posted to determine the pully combo you would need. If your shooting for 6000 use a combo that maxes at 6200 as you will exceed 6k from time to time on accident I'm sure.

 

If you kept your 3.40 pulley, you would max out the blower at 5900. If you stepped up to the 3.70, you could spin the motor to 6400 and max out the blower. I would recommend the 3.70. You would need a 43" belt for either of these pulley setups.

 

Thanks for all the info.

Josh, if I go this route, I'll let you know.