DTM with Power Pulley

BajaT4 · Post by **BajaT4** » Sun Sep 10, 2006 8:36 pm

Jake,

Have you done any testing with the DTM using a power pulley? I've read some articles that say there isn't much loss to cooling efficiency and others that say there isn't much of a HP gain. My goal is actually neither. I just want my fan to turn at a different RPM to get rid of the the annoying harmonic I've had for the longest time. I don't remember if it was there from the start, but I have traced it back to the fan.

I went to the extent of using silicone inside the shroud to try to smooth out the rough transitions between the air deflectors and shroud. I also changed the fan position back to the factory 2mm specs. I just find it hard to believe that I have 2 bad fans that both create a noise that I have never heard on any of the Type 1 based vehicles I have owned. Help!

thanks

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Mon Sep 11, 2006 6:10 am

Yes.
You can expect a 15% loss of cooling on the head temps and 20% on the oil with about a 5HP power gain for an engine operating under 6K RPM- higher revvers see more benefit.