Keyed Crank...What is it?

[BYT U L8R]

After all the supercharger talk I was looking into some of the "problems" with different systems put there. There is a lot of talk about keying the crank for high boost applications. Isn't the crank already keyed for the balancer?
Does a separate key-way need to be made or is the existing key-way made more robust for the balancer.
Just want to know what I'm in for down the road...Oh, BTW if one has to key the crank can it be done without removal of the crank and be done with use of a guide bit over the end of the crank.
Thanks and regards.

 

[Martin D]

The balancer is pressed on. It is an interference fit.

Take it from someone who knows(me)- spinning the balancer is a VERY bad thing. To the tune of 15 bent Valves.....

As for keying it in the car...IF you are creative, it can be done. I would still prefer to do it removes!

Regards,

 

[Mike Brunton]

Martin,

How did a slipped balancer cause bent valves? It's my understanding that the balancer serves the purpose of damping the vibrations of individual cylinder fires from the pistons, and eases stress from crank twist. I know turning it isn't good, but the crank and cam (and hence valves) are kept in sync due to the timing chain - so just trying to figure out how a spun balancer caused it... did it set up a vibration in the motor that caused a problem? Or was it something like the balancer/pulley spun and allowed the motor to way over-rev?

Thanks for the info bud,
Mike

 

[Martin D]

Mike,

Thanks for calling me on that. As I dig back into my memory banks, I did determine that I called it wrong. I bent the Valves when my Cam pin sheared. Sorry about that. I have had the motor apart several times. They seem to all run together.

Some of the negative things that happened when I spun the Balacer was - The car started to run VERY hot. And, the Balancer did a pretty good job scraping up the end of the Crank. We were ok. But I guess the worst thing that can happen is you can eat up the end of the Crank and end up needing a new one.

I stand corrected. Thanks Mike!

Regards,

 

[Mike Brunton]

Martin,

Thanks for the info... I didn't mean to "call you out" or anything - I was just curious as to what happened... just as likely that I had a misinformed idea of what the balancer was like on the Viper.

I'm glad you didn't get bitten too bad by your problem. Sheared cam pin? Dayum, that's even worse! I hope you're *ahem* 'enjoying' your car appropriately to cause these problems!

 

[1TONY1]

Does the crank not even have a key way....The f-body LT-1 engine has a key way in the crank but none in the balancer. Simple fix: have a key way put in the balancer and install with key. I'm guessing neither one are that way on a Viper???