Pushrod comparisons

I am glad to see someone actually engineering something for diesel performance.

a few things to note, comparing critical buclking load on columns made of steel is strictly based on geometry, not the alloy (All steel alloys have the same Modulus of Elasticity of 30,000,000 psi in tension, and 38% in of that in shear)

Yes, a pushrod made of either 1018 or 4340 will work EXACTLY THE SAME!!! Given they are dimensionaly identical.

This is why when I held an "performance pushrod" in my hand and noticed it was smaller in diameter and lighter than the stocker...I opted to stay with the stocker.
 
So not only do my high performance pushrods fill with oil, which adds mass to the push rod moving up and down, but they are just repacked gasser pushrods that don't even have the right size ball in the end...:bang

And if what Diesel Freak said above is true, then they may actually be weaker than stock pushrods (since they look slightly thinner)...

Zach, do you have a trade up program on push rods as well? :poke:

I'd post a picture of my pushrods next to some stockers, but that would show someone's website on the side of the pushrod which would give away who made them...
 
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OD and wall thickness are the two critical dimensions as they should all be the same length.
 
This is a really good thread with lots of good engineering and information! So I have a question, if mass on the pushrod side is not particularly a concern would there be any reason not to just get your 7/16"ers as oppose to the 3/8"ers on a street rig?
 
:nopics:


PHOTOSHOP!!!!! PAINT!!!!

Here you go...

pushrods.jpg
 
mountaineer- our pushrods remain as a fuse, just are more rigid during operation. The 7/16 are not so much a fuse if your cam or gear breaks you will wipe out valves among other things" bad things" competition only. Check this gear and 3/8 .095 out failed at 5200r's I think, P7100 with lots of parasitic draw. Sidenote: (fixed gear and changed P.R.) HD cam, along with factory valves were fine.
http://i240.photobucket.com/albums/ff203/zacheryhamilton/DSC01267.jpg

got torque -thanks for keepin it clean and not turning this into a bashing forum i am trying to keep HD's section of the forums Information first, B.S. second. And yes I will trade you a set of HD P.R. for those. It will be $60 to cover shipping, shirt and hat, and to cover time to clean and inspect old ones.

muddin dude see above 7/16 vs. 3/8. 7/16 are geared more for competition for a few reasons. Mass is always critical in a reciprocating assembly! However on the low ratio(less linear travel) side of the p.r. there are more benefits to running better p.r. than not. 7/16 are hardass p.r's with well over 4000lbs of buckling force! 3/8 is what I would run on the street.


Thanks,
Zach Hamilton
 
We already talked about a price on you installing springs for me...PM me a price to throw a set of pushrods in it while I'm there please.
 
mountaineer- our pushrods remain as a fuse, just are more rigid during operation. The 7/16 are not so much a fuse if your cam or gear breaks you will wipe out valves among other things" bad things" competition only. Check this gear and 3/8 .095 out failed at 5200r's I think, P7100 with lots of parasitic draw. Sidenote: (fixed gear and changed P.R.) HD cam, along with factory valves were fine.
http://i240.photobucket.com/albums/ff203/zacheryhamilton/DSC01267.jpg

Thanks,
Zach Hamilton


So i was rereading this thread to freshen uup on my Pushrod knowledge and i dont seem to remeber seeing this post Zach,

It catches my eye because i have a Cam gear that looks EXACTLY like that one and i could not figure out why it happend

Here is the thread that i made about it in 2006.....

Broke the truck again

Skim through it please and tell me what you think.


Michael
 
I could only read the first post Michael. The one that broke at my shop was due to overreving I believe. There was nothing else wrong. After changing the gear and the pushrods the truck ran fine. I have also seen this happen due to lack of lubrication or contaminates entering between the cam and the block. Could you post more specifics about that engines pump,rpm, and use.

thanks
 
I could only read the first post Michael. The one that broke at my shop was due to overreving I believe. There was nothing else wrong. After changing the gear and the pushrods the truck ran fine. I have also seen this happen due to lack of lubrication or contaminates entering between the cam and the block. Could you post more specifics about that engines pump,rpm, and use.

thanks

At that time it was mostly a Street truck that pulled at local fairs....

215,191's 4GSK,60LB springs (Just in the Exhaust)

Ill see what i can do to make it so you can read/see the whole thing :bang
 
And to keep you on your toes.....

Whats your opinion on these...
Push rod measures .377
they weigh 3.7 ounces each or 104.89 grams

Pushrods003.jpg

Pushrods004.jpg

Pushrods005.jpg
 
That damage looks like some I have seen before caused by big rpm with a big pump. How many cc's was it flowing and how many R's? The valvetrain looks like it was unstable because of the piston to valve contact. which springs were you running?

That looks like a good pushrod, basic 3/8 with pressed in ends, and either a 3/8 end or a 10mm end(.393"). Do you know what the wall thickness is?
Zach
 
That damage looks like some I have seen before caused by big rpm with a big pump. How many cc's was it flowing and how many R's? I ran 4K RPM and I never had the pump on a benchThe valvetrain looks like it was unstable because of the piston to valve contact. which springs were you running?
Cummins 60LB Exh. springs

That looks like a good pushrod, basic 3/8 with pressed in ends, and either a 3/8 end or a 10mm end(.393"). Do you know what the wall thickness is?
Zach

I dont know the wall thickness :bang
 
Zach,

Have you dyno tested these on a 500+ hp truck (back to back without any other changes.)


I'm just shy of 700 hp, and I picked up a set of your pushrods last year. I haven't put them in because I convinced myself that they wouldn't really make a difference.

If you don't have dyno comparisons, I could possibly do back to back (before/after) dyno on a dynojet 248.

-jp
 
I dont know the wall thickness :bang
Did they come with the cam? If they did they are like mine .125 wall. I have bent rockers, snaped bridges, snaped rocker shafts and the push rods are still straight as can be.
 
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