The 2.5" pulley worked for me on the 1.6L compressor without too much slippage. I didn't have a problem under power, it was the deceleration I always had issues with where the tension would bottom out trying to slow down the supercharger.
That pulley didn't work AT ALL on the 2.3L compressor. Way too much slippage. The first day I had it on it burned through the belt. If you think about it, the larger compressor was doing more work and needed more torque and I was making more boost. The smallest pulley that would run reliably on the 2.3: compressor was 2.7/8". I didn't have a 2.3/4" pulley to ever try out; that might have worked also. I did try running a 2.5/8" pulley - that one didn't work mostly due to how worn down it was. Whipple pulleys are anodized aluminum and they deteriorate rapidly once the anodizing begins to chip unfortunately.
If anybody's got access to a nice machine shop full of high-dollar machinery (HOWARD!) make yourself a STEEL pulley. That will grip the belt better and last forever. I am unsure why Whipple sticks with the aluminum pulleys.

yeah I've got a buddy with a full machine shop, I've thought about having him duplicate my 2 3/4" pulley out of billit stainless steel, but I don't know what that would cost him. he kinda helps me out on these projects on the side and I don't wanna take up all his time.

there was also a company I talked to that could make them, but it was fairly expensive IIRC.

Been thinking about that James.
I'll get one of the machinists (we have 2 now...and both are VERY good) to copy the 2 1/8 when it arrives out of stainless 'shaft' steel.

so, I'm here at work and doing some research on meth injection setups, anyone have experience with the brand 'coolingmist' http://www.coolingmist.com/? theyre controllers seem to be pretty nice, very very user controlable and programable against various different inputs, you can have it injecto based on boost, any 5v source (MAF, MAP, TP%, etc), even a combination of them, plus you can have their display show things like pump duty cycle, or fluid flow rate, which is nice since I already have a boost gauge. and it looks good too, even matches my cluster and blue LED's and Stereo blue LCD display.

still researching, but I like their setup, so far I think they're the front runner. devil's own and alkycool is definantly still in the running though.

Wow! I just watched one of coolingmist how-to vids and have to say I'm impressed.

CrazyHoe wrote:

Wow! I just watched one of coolingmist how-to vids and have to say I'm impressed.

yeah I've been reading up a bit tonight. I've read some reviews on other forums of guys who switched out from other meth kits like snow and had nothing but good to say about the coolingmist setup. cool thing is, I can splice it into my regular MAP 5V signal, which the PCM uses (which I trust more than my boost gauge MAP sensor), I also wonder if the flow sensor puts out a 5V output? if so I could splice into that and log the methanol flow in EFILive. plus with the 52mm controller, I can just put it in a regular gauge pod instead of trying to make something mount and look good in the dash.