When **** hits the fan

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1Fast340 said:
Stuff like this sucks and hope the remains of this gets put togheter soon making even better power :)

Not here to bash on hyper pistons or the op but i must say i much prefer forged since they will take alitle more abuse when the operator is doing the wrong things before catastrophic failure occurs.
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I really agree with you, one has to realize I when they're at that level with a build. Hyperutectic..while can work and handle some abuse...DO NOT tolerate detonation.

Sucks that you cant hear with Helmut on very well, I've clacked/pinged that motor once before for half a second. I heard it loud 'just once' when I dumped it in 3rd... I just let off in a blink and went to change the tune which was take it from 30 to 28 locked and Chevron 91 with stp or Lucas octane boost and that was the trick.
It kept it from clacking and run on... made it work perf where I live.
 
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nm9stheham said:
BTW, MO, is that oil deposits on the back of that valve in post #4, or just up gas deposits? Just wonderin' if there was oil in the chambers contributing to this too.
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Okay.
I'm glad somebody finally asked. I'm more so waiting for your questions , interesting.. The picture of the bowl near exhaust you will see deposit buildup under the valvejob. What that is is a slight tiny speed bump dip where the Harden seat met the head. So..1st guess the bump made idle reversion... 2nd That it was catching garbage that's in our gas and any oil residue that made it past the guide and or seal. The valves all have it.. so I'd flip the order of guesses.. lol objective thinking on the loose...eh....anyhow to that one port...I have one blue viton Manley stem seal on it that does a poorer job than the ones Brian put on 'black viton' when he touched up the valve job. So If it leaks oil down the guide well... you answer that one.. but I will tell you all who run a pcv valve to pull your heads and have a look sometime, have your awe moment ;) oh but yeah...I left that very tiny little dip bump because I had the magic number I needed at the time. I've since removed it and might toss it on the bench.. but probably not.
Gasoline is garbage these days, to say the least
 
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OK, so that may have been crud due to the poor seat/valve seal and the hot gases coming back. Seems logical. I was just wondering of some oil made it into the chambers and helped the detonation fun begin.

Those piston tops sure look 'clean' around the edges. Is that normal for this engine?
 
Man I sure am sorry about all that. btw, that port work looks familiar. I know a guy that can do that. lol
 
nm9stheham said:
OK, so that may have been crud due to the poor seat/valve seal and the hot gases coming back. Seems logical. I was just wondering of some oil made it into the chambers and helped the detonation fun begin.

Those piston tops sure look 'clean' around the edges. Is that normal for this engine?
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Yes, normal...lol...
No one else runs these and no one yet is posting any pics of a 8k mile run build that had coolant and oil blow through it after a piston disintegrated
The burn is central, it's a dish, fuel comes round that way from the int port, all I did was wipe the coolant with shop towels before taking the pic... some tan was wiped but that's air fuel path following the cylinder wall...thats how it works... the air follows or it breaks up and diminishes. Like a guide.

Carbon build up, it affects us all.
 
That sucks, i'm kind of thinking your engine is slightly too hairy for hypers... 6200 RPM with a 4" stroke is pushing it for piston speed, throw a little detonation in there and POP!

I broke a 360 with KB hypers as well, had too much compression for the small cam and pinged it to death; ran for 25k miles though. It finally broke a ring land, seized the wrist pin and cracked a cylinder which flooded the pan with coolant, but it still ran! Kind of even still had some balls to it too, ignoring the awful racket it made.
 
Port work and seats look nice from what I can see. Definitely asked too much from those pistons. I truly believe the piston speed/ rod ratio/angle and all the other dynamics with a 4" stroke worked to produce the perfect "storm". I've popped the tops off of hyper-u's but never filled the pan with gravel like I have seen. What are the plans for the rebuild? J.Rob
 
MOPAROFFICIAL said:
MoparOfficial sounds cooler than SafetyOfficial, lol, but I am safe at the least.
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thanks for not being insulted by my first post, I should have known better then to assume the stands werent there, it was definitely a first thought gut reaction post
 
MOPEkidD-3 said:
That sucks, i'm kind of thinking your engine is slightly too hairy for hypers... 6200 RPM with a 4" stroke is pushing it for piston speed, throw a little detonation in there and POP!

I broke a 360 with KB hypers as well, had too much compression for the small cam and pinged it to death; ran for 25k miles though. It finally broke a ring land, seized the wrist pin and cracked a cylinder which flooded the pan with coolant, but it still ran! Kind of even still had some balls to it too, ignoring the awful racket it made.
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I routinely rev'd to 6500-6800 rpm.
I beleive the hypers will handle the rpms, just not the user error as you mentioned. Lol
 
Agreed, been there as well. No problems.
The Hyper slugs do not like detonation at all.
After that fact, there fine.
 
