I have 4 OD installs belonging to customers running around the freeways of So Cal using the Bosch type relays. Some have been in service for several years and no problems. I have the original GM unit on my truck and find virtually no difference in the performance. As mentioned the originals are in excess of $100, the Bosch type are cheap and/or free at pick your part. Something that hasn't been mentioned in the quest to "go faster" is that the brakes and steering were about as good as the original 50 mph top speed allowed. Something to think about.
Fred

Last edited by rfs56trk; 01/28/2010 6:07 AM.
1956 3100 Pickup/Red/350/3sp OD/PS/Disc Brakes
1957 Bel Air Sport Coupe/Red/355/TH350/PS/Disc Brakes
2017 Silverado LT Single Cab SB/Black/5.3/6 Speed Trans
1947 Willys CJ2A w/F-Head engine