Engine Why do I keep snapping pushrods

Jcsports

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May 20, 2019
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So I have a 94 stang lightning block 5.8 swap Holley heads trickflow stage 3 cam pushing 500+ crank pushrods have been measured at the correct length runs fine after replacing pushrods valves are sealing so the pistons aren’t contacting the valves do I just need hardened pushrods for this amount of power? I just keep snapping the heads right off right around 6500 rpm
 
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Jcsports

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Get some hardened one piece pushrods from Trick Flow
 

HotFox

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Could be valve float or poor geometry? What rocker setup? Hydