WTF

That makes 2 of us … I did love the 6-packs too :)
Going full mechanical on that setup with a hyper 440 under them, a 4 spd and an educated right foot, produced a huge fun-factor and a nice wailing sound that could be heard blocks away.

This thread has turned the corner onto Ho Street.
 
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I had old cars many years ago and knew that pinging noise. That is how we tuned our old 6 cylinder Vauxhalls. Top gear at 30mph WOT and if it pinged we would just trim it abit.
Never heard anything like it on this. The guys at HBR in Christchurch had it on their dyno and had no pinging there.

Was that piston jammed in the cylinder??
 
Going full mechanical on that setup with a hyper 440 under them, a 4 spd and an educated right foot, produced a huge fun-factor and a nice wailing sound that could be heard blocks away.

This thread has turned the corner onto Ho Street.
Imagine a thread could ever end up on Ho street!! :eek: :eek: :eek:

So, back on topic!! WTF! Hahahaha
 
On my own engine, the failure happened so fast there was no time for the obvious signs of detonation other than the tell-tale broken piston.

The spark plug looked fine but the electrode was tapped shut.

And there were small gobs of aluminum on the plug under magnification.

There were smaller pit-marks on the dome, which was from detonation.

The large piston-dome marks were from the piston fragment dancing around looking for an escape route. It did manage to find its way into the Cat when I was on the drive home from the track.
 

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Pic number two looks like a shot of something from space lol
 
On my own engine, the failure happened so fast there was no time for the obvious signs of detonation other than the tell-tale broken piston.

The spark plug looked fine but the electrode was tapped shut.

And there were small gobs of aluminum on the plug under magnification.

There were smaller pit-marks on the dome, which was from detonation.

The large piston-dome marks were from the piston fragment dancing around looking for an escape route. It did manage to find its way into the Cat when I was on the drive home from the track.
Is the 3rd pic the bad piston and rod .. looks like the rod is a new one ….
 
Going full mechanical on that setup with a hyper 440 under them, a 4 spd and an educated right foot, produced a huge fun-factor and a nice wailing sound that could be heard blocks away.

This thread has turned the corner onto Ho Street.
There s nothing like the sound of kicking in the outboard 500 cam secondaries on a six pack ,, I’ll,say more than a wailing sound hahaha . Mine was a 340 with a Holley 6-pack and vacuum secondaries that I modified with jets , springs , metering road and block ,, was externally adjustable without removing the float bowls .. the vacuum set up was more steerable and controlled IMO. My memory s intact lol , the primary was a 350 CFM AND EACH OUTBOARD CARBs WERE 500 cam .. The setup was a up was perfect for economy and full owner .. much better than the 650 and 780 Holley 4 barrels … with the Thermo Quad and the Hollies I was getting around mid 10’s MPG and at the time had a factory 323 ( memory ? ) rear gears single trac that I replaced with a pumpkin type rear from a challenger with 373 gears posi trac .. it had lots to of other mods also .. list was long .. but the MPG improved to right around 17 .. that in itself was surprising to say the least and the power was a lot more than stock .. SEAT OF THE PANTS !
The engine was a cast engine 1973 model and not the earlier forged higher compression model.
 
Pic number two looks like a shot of something from space lol
HaHaHa..Yes, it does.
The piston piece that broke out was trying to do a quick sketch of the Earth (flat version) before it was bitten in half by the Intake Valve.
The other half rocketed out past the Exhaust Valve (.700" Lift) possibly during Overlap, and was intercepted by the Substrate in the front Cat where it was apprehended a short time later.
 
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Is the 3rd pic the bad piston and rod .. looks like the rod is a new one ….
No, that is the Rod with the damaged piston that was removed from the engine, as is.

There was no other damage other than an Intake Valve that needed to be lapped to remove embedded Piston material on both the Valve and Valve Seat.

After the Piston popped and tripped the C.E. light due to a no-spark condition, I drove it home (at a reasonable rpm) because I was going to rebuild it anyway. In hindsight, it likely wasn't a good idea but whatever doesn't kill 'ya, makes you stronger they say. Fortunately, the Engine agreed and powered itself home without further incident.
 
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Just drive lightly until then. Just put forged internals and they are fine.
I really like the ZF 8 speed trans conversion. If I had the money I would do that. Be just like a Track Hawk. Fast and better on gas
Knock on wood (my head), I have 103K on mine, no issues other than the leaky PS lines. Did 115mph on the interstate coming to work this morning, with a smile I might add.
 
Knock on wood (my head), I have 103K on mine, no issues other than the leaky PS lines. Did 115mph on the interstate coming to work this morning, with a smile I might add.
Is that a Oak or Mahogany wood head hahaha
 
No, that is the Rod with the damaged piston that was removed from the engine, as is.

There was no other damage other than an Intake Valve that needed to be lapped to remove embedded Piston material on both the Valve and Valve Seat.

After the Piston popped and tripped the C.E. light due to a no-spark condition, I drove it home (at a reasonable rpm) because I was going to rebuild it anyway. In hindsight, it likely wasn't a good idea but whatever doesn't kill 'ya, makes you stronger they say. Fortunately, the Engine agreed and powered itself home without further incident.
Lucky without a doubt … it may have helped when the broken off piston peice escaped the combustion chamber ..
 
There s nothing like the sound of kicking in the outboard 500 cam secondaries on a six pack ,, I’ll,say more than a wailing sound hahaha . Mine was a 340 with a Holley 6-pack and vacuum secondaries that I modified with jets , springs , metering road and block ,, was externally adjustable without removing the float bowls .. the vacuum set up was more steerable and controlled IMO. My memory s intact lol , the primary was a 350 CFM AND EACH OUTBOARD CARBs WERE 500 cam .. The setup was a up was perfect for economy and full owner .. much better than the 650 and 780 Holley 4 barrels … with the Thermo Quad and the Hollies I was getting around mid 10’s MPG and at the time had a factory 323 ( memory ? ) rear gears single trac that I replaced with a pumpkin type rear from a challenger with 373 gears posi trac .. it had lots to of other mods also .. list was long .. but the MPG improved to right around 17 .. that in itself was surprising to say the least and the power was a lot more than stock .. SEAT OF THE PANTS !
The engine was a cast engine 1973 model and not the earlier forged higher compression model.
The Thermoquads had issues that were fixable. At the top of the list were the resin floats that, over time, absorbed gasoline and became rather heavy. Old school brass floats to the rescue! The second oops were the Secondaries that wouldn't open reliably. A short length of quality wire fixed that issue.

Those triple venturis on the primaries worked quite well and on the proper manifold, offered decent economy.
 
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If the Earth was round and spun at 1000 miles per hour (which it does) and you are traveling east on a jet at 999 miles per hour, you would never reach your destination. However if you were going the other way, you would reach your destination in no time.

Thought for the day. ;)
 
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