97stanger

I'm currently running an IW 10% overdrive crank pulley, 8 rib setup, Thump tensioner and 2.85 blower pulley and see roughly 19-20psi. I can get a good deal on an 18% overdrive crank pulley. I am still running my '97 timing cover. I have done some research on the 18% overdrive and am seeing different answers/results. Does anybody run this piece first hand and what type of modifications had to be made? Is it a must to run an electric water pump? I'm also considering going with the 2.7 blower pulley if I swap to the 18% overdrive and I can imagine I would pick up another 5psi minimum with some decent power gains. Just looking for some input on those of you who know/have installed the IW 18% overdrive crank pulley. Thanks guys

97stanger

ttt, anybody have experience?

uberstang1

I can tell ya for sure an 18% od crank pulley wouldn't fit on my car with my water pump or my crankshaft sensor, I had to grind off some of it for the 10%, an 18% i wouldn't be able to grind without ruining the cover, this is on a 3 bolt 97 cobra timing cover though.Thats a small blower pulley, thats the one thing about the vortechs is the lower step up ratio causing to run smaller blower pulleys and fighting with belt slip.

TCStangerv6

I told you already. You don't need to run an electric water pump.
here is my 18% on m car. All I did was lathe some of the lips off the water pump at work.
as for the crank shaft sensor. I grind some of that off too. This was on a 3 bolt tensioner cover. I'll get pictures of that later. Everything works fine on my car.