Mopar guru's,I have a crank pulley mystery

I was swapping out the crank pulley on my 59 wagon with a 70-71 340 and I could only get 5 bolts to line up. One of the holes on the harmonic balancer is offset. I measured both crank pulleys and they had equal distance between bolt holes.I'm new to mopars and was thinking there might be a special crank pulley for this motor?

 

Are the pullys from a 360 different because of being an externally balanced engine? Just a thought....

 

the early mopar small blocks had one hole offset on the harmonic balancer. in the mid 70s they changed to an even spaced pattern.

 

I didn't think that a 59 would have an harmonic balancer. I ***ume that you're talking about a poly 318? I've got pulleys from both models and can check for you later today.

One thing I can guarantee,with those offset holes it will take you 5 goes to get it right!

Lots of little tricks with Mopars- keeps the not-so-serious players away from them and leaves them for the fanatics LOL

swifty

 

Why didn't you use the pulleys form the 360 ? I believe there was a difference between the 360 and a 318 poly .
Well if all but one bolt lines up and is centered correctly then drill a new 5th hole !

 

Thanks, straight axle tom,that's the answer I was looking for. Now I just need to find an early273 /318/340 crank pulley. It must have a 360 pulley on it now. Anyone got one?

 

if you can't find the right one slot one of the holes with a round file.

 

I just installed an aftermarket balancer on a 340..Had to file one hole oval so all six lined up..The new balancer instructions were very clear on this.
Early engines (pre 73 or so) had one offset hole. Later years were evenly spaced.
Dave

 

I was planning on grinding it out,just thought I'd ask about it here first,thanks for the advice.

 

I know the 440 source makes one for big blocks with a slotted hole supposed to fit all mopars. The flex plate converter only fit one way also the holes are not concentric.