Stocker Crankshaft Heavy Metal

[Charles Rainey]

I have been away from Stock Elim motors for a while and I wanted to ask a question. I was in a very reputable engine shop early in this week and I saw something that I wasn't aware of. They were machining a Stock Eliminator motor and was adding heavy metal to the crankshaft. They were adding heavy metal thru the crankshaft side of the counterweight. I had always operated under the conception that it had to be hidden. Comments please
charles

[Dyno]

My guess is that the counterweights have been turned down and heavy metal had to be added to correct the balance. Dyno

[Mark Yacavone]

The rulebook says something about normal balancing.
If the pistons /rods/ rings are lighter than OEM, then the OD of the counterweights is the best place to take off the counter weight.
The competent shops know how much to remove without having to put it back on, if you get my drift...so be forewarned..

[Dinsdale]

An externally balanced motor like a 428 FE needs weight added to the rear crank counterweight to make it internally balanced. There are other examples as well. This is legal but you may have trouble with a light crank with added heavy metal being considered a "normal" balance job.

[Tom keedle]

sent a 66 289 out for an overhaul and balance (nothing special, just a stone stock rebuild)
as we don't do that at the shop and it came back with a swiss cheesed flexplate and mallory metal in the crank...
what's a "normal" balance job?

[Alan Roehrich]

In Stock Eliminator, it is legal to use heavy metal in the crankshaft in order to internally balance an externally balanced engine. Other than that, heavy metal is not legal, as it falls outside of the "normal balance job" rule.

[Mike Taylor 3601]

Tom,
The only way your 289 flexplate should have been drilled is if was previously a zero balance flexplate,like a 300 six.

You may have to fill in a previous hole in counterweight of crank but not with heavy metal.
Mike Taylor 3601

[Charles Rainey]

Originally Posted by Charles Rainey

I have been away from Stock Elim motors for a while and I wanted to ask a question. I was in a very reputable engine shop early in this week and I saw something that I wasn't aware of. They were machining a Stock Eliminator motor and was adding heavy metal to the crankshaft. They were adding heavy metal thru the crankshaft side of the counterweight. I had always operated under the conception that it had to be hidden. Comments please
charles

Let me re-clarify this , This was not a external convert to an internal. They were using a lighter crankshaft like a 305 and making it fit a 350. They were drilling and pressing the heavy weight into the side of the counterweight. In the older days, I was always under the impression that we had to install the weight and then we could weld it in and totally cover it so it could not be visibly seen that we had added heavy metal. Was I wrong in remembering that.
charles

[Jeff Lee]

which is why customers shouldn't be allowed to roam around the shop...

[Charles Rainey]

Originally Posted by Jeff Lee

which is why customers shouldn't be allowed to roam around the shop...

Jeff
Your comment is quite well received. Since the motor was for a very good friend of mine. I just thought he and I would like to know if the motor was going to be legal. apparently if you were doing the work for a customer, you would not want the customer to know if it was legal or not. It was just a question with no harm intent. I most certainly do not think you would be building me an engine that I could not see until NHRA got to look at.
charles