Back to my jackshaft pulley story!
I was just about to take the jackshaft apart again, and decided to check out some dimensions, since Rich has been so good to send them up! Turns out that they were all very very close! Over all length was just slightly different, but not too bad! So, I decided to play around with the pulley and see where I was... What I was up against was what you saw in the pictures a couple posts up, where the pulley stuck out too far unless I removed the spacers, which put the hub of the pulley into the seal of the bearing, as the pulley has a recess vs a protrusion.... It also has two holes drilled in it for set screws...told you this was an industrial pulley!!! If I cut the protrusion down to fit, I think it would cut into the set screw areas, so it either all comes off and I make a bigger spacer, OR, I do the RIGHT thing and get a pulley that is closer to the stock one!
Here are a couple shots of Rich's pulley!
Here's what I figure happened many moons ago...about 1974 or so... When the third owner installed the Boss 302, they raised the engine frame mounts to allow the headers to clear the frame rails! When they raised them 1.5" this raised the original 6" diameter pulley into the body just below the cabin rear window! SO, they grabbed their industrial A/C supply catalog and ordered up a 4.5" pulley and cut it to fit..... Where the original is now, is anybody's guess, but I will tell you it WAS in Fresno....back then. (Still have not found the third owner.....who did all this work!) I did find the 4th owner and the jackshaft bracket and an air cleaner, but he didn't offer up any pulleys....I guess I could call and check anyway, but I think all he got from the salesman was an extra unused piston....!
So tonite, instead of working on stuff, I surfed and learned all about grey cast iron, ductile cast iron, maximum distance per minute of pulley travel....and that the internet is full of all sorts of crap!
Grey iron will work well up to about 4000rpms, ductile iron up to 6500. I believe these are continuous operational numbers, and that they would flash higher....but not 100% on that.... Ductile iron has more nodular metal in it, like cranks and rods.... Blocks and stationary stuff is made from the grey iron which has more graphite in it.... Told you...!
So, I just may contact a pulley manufacturer and see what it would take to cut one out of some billet steel.......Give them the dimensions and let them roll..... not sure if my dad would take this one on!!! We'll see!!!
Here is one last shot for tonight. There was talk of "allen headed nuts" and such before, used in retaining the jackshaft bracket to the engine. Here is a shot of one of Rich's fasteners....appears to be made from a 12mm diam socket head cap screw, that was drilled and tapped for 5/16"-18 about 3/4" deep! It is meant to be used with a double sided stud, as was used on the intake's center 4 holes (Two on each side) in the stock config from Ford. He says that they do not fit tight into the bores of the holes in the bracket, so there is still room for the bracket to move around a bit. They do not act as locators...
I thought it was a pretty neat deal! Have some pic's from another crazy Goose owner that came up with a rather novel aproach at this whole deal too!!! Will post later....
Out!
Steve
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