Well tonight I had some time to kill and thought I would try out the new air compressor I just picked up last week.

So I went out to the garage and figured I would disassemble what was remaining of the original 350 shortblock. It would not only afford me the opportunity to try out some of my new air tools, but also see what the rings, bearing, etc looked like in the car. Remember the car was diagnosed with leaky rings, one up to 50% the rest all were leaking up to 20%. So I started ripping and tearing.

Pulled the pan to expose the connecting rods etc. I pulled the first piston #1 cylinder and to my surprise the upper ring came out in two pieces :eek:

I removed the rest of the pistons and ALL of the upper rings were snapped in two! :eek: The #7 cylinder was in about 15 pieces! I about crapped when I saw that.

The thing that still amazes me is that the engine was still able to hurdle that car through the 1/4 at 12.80 sec.

I know for a fact that the car has never had pinging with me driving ect on two occasions. 1 was I tried 87 octane gas, and it pinged under HEAVY acceleration. And the other time I purposesly advanced the distributer timing for experimenal testing. Both occasions I immediately left off the gas and did not induce it again. Neither of these cases were enough to do the damage present.

The only thing I can figure is the previous owner did something stupid with gas or the distributer and caused the damage. Ever since I got the car, the lower end power had been a bit lacking in my opinion. But I never owned a vette before to compare it too, nor did I have someone to compare SOTP feel too.

Guess I should have pulled all the piston the first time I had it apart to inspect and change out the bearings. Guess you live and learn. Now its all history now anyways. :lol: This new 406 should be a real shocker to me! I just can't wait to feel the power from this thing. :D

Well thought I would let you know what I found, since I have been quiet lately with the rebuild. Its creeping along :thumbs:, with Hunting season and then the holidays, we decided to just give it some time. It should be back together in the next month or so.

Oh yeah, the air tools/compressor worked great too.
:cheers:


[Modified by ski_dwn_it, 6:27 PM 12/8/2002]

 

:cheers: Glad you got to use your new toy

 

Just curious,what was your oil consumption like before you tore this motor down?

 

Jesse,
Just wondering, was there any ridge at the top of the cylinder at all? How were the second compression rings? The reason why I'm asking is this past summer I had a 350 that I was rebuilding for a guy that had been rebuilt a year ago. He also suffered a lot of cylinmder leakdown so he brought it over for me to freshen The thing came apart just like your, every top compression ring was broken, and all of the second rings as well as the oil rings were perfect. There was just the slightest ridge at the top of the cylinder. The previous rebuilder must have thought that the little bit of ridge should not be a problem, so he did not remove it. The new rings must have actually touched that ridge, probably at higher rpm as this is in a 4X4 sand racer, and broke. I'm not sure if yours has any ridge or not, but this could be a possability. He had no oil consumption problems, the oil rings were fine. Congrats on the new air compressor and air tools, must be nice to get Christmas early!! :lol: :cheers:

 

I was thinking 12.80 was a little high for that set up. :cheers:

 

Jesse

Just make sure your shoelaces are tight once you take a trip down the 1320 with that monster of an engine you're constructing :cool: :D

 

Shoe laces hell :eek: he better be wearing one of those jock straps :lol: :lol: :lol: or he may just leave something behind :lol:

Awesome set up you have there :smash: :smash: :smash:

 

Sinistervette,

As far as *I* know the engine is the stock engine...perhaps there was a problem from the factory with it. :confused: The engine only has ~50k miles on it now, so the damage must have happen early on. There is a slight ridge when you run your hand up the bore, maybe you are correct in the reason why. Perhaps just a bad batch of rings. Guess we will never know. :confused:

The second ring and the oil ring was fine. There was no combustion oil consumption, but after the engine started breathing better. I couldn't do anything to keep the oil from leaking out of the oil pan. Must have been due to all the blowby.

I am just gonna be so happy when this new one is in. I have been fighting with this setup for close to a year now. I agree with whoever said that the 12.8 is slow for this setup, but considering the condition of the rings it amazing it wasn't running mid 13 or 14s. Its just a shame I could see what it would have done....Oh well..time for bigger and better :thumbs:

I'll have to dig out my old jock from wrestling :lol:

 

Jesse, you are going to like your bigger motor.Glad to hear your air compressor and air tools worked out well. :cheers:

 

my stock engine was in the same boat. 4 cylinders had fractured top rings. just age, heat & everything else takes there toll on the poor things. i have cast hastings plasma moly rings now which are supose to resist fracturing much better but i wish i would have bought ductile. from what i hear it's even stronger.

 

Dude, you've got a wing. :(

 

YEAH! :boxing ........and I like it :D