RAMM said:
Port work and seats look nice from what I can see. Definitely asked too much from those pistons. I truly believe the piston speed/ rod ratio/angle and all the other dynamics with a 4" stroke worked to produce the perfect "storm". I've popped the tops off of hyper-u's but never filled the pan with gravel like I have seen. What are the plans for the rebuild? J.Rob
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Cam reground same, good grind imo
have the 45's touched
New intake valves because that was the last facing they could take.
Pondering diamond 51405's with a better 1008 .039 gasket "used 8553pt previously"
Have a another 1978 std block in the shop getting the same 'all mains studded', line honed, .030 over this time and main galleys matched to old block ,oiling was bitchin, or basically open them up to the right size.
I will also measure and get a geometry kit from b3racing, been meaning to but havent.

Its a pickle ... I have 60 cc Iron head chambers with shallow side that's. 030 deep, I actually opened it to that because it was dean near closed and I had quenchers sitting flush with a compressed .046 8553 gasket that I had already milled and setup.
Changing pistons is now a task.
Zero deck pistons a plenty... but I'll end up with no quench an almost or about 10.1
Custom pistons...maybe, that's ex$pen$ive.
Maybe I can machine some to a d cup..or machine some of the cup down 2 cc or so.

Easy and risky way... 356's again, open the quench .008 to .038 quench and set the rings the same or .002 more gap and then go buy a wideband.lol.

Objectively thinking here..
It's hard to decide. What if the cylinder just widowed and that's what happened...
Then nothing changes except the bore size or incorporate a sonic test. If this was professional racing, competition... I would would really need to know exactly what happened in order to correct and make the most of this what I feel is an excellent winning combo. It's not average but it's not breakthrough, it's just calculated.
 
MOPAROFFICIAL said:
Cam reground same, good grind imo
have the 45's touched
New intake valves because that was the last facing they could take.
Pondering diamond 51405's with a better 1008 .039 gasket "used 8553pt previously"
Have a another 1978 std block in the shop getting the same 'all mains studded', line honed, .030 over this time and main galleys matched to old block ,oiling was bitchin, or basically open them up to the right size.
I will also measure and get a geometry kit from b3racing, been meaning to but havent.

Its a pickle ... I have 60 cc Iron head chambers with shallow side that's. 030 deep, I actually opened it to that because it was dean near closed and I had quenchers sitting flush with a compressed .046 8553 gasket that I had already milled and setup.
Changing pistons is now a task.
Zero deck pistons a plenty... but I'll end up with no quench an almost or about 10.1
Custom pistons...maybe, that's ex$pen$ive.
Maybe I can machine some to a d cup..or machine some of the cup down 2 cc or so.

Easy and risky way... 356's again, open the quench .008 to .038 quench and set the rings the same or .002 more gap and then go buy a wideband.lol.

Objectively thinking here..
It's hard to decide. What if the cylinder just widowed and that's what happened...
Then nothing changes except the bore size or incorporate a sonic test. If this was professional racing, competition... I would would really need to know exactly what happened in order to correct and make the most of this what I feel is an excellent winning combo. It's not average but it's not breakthrough, it's just calculated.
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Deck the block a bit with .027 Cometics to get the quench gap with zero Deck forged above the new deck height?
 
BTW, looking over your CR numbers, the 8.9 DCR and 185 cranking pressure, and cam durations don't seem to work out with 10:1 SCR. I came up with 11.3 SCR with a 11 cc net dish+quench pad, zero decked and 60 cc heads (that would include the .030" deep flat area), and that is compatible with the cam, cranking pressure, and DCR up at your altitudes. (I just like to see if all the numbers come together on these things...)
 
No.5 upper rod bearing tell tale... detonation.
Blew piston ,wiped out the cylinder wall, bent the rod, windage tray, pan a tad... but the windage tray caught the brunt of the scattering....the rod hits the top of the bore and jammed it up if the chunk in the intermediate gear didnt....crank is tits, 6 pistons survived, one in bits... the other ...skirt broke off. Rubble in the pan, all the carnage you love to see just because it's interesting and rarely shared. Yeah I know... "where's the upper bearing shell ?" Well it's in the timing cover and I thought I snapped a pic but I didnt... so I'll go the garage in the morning and snap one of the upper no.5 rod bearing into copper. The 2 valves are junk... just the slightest, they were hung open from debris blowing through and spun 'tell was the roller wear marks were slanted while all others were in line front to back. More pics on the way.

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Holy cow! That motor sure did blow up! That's one of the most impressive engine failures I've seen/heard of. Thanks for all the detailed pics and story! Good attitude too, not many people would be so glad about a motor fragged that bad. Also, I had no idea cylinder walls were that thin! I always thought they were way thicker.
 
Chained_360 said:
Holy cow! That motor sure did blow up! That's one of the most impressive engine failures I've seen/heard of. Thanks for all the detailed pics and story! Good attitude too, not many people would be so glad about a motor fragged that bad. Also, I had no idea cylinder walls were that thin! I always thought they were way thicker.
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If you for some reason need to see worse carnage have a look at tractorpulling,they know how to blow stuff up bigtime.


Back on topic,those are some tough rods you have there..
 
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