Hello every one. This is my first post. I've been lurking for a while. This is a great site with a lot of Good info. I've already learned a lot of useful info here.

Ok. I'll start this by telling everyone where I'm starting from. I purchased an 87 camaro with a 2.8 v6 and 700r 4 tranny. I purchased this with the intentions of rebuilding it and installing a carbed 350 and a t-5. A couple of months after that I bought an 85 z28 with a ( 350) and a 700 r 4. Turns out its not a 350 at all. It's a 327. Which doesn't bother me because I have always liked them. Anyway I was told from the guy I purchased the z28 from that he had bought the car around 8 yrs ago. He had purchased the engine which had been rebuilt by some one that he knew and installed it in the car but had never finished the car. He said he ran out of money and then lost interest in the car and lost the title as well. So it was a pretty good buy at 400$. The car was out of time and barely wired well enough to run. I timed it up and it seemed to run pretty well so I pulled it out of the car and began tearing it down. In the beginning I just wanted to make sure it had been rebuilt which from the looks of things it had been. At least everything looked like it. New gaskets everything was clean and so on. I was just going to go ahead and put it in the other car until I ran the numbers on the heads and they came back as 305 heads with only 1.84/1.50 valves. So I decided those had to go. So I figured why it was down that far I might as well re ring it and put in new rod and crank bearings in.

Here's where my problems started. I started pulling the pistons and 6 out of the 8 top compression rings were broke in half. Directly across from the gap. It wasn't carboned up where they were broken it almost looked like it just happened. The pistons slid out fairly easy just by pushing with my fingers. The ridge didnt seem to be very bad either. The cylinders aren't scarred up. So what caused this. Did the rings seize from not being ran and when he started it they broke? Is there another problem? Do I need to bore the engine? I really don't want to because of money issues. Im not real familiar with rebuilding engines so any help would be highly appreciated. It also has flat top pistons.

I already have to get the crank turned. I found grooves in a couple of the rod and crank bearings. I need to keep the cost at a minimum. Again any help would be appreciated. Thanks

Also feel free to move this post if its in the wrong place

 

i over rev'd my 305 and broke 10 rings. not sure if it was cuz of over reving or lack of fuel at high rpm

 

Some guys don't check the ring gap and that breaks the rings.Not a bad thing to add .002 to the ring's gap.

 

Someone told me that the cylinders could be egg shaped. Is this a possible cause?

 

It was the ridge.

Think about how the ridge was formed. The previous rings slowly wore against the bore, and the bore against the rings. The top edge of the rings will become slightly rounded in this process, as will the bottom of the ridge. New rings have sharp top edges. This sharp edge was being jammed up against the slightly rounded ridges by the pistons, putting the rings between a rock and a hard place. New rod bearings will also increase this likelihood, as a worn upper bearing half will not push the piston as far up the bore as new bearings will.

It doesn't take much ridge to do this. If you are installing new rings without boring the cylinders to the next oversize, all ridge has to be completely removed. Or, you'll break the new rings. If the bore wear isn't excessive, you can remove the ridge, break the cylinder wall glaze, and rering it.

Insufficient ring gap is more likely to break the piston than the ring.

About the heads - what casting #? The 416 or 601 305 heads are superior to pretty much anything that the factory put on 327's (that the restorers haven't gobbled up). 1.94/1.60" valves with basic bowl clean-up will let them wail on a 327.

 

Thanks guys.

5_7_ kid. That makes a lot of sense about the rings. As for the heads I have 3 sets to choose from. I'll get the casting numbers and post them as soon as I can. I know I have one set with 1.94 valves. I think theyre 76 cc though. They're off of a crate motor