I opened it up completely for cleaning, and Pulley Boys are out of the 2.2" and 2.0" pulleys until next month. I'm hoping by some miracle my SCPerformance pulley gets here in the meantime, since it'* paid for

If it doesn't get here by then, I'll probably go with the 2" from PB, since I've got my cooling working much better now. Heat was the main reason I didn't want to go that low in diameter. I'm still going to do some pulley diameter calculations vs. SC rpms. See where I fall in the heat range. With an intercooler, the 2" would be a no-brainer for 92/93 M62'*.

The intercooler causes some interesting problems with the fuel rail being able to reach the lower intake manifold. Hector is working on another idea for me that would solve this problem. For once, he'* not giving my the scoop on it. I have an idea how he'* planning this, and I have a couple more ideas myself, on in the design stages already. There should be some interesting SC and Intercooler ideas coming around this year that would benefit both the M62 and M90. Cross your fingers, hold your breath

I'm gonna hold on the pulley, but I'm willing to bet you Floz gets their pulleys from PB. That'* probably why PB is out of stock right now. I may even ask Brian at PB for a custom pulley based on my research into heat and rpm'*. Even if I don't, and the SCperformance pulley never arrives, PB will get my business. Brian has been bending over backwards for us already. I can't wait for the chance to get up there and meet him, as well as getting a peek at his operation. I'm gonna try to sucker him into joining our NW meet in Seattle.

http://www.zzperformance.com/zzp/inf...stat_holes.htm

Then there'* this:
http://ca.autos.yahoo.com/maintain/coolant_answer8.html

Drilling the holes has a similar effect. Drilling a 180 may cause it to act like a 160. Besides Emissions, it can cause problems with TCC lockup, and other temperature critical funcitons on your car. It can also take longer to get heat from the climate control.

I drilled 4 holes in my thermostat yesterday. The car ran just below 180° for 20 miles in 45° ambient air. In other words, had it been freezing, my car might not have ever warmed up. I'm lucky I used 1/8" holes (four of them), and not any bigger. In colder climates, I'd suggest 1/16" holes, or maybe 3/32". Having my car run cooler benefits my intake temps, especially since I'm SC, and come summer, I'll be damn glad I did it, but I can tell you if I lived in a colder climate, what I did yesterday would have screwed me. Looks like I got lucky and did it perfectly. My car runs about 10° cooler above 50mph now. At idle, the temps can still climb. This will be of very little benefit in that situation.



Just make sure you start small, and de-burr the holes. I also suggest starting with a thermostat that has a stainless steel body, like mine. No chance for corrosion by exposing plated metal that way. Also make sure you rinse the thermostat very well to get any metal shavings out before re-installing.

Drilling a 160 thermostat would be suicide. Even running an unmodified 160 is questionable. Most only do it if their car spends alot of time at the track. If you run either the 160, or drill a 195 or 180, you do it at your own risk. My main reason for doing it was to dissipate as much heat as I could before I went to a smaller SC pulley. Smaller pulleys generate more heat, both from compressing the air, and from spinning faster (mechanical heat).

WARNING
I just did another test run with Jseabert driving, and me on the scantool. I'm averaging 169° at 55mph, in OD, with no heater on. That'* too cold. Ambient was 50°, with an IAT of 62°.

I'm going to make another thermostat with 1/16" holes and try again. My bet is that I'll be running two 1/16" and two 1/8" holes when I'm done. Just a guess. Now imagine the ambient temps right now where YOU live. See the problem? When I turn my heater on Auto/90°, my temps drop to 160%Blub/drillstat.JPG[/img]

Just make sure you start small, and de-burr the holes. I also suggest starting with a thermostat that has a stainless steel body, like mine. No chance for corrosion by exposing plated metal that way. Also make sure you rinse the thermostat very well to get any metal shavings out before re-installing.

Drilling a 160 thermostat would be suicide. Even running an unmodified 160 is questionable. Most only do it if their car spends alot of time at the track. If you run either the 160, or drill a 195 or 180, you do it at your own risk. My main reason for doing it was to dissipate as much heat as I could before I went to a smaller SC pulley. Smaller pulleys generate more heat, both from compressing the air, and from spinning faster (mechanical heat).

WARNING
I just did another test run with Jseabert driving, and me on the scantool. I'm averaging 169° at 55mph, in OD, with no heater on. That'* too cold. Ambient was 50°, with an IAT of 62°.

I'm going to make another thermostat with 1/16" holes and try again. My bet is that I'll be running two 1/16" and two 1/8" holes when I'm done. Just a guess. Now imagine the ambient temps right now where YOU live. See the problem? When I turn my heater on Auto/90°, my temps drop to 160°. Way bad. If you live in a cold climate, don't drill any larger than four 1/16" holes. Not unless this is strictly a 'strip' car.

I figured that'* where Floz was getting them! I'll wait for now. See what SCperformance does. Go check out my M62 teardown pics.