Swapping pushrods with a different motor?

[Randy Bush]

Is there a such thing as a 350 without valve-train wear? Lol


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Nope. When I use to rebuild those where two things that got replaced a lot.

 

[Frstdiesel]

How much longer? A bit longer (thousandths of an inch longer) or much longer (1/4 + inch)?

I just got the time to measure and there is .042 difference in length. The e-bay pushrods are longer than my original 6.9 pushrods.
That's why I was wondering if the ratio was the same. If the ratio is the same I will run my original pushrods.
Like I said I got these off of e-bay and the seller said they were off of a 7.3, so who really knows.

 

[Randy Bush]

I just got the time to measure and there is .042 difference in length. The e-bay pushrods are longer than my original 6.9 pushrods.
That's why I was wondering if the ratio was the same. If the ratio is the same I will run my original pushrods.
Like I said I got these off of e-bay and the seller said they were off of a 7.3, so who really knows.

I don't know if for the 6.9/ 7.3 but for a lot of engines you can buy over and under sized pushrods so after head work or such the lifter plunger can be centered in the lifter. This may be the case with the E-bay ones.

 

[Macrobb]

Also on 7.3 and probably 6.9s the oil pressure valve in the filter head causes problems too.

Not really; typically, it sticks open, resulting in hot-idle PSI of around 10-12. Which seems low... but International thought that was within limits(Service limit for hot idle PSI is 10 IIRC).
And, I've run multiple engines like that for years with seemingly no ill effects - Oil gets pumped through the lifters mostly due to the cam squishing them anyway, so pressure doesn't (really) matter there... The bearings seem to do OK as long as they have a flow of oil, and of course you have the piston squirters which just spray plenty of oil; lower pressure might be an issue here, but you aren't usually running full load at idle.