360 rebuild issues

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Thanks for the help guys. I needed that to get me going after machine shop. For some reason I thought my concerns were unfounded and that they knew better than me. Just half ***'n it IMO. Got a couple 10% summit codes if anybody wants. They expire 3/13/14. PM me, don't post pls.
 
Next possible issue - Will I have to rebalance with +20 or +30 pistons? You would think that would be something a person could find on the net. Looking at the Sealed Power slugs. Or another stock replacement piston for no $200 balancing.
 
The only way to know for sure is to see what they (new pistons & pins) weigh compaired to the stock pistons & pins. If off by a few grams (1-5) i wouldnt sweat it unless yer gonna buzz the heck out of it then go nat's a$$ on ballence,otherwise a few grams will be fine for stock o/h. But also remember lighter is better! Free hp!
 
The gram weight of the pistons,get heavier. The new pistons,add weight,up top. This would effect,the bob weight at the crank. If they screwed up,they should re-balance for free,J.M.H.O. Hopefully ,others respond.
 
The KB pistons that replaced the stockers in my old 71 340 were alot lighter than the stockers. Had to drill holes in the counterweight to compensate.
 
Before you rebore the block, check out that hole/defect. Was it from wear or machining damage? If it is a sand pocket, casting defect will the boring clean it up.
 
Thats kinda what I thought, I was hoping replacement pistons would keep the OE weight. Was trying to look up piston weights but can't find much. He has agreed to bore & hone since the honing didn't take care of it and get me the correct bearings so if all goes well seems like we would be even. Guess we'll have to talk about it.
 
3406pk said:
Before you rebore the block, check out that hole/defect. Was it from wear or machining damage? If it is a sand pocket, casting defect will the boring clean it up.
Click to expand...
Looks like pitting to me. Like maybe moisture collected there. Think the block sat in some guys shed / garage for a number of years before I got it. I can only hope it will fix it. I think you can only bore up to +30 on a magnum block due to thinner walls. Payed $50 for the short block. Spent a ton more now! Oh well :dontknow:
 
you may want to find a competent machinist. If they cant even handle a hohning job, I would not let them bore my stuff. food for thought, If they screw up again you may be looking for a block rather than advice.
 
Agreed, but why would I take it somewhere else if they will fix it for free? Dropped it off yesterday and told them exactly what I wanted and expected from them. He said a lot of people bring there stuff in and want just enough to get it running and thats it, and since I told him I didn't want to spend a bunch of money, (engine kit + work $1000 was a qoute) he thought I was one of those people. I think I'm back on track now.
 
Just a FYI; 2stroke engines have holes in the cylinder walls, hundreds of times bigger than that,and all over the place and across from each-other,etc, and they dont break rings or wear rings because of them. IMHO, on an econo-street build, a little divot/surface blemish (that little half-inch long one)would be a non-issue.Now about those other lines in the pic; the shadow-line just above the top of the piston,the one that looks like a reflection,I cant comment. And that long curvy line;whats that about? Anyway I see you have made your decisions.Jus saying.
 
Surface oil and reflection. Just don't want any loose ends. I hear what you are saying and is the same thing the machinist was saying.
 
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