I'm rebuilding a 1990 305 TPI engine, right now it head-less so I can port and polish them. The crank is at 0* TDC #1 piston all the way to the top. I installed the a new timing chain, put the timing cover on. When I went to install the new hamonic balancer I noticed something wrong right away. The timing line on the balancer was in the middle. My old one(balancer) lines up pefectly with the timing cover. The timing marks are on the right hand side of the cover, so it's at the 2 o'clock position.

The parts store guy said I was running a 350 balancer on a 305. It is skinnier than the 305's. The engine ran good, no engine vibrations.

Should I recheck my timing chain and why is the balancer different on a 305 when everything but the pistons are interchageable?

 

GM only lists one part number for 305 and 350 balancers for 1990. I also looked it up at NAPA's web site and they also list one part number for 305 and 350's. I would go back and ask the parts store guy if he knows what he is talking about.
Also maybe you should post this question under the tech/ general engine forum.

 

So I can use a 350 balancer? If so, cool. Where can I get that info, DerekKraese?

 

I would still make sure you have the correct part. You can go and look at Napa online to find the part number. I will Post the GM part # on friday I have to look it up again. But I think 87/ 88 - 92 V8's list the same balancer for 305's and 350's.

 

Both engines used a neutral balanced HB, so it really doesn't make a great deal of difference.