Smoky Joe

Missing the point -

unless the heads were so bad that several valves were really leaking and the engine lacked any real power and they lost compression on more than a cylinder or two - the heads won't make a lick of difference in blowing an engine or burning oil unless mistakes were made. 

Improving the heads won't destroy anything down below. IF it was weak after, it was weak before and tossing a rod was pure coincidence and nothing more unless, like I say, the heads were SOOOO bad, the engine was performing very poorly. 
That 340 was going to blow -  and in this case it wasn't even a valve job - it was totally DIFFERENT heads, so no comparison at all.  

 There's nothing about a good valve job where the tech CLEANS up after themselves that will make a bottom end weaker or fail faster. 
The driver does that. Not the valve job. 
Being a lead foot after a valve job won't matter either - again, unless there was horrible compression loss. If it goes, it was going to. You don't have to baby them or drive them any different. Decades of experience have proven that (as well as my training)

Putting higher compression parts on isn't the fault of the heads nor the valve job.
And it's really unrelated to doing valve jobs - this was a case of performance heads on a lower end ready to blow any time in any case - head swap or not. 

A valve job wouldn't bump compression that much unless the valves were REALLY REALLY BAD, then the engine was in bad shape anyway.
 It's like a person with plugged arteries -  like fixing one artery and letting the others go and the person has a heart attack - the fix didn't cause the problem, the lack of fixing caused the problem. 

There is no real relationship between valve jobs and losing lower ends - other than the loose nut behind the wheel.
Don't walk around it or walk it back and say "depending on if they are a lead foot or not" - nothing to do with it. That's the driver, NOT THE VALVE JOB!

People over the years - and even here - blame it on "doing the heads and letting the rest go".
Nope, it's not the first part, it's the last part. It's not doing the heads that's the issue, it's letting the rest go.  But in reality - doing a valve job is no more risky than not - do the valve job. IF the lower end has troubles later it would have anyway. 
You will not cause trouble doing the valve job. There's no risk to it - no more than there was anyway even if you did NOT do the valve job. 

That's the bottom line - do not be afraid to pull heads and do valves and seats. You do NOT risk the lower end. The lower end will last just as long, or just as not long as it would head work or not. 

So don't let this BS about doing a valve job being risky stop you. IF the head needs work, get it done. 

I've done 'em for over 40 years on cars of all sorts - big block and small block Ford, Lincoln, Mercury, SBC, BBC, Mopar, Mopar highway patrol cars (talk about cars that get pushed hard!!!), 4s, 6s and 8s from the 1930s on up and more - including foreign makes, even tractor engines. Never has doing a valve job cause any issues later.  There's no reason for it to. Our college prof in engine design and theory, etc. said - well, can't say here what he said.

Ive done valve jobs myself.   And I clean clean clean.  Spotless is how I like them.  I use white paper towels..when they are clean....Im satisfied. The towels dont lie. Eyes do.  Ive had engines the used oil. And usually by the time it needs a valve job...the bottom end isnt much better off.  But thats been my observation and Ive also had some blown head gaskets and get hot....the engines dont like that either

Edited by purple72Gremlin - Aug/16/2019 at 11:59am

A month ago my suspension was that clean. Several wash tubs of warm water, a cup of Simple Green and scrubbed with a large terry cloth after a high-pressure wash... you could take a white rag and not get it dirty under that car. That includes the fuel tank, skid plates, axles, springs, wheels, steering knuckles, front spring supports, fender liners, drag link, etc. 

And when you take the car in for exhaust - the tech is really careful and you get the business owner coming out and sitting down and asking about the car.