Got a few question I couldnt find answered in a search...

First off I got a cog driven ATI procharger thats going to be pushing 15lbs. I snapped the nose of the crankshaft and am going all out on the rebuild. I got completely forged internals but need to get a better damper. BTW this is a 92 L98 350

1) Should I get a bigger damper or smaller? Im assuming the bigger because it will put more meat at the end of the crank and cause less vibration. Is this right?

2) If i get a bigger damper will I just need a different timing pointer or will I have to get a completely different timing chain cover?

3) Do I need to get the crank double keywayed or is that going overboard?

4) Im either going ATI or fluidamper. Anyone have a preference on why one is better than the other?

Please help so I dont make the same mistakes twice. :hail: :hail:

 

The size of the balancer won't affect much- the balancer isn't the thing that let go on you and it's vibration dampening deals with internal engine harmonics, not the tension and vibration from the blower drive system.

If you snapped the snout off the crank and are truly going "all out" I'd recommend switching to an aftermarket crank that uses a larger diameter snout. They're commonly referred to as "big block snout cranks" becuase they use a snout that is the same size as a big block Chevy, but everything inside is still small block dimensions.

I have never gotten into blowers enough to have these kind of problems so I can't advise you further, but you might want to look into this as you plan your build. Ask around with people who know and have actually done this.

 

Your sig says D1SC. At 15lbs you should never have had that problem. Did you happen to have a stock cast crank? As a matter of fact the cog belt doesn't get tightend as much as a Serp belt so it should put that much side stress on it. You should have your crank cut to blower specs while you have it out. ( that is a 1/4" keyway 180 degrees from the stock one. You can by a damper from ATI or fluidamper with this keyway in it. Your other crank must have had a loose center bolt, cast crank, or detonation to bust off the hub. Make sure you get a 4340 steel crank.

 

I agree

 

ouch!

 

I was running 10 lbs on a stock cast crank w/ the ribbed belts when the crank gave. I updated the sig because I got excited about my build. LOL.

I have a eagle 4340 crank thats going in the build and am now going to run the cog so hopefully I wont have this kind of problem again. Going to the machine shop pretty soon and will definetly take your advice. Cant get a bigger snout crank because I got the crank off ebay but will cut the crank to blower specs.

Thx guys:hail: