Quote Originally Posted by rspears View Post
Don,
No disrespect intended, but I've read and re-read your long post above (#245 with the pulley pictures), and I'm totally confused. Without rehashing all of the ratios, curves, mandrel sizes and who did what to whom at one time or another in this saga are you saying that you were running a 3.5" main drive pulley on your crankshaft, driving a smaller 67mm (~2 5/8") alternator pulley (the gold anodized one with the ruler) when you were chasing this problem? Like 36sedan, I'd say that the shop that did that work has some incompetent people that are being allowed to make decisions, and if they're in the BBB listing you should file a complaint. You also mention a 94mm (~3 3/4") pulley, which I assume is the second black pulley from Jones, but you're not running that one, right, due to space constraints?
Quote Originally Posted by Don Shillady View Post
Roger, the 94 mm dimension refers to the overall diameter of the small alternator which fortunately is one of the higher rated 69 amp versions rather than the mini 55 amp variety. The Moroso mount is curved to hold this maximum diameter alternator and no more. As such I can barely close the hood as per requirements from my wife that the car can't show the (chrome trimmed) engine! The smaller pulley in the picture was the 2.375" Jones alternator pulley which would have given 11% more increase in alternator rpm but it has an offset in the back that would not fit available space. A test run from Ashland to Bowling Green and back today showed that on the road at 60 mph the alternator produced 14 volts or slightly above and only fluctuated slightly due to the internal regulator on the rear of the unit. The little traffic light driving showed that the voltage occasionally dropped to 13 volts but remained as a charging voltage at a 950 engine rpm idle. Today I sent the unused pulley back to Jones for credit. Not shown is the 1.125" diameter keyed mandrel bolted to the harmonic balancer along with thick aluminum spacer washers that serve as a backing to the 5" pulley to keep it from potential wobble. The mandrel provides a snout to move the 5" pulley forward to align the fan belt. Apparently Drag Racers use such a mandrel pulley system to drive a fuel pump and other accessories and was familiar to Bruce Orlandi who runs a 706 cu. in. aluminum BBC in a fiberglass Cavalier.

Henry and 36sedan,

I picked that shop because the owner has a Chevy sedan with a Corvette engine on a 700R4 but I sure wish I had found Bruce Orlandi's Performance Transmission shop first! Bruce has a one man shop that is extremely neat and is experienced building his own funny car. That would have saved a lot of frustration!

Don Shillady
Retired Scientist/teen rodder
.....and I still have no idea what you were running before....

Would you mind some focused questions, requiring short, succinct answers?
1)
.....are you saying that you were running a 3.5" main drive pulley on your crankshaft, driving a smaller 67mm (~2 5/8") alternator pulley (the gold anodized one with the ruler) when you were chasing this problem?
Yes, or No.

2) If "No", what size pulleys were you running "before", and what size are you running now? Crank pulley size before - ___________ Crank pulley size now - ____________

and, what size alternator pulley were you running "before", and what size are you running now? Alt pulley size before - ___________ Alt pulley size now - _________

Again, no disrespect intended Don, but you're throwing so many numbers around with so much extraneous information that I simply cannot tell what's what. Regarding the alternator, you're saying that the overall diameter of the alternator is less then 4"? That's TINY!!