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AIR FLOW PISTON

I have re-evaluated, and I think Wild is right. I think I would try to find a different way to get it home. Friend with a pickup that can rent a tow dolly?
 
I have re-evaluated, and I think Wild is right. I think I would try to find a different way to get it home. Friend with a pickup that can rent a tow dolly?

Gotta admit, my first thought was drive it too.. But then thought about how many engines I've seen damage from one cylinder take out multiple other cylinders... And if a piston break like hypers have been known to do.. Now you've potentially destroyed the block.... Tow it...
 
1st thank you for the great reply. You're correct on the KB. I have 2 more questions this morning. I'm 200 miles from home and will haven't seen head gaskets on shortly. Can I drive it? Are pistons replaced only by complete set. I'm going to sell the car. Physically can't keep doing this. Not going to do this blindly; buyer will know. Thank you all very much.
Most piston suppliers sell '1sies' but not sure about that with the KB's and no, not a good idea to drive it. Still not sure of the broken piston piece didn't make it's way up into the intake to make ruin of other cylinders. I've seen engines where someone 'lost' a small part like a nut from an air cleaner and instead of looking for it until it was found, they just got another and well, one engine had damage in more than one hole. Also, since you have one ring gap too small, what are the other's like in the other 7 holes? Like mentioned already, that engine needs to be pulled apart to do a good checking out and I mean check everything including the springs on the heads, bearings...uh everything.
 
It might be a little closer but not much, the thing is it has an open space just below the top ring that acts as a heat dam, trapping the heat in the piston head and around the top ring... The ring can survive if given enough end gap but if treated like a normal cast piston the ring ends will butt together & the ring will stick in the bore.. When the rod tries to pull the piston back down the bore the ring sticks & part of the ring land typically breaks off.... Which is exactly what happened with the O/P's engine...

And yes, cast typically will take a small shot of nitrous.... Just don't get to aggressive..
Thanks for your help. You are a good man to know. You've responded to other questions from me.
 
Thanks for your help. You are a good man to know. You've responded to other questions from me.

Thanks, there are allot of guys here that try to help... It's a tough situation, on the road with a hurt engine... Hate to see you compound the problem by trying to nurse it home.... Sucks that it happened but trust me, you aren't the first.... It the block in the car original? If so you really don't want to risk hurting it.... Not that I'd want to risk hurting a non numbers block but I'd be sick if a car had survived 50 years with it's original engine & I damaged it trying to nurse it home...
 
I zoomed in on the pic and there are a lot of scars right where the plug rests. Do you know if PV clearance was checked?
If the walls are not hurt you can buy a single KB piston. Unfortunately they dont cast or stamp the size on them, they only have the series 236 or what ever on them so you will need to mic it.
 
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Even if you have to rent a truck and trailer, I would not drive it like that. If you have luck like me, it would end up coming apart and take out a cylinder or two. End up having to sleeve the block, replace a head, etc.
 
And I don't really get what the love affair is with those hypereutectic pistons. Yeah, they are 'supposed' to be stronger than standard cast pistons and not as good as a forged one and priced accordingly but what good does it do to have the top ring so close to the head of the piston and then you need to gap them wider because of it? Is it supposed to create a better ring seal?
I’m with you. I like traditional cast, or forged. Hyperpathetics always seem to get in trouble.
 
Most piston suppliers sell '1sies' but not sure about that with the KB's and no, not a good idea to drive it. Still not sure of the broken piston piece didn't make it's way up into the intake to make ruin of other cylinders. I've seen engines where someone 'lost' a small part like a nut from an air cleaner and instead of looking for it until it was found, they just got another and well, one engine had damage in more than one hole. Also, since you have one ring gap too small, what are the other's like in the other 7 holes? Like mentioned already, that engine needs to be pulled apart to do a good checking out and I mean check everything including the springs on the heads, bearings...uh everything.
I'm pulling heads and replacing head gaskets. Had hoped to drive it home but not sure now. Will check head on left carefully. Not in other. Thank you very much for your help. Wish you and yours a great Christmas.
 
I'm pulling heads and replacing head gaskets. Had hoped to drive it home but not sure now. Will check head on left carefully. Not in other. Thank you very much for your help. Wish you and yours a great Christmas.
Hope there's no damage anywhere else and Merry Christmas to you and yours too!
 
Hypereutectic pistons are not a bad piston. Dad says, "You just have to be smarter than a slug of aluminum and you have to be able to read instructions."
 
Hypereutectic pistons are not a bad piston. Dad says, "You just have to be smarter than a slug of aluminum and you have to be able to read instructions."
Yup....but seems to be, a regular cast and/or a forged piston is harder to screw up with :) More forgiving I guess....? And how many figure buying a ring pack for a hyper piston require file fitting the rings? Most just figure it's no big deal. You're right though, gotta read the destructions.
 
In this case, the pistons were in the motor when bought and I knew nothing about them until you guys taught me. I don't recall buying or installing rings. Don't know if rings would have some info about extra gap .
 
KB requires .0065 x bore w/ minimum .026 for top ring and .004 for second ring for NA gap.
http://enginepro.com/downloads/kb_installation.pdf

Screenshot_20211223-211134.png
 
We’ve never broke the top of a KB. Built an 11 second street 340 with them. Years ago. It’s still running. I would not run that engine with the piston damaged. You’re just asking for more cost in repair and additional damage.
Doug
 
We’ve never broke the top of a KB. Built an 11 second street 340 with them. Years ago. It’s still running. I would not run that engine with the piston damaged. You’re just asking for more cost in repair and additional damage.
Doug
Thanks. Decided my luck is not up to the task. I will come back with a trailer soon. That is a killer picture / car by the way.
 
Hope there's no damage anywhere else and Merry Christmas to you and yours too!
As a follow up, if you will, I did not find the metal piece in the other head or intake but did find another plug with collapsed electrode. Is there anywhere that you suggest I look? Thanks again.
 
If you can do the work yourself, the penalty shouldn't be too bad.
I would yank the motor, replace the piston, open the ring gap, and reassemble. New gaskets, and you are on your way.
If you have to have all that labor done..... yeah it'll be a bite on the wallet.
 
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