177 Tension Spring
 

Pulled my engines for a freshening, this thing has not been treated nicely!
Anyway one of the repairs I had to do on the Weiand 177 Supercharger was to weld up the hole for the tension spring, no problem done
My question is, there is a thicker cast area just beside where the bolt was originally installed, does anyone think there would be a problem with moving the bolt towards the thicker part. It would apply more tension to the spring by about 30 degrees
Thanks Jason
https://cimg1.ibsrv.net/gimg/www.off...7bf9612b62.jpg

You could always use a torque wrench to measure how much additional torque will be on the idler arm at +30* preload. That will also allow you to see if it can actually be preloaded by 30* more without binding on the snout. Any more tension in the idler will add heat to the snout and case, so that is something to consider beyond if the bearing can handle it.

That's a great idea, I will try it
Thanks

Then you can figure out how much load is on the bearing and see what kind of room you have to work with at 14000rpm. Here is the bearing number.
SKF 6304 for the snout bearing

BT

Thanks for the info!
That's going to refresh my math skills!

weight x moment arm (length of idler) = torque. You'll have to solve for weight. Whatever rpm you spin your engine to x 2 will be the max rpm of the bearing iirc. Good luck.

Ok so my results are
using my current belt, with the retaining bolt in the proposed location the increased fatigue load on the bearing would be increased by 59% to a load of .212kN the bearing is rated for .333kN
The spring does not approach a bind situation but I don't like the idea of increasing the load that much so, I'll keep it in the original location
Thank you BT for your help

Glad to help and I agree with your conclusion.

BT