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Old 11-11-2025, 08:06 PM
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unruhjonny unruhjonny is offline
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Thanks for replying Tom;
I seem to recall being in other discussions where I was scoffed at for proposing to "cheap out" by not buying aftermarket rods.

Seeing as my car is still a ways off from completion, I am trying to contain 'project creep' by setting a goal in my own mind's eye;
That goal has been to qualify for PSMCD - and I believe that an aftermarket rod is immediate disqualification.

Now, am I willing to disqualify myself from PSMCD for insurance against an expensive engine rebuild(?) - probably.

I will admit that although my engine (744 cammed 70-YZ) did see north of 5,800rpm on several occasion's - it sure didn't live up there... and prior to the scoffing I received here, I had no one give me cause to think that a reconditioned rod was a liability.

... ok I'll end my derail right there.

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2009 Cobalt SS: 13.9 @ 103mph (current DD; makes something north of 300hp & 350ft/lbs)
  #2  
Old 11-12-2025, 06:13 AM
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Formulajones Formulajones is offline
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Quote:
Originally Posted by unruhjonny View Post
Thanks for replying Tom;
I seem to recall being in other discussions where I was scoffed at for proposing to "cheap out" by not buying aftermarket rods.

Seeing as my car is still a ways off from completion, I am trying to contain 'project creep' by setting a goal in my own mind's eye;
That goal has been to qualify for PSMCD - and I believe that an aftermarket rod is immediate disqualification.

Now, am I willing to disqualify myself from PSMCD for insurance against an expensive engine rebuild(?) - probably.

I will admit that although my engine (744 cammed 70-YZ) did see north of 5,800rpm on several occasion's - it sure didn't live up there... and prior to the scoffing I received here, I had no one give me cause to think that a reconditioned rod was a liability.

... ok I'll end my derail right there.
No an aftermarket rod does not disqualify you from the pure stock drags. In fact they encourage it. After 50-60 years you can't expect all those cars to be out there running factory rods. A good aftermarket rod is cheap safe insurance and many won't even take the chance with reconditioned stock rods and possibly tearing up their ride and/or oiling down the track

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Old 11-12-2025, 08:05 AM
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Jay S Jay S is offline
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Maybe Dennis will comment on what light weight internals are forbidden in the rules for PSMCD. H beam rods are considerably lighter than a I beam rod, while they might be a little beyond the scope of the rules for pure stock, most H beams rods are not light enough I would call them light weight. They would be on the edge of what becomes light weight. A stock cast rod is right under 900 grams and a H beam is closer to 680 grams. The old early rubber rods were in between those numbers. Aftermarket RPM and Eagle 5140 alloy I beam rods are considered a stock type service replacement rod. For most of the pure stock classes I know of you can also use lighter weight pistons with 1/16” rings. But lightened cranks, strokers, different length rods, aluminum rods, and pistons with narrower that 1/16” ring would all be outlawed in pure stock.

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Old 11-12-2025, 11:06 AM
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I've talked to Dennis about this years ago, where I got that info from. He welcomes aftermarket rods purely for the safety reasons.

As far as saving a few hundred grams with rods I seriously doubt it's providing any measurable performance difference. I'm sure they've discussed that and why it became a legal upgrade.

Pistons on the other hand, there is HP to be found there so that's more of a controversial subject.

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