I have a 496 13 to 1 cr that runs 6600 on the motor and 7200 on NOS and has been good for two years so far.


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AHH Dude! You just jinxed yourself. 

No disrespect, but those engines didn't scatter because they were 496s.

Well I'd like to know what caused it because the 468 I'm running now makes the same power and turns a little  more rpm and has lasted 5 years with the occasional150 bottle tap. Both 496's had less than a year on them with no bottle and nothing has changed on the car except the motor.


But I wouldn't take a stock 454 and go straight to a 496, if step up as needed like I said earlier to get the most out of the motor. But me personally, I'll never run a 496 again, bad juju for me.

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No disrespect, but those engines didn't scatter because they were 496s.

Joe you could not be more on point.


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I am really not a fan of boring OE blocks to the extreme.  The cylinder walls flex too much, even with a "filled" block.

A siamesed bore bowtie or aftermarket block is much better suited to larger bores.

Once you hit that 4.375 and larger bore diameter, the heads really start working well.  I would never go there on an OE block though.

To answer your questions flusher


Well...  Who built the 496?  The 468?

Jerry goodhall, he was a family friend who built all my grandfathers boat and drag car engines in the 80's and 90's. His work is something I would never question or doubt.

 Was there a post mortem done on the 496?  If so, what were the results?

First block split the crank at 4/5 and windowed the block, second time around I don't think there was really a way to find out what caused it but there were 2 broken rods, windowed 1/3 cylinders,cracked the block at #2 split the crank in 2 spots, bent the cam and munched a few pistons on valves.

Just thinking, assuming the tune was right...  Most strokers that I have seen use a Scat or Eagle crankshaft, and the vast majority use a cast steel crank.  Some even use cast iron.  As GT pointed out, those are better suited for tow trucks and not performance applications.  The longer the stroke, the less overlap exists between the rod and main journals, the more that crankshaft is going to flex.  Castings don't like to flex.

Internals were scat if I remember correctly and the 468 that's still alive are eagle.

 Was it internally balanced?  External balanced cranks flex more than internally balanced cranks because the because the counter weights on the damper and flywheel are not supported on both sides by a bearing.  What kind of damper did it have and was it in good condition?

The each rotating assembly's  were balanced pretty damn close and a new balancer and flex plate were used on each motor. He said the motors were good to 8k but all the head work and cam profile were set up for 2500-7k. The block was suppose to be over built for the operating range we were aiming for and the valve springs were a little heavy for the cam,to prevent floating and rings were gapped for bottle use.

What about oiling?  How did the bearings look?

Couldn't tell ya.

You didn't mention the pistons.  Did a piston break?  Were they cast or forged?

Forged and yah there were some cracks and breaks both times.

What about the rods?

They came with the cranks if I remember correctly so skat cranks with skat rods and eagle crank with eagle rods in the living motor.

What about the main caps?
Don't know what brand but they were both 4 bolt caps and I don't remember which one but one of the blocks had the outer bolts at an angle.


If I have to sweep up all the little pieces of my life's savings, I would want to know what went wrong. 

Well you and me both but I was fortunate enough to only have to pay labor on the 3rd motor.
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Here is a picture of a block with the clearance cut out for a 496.


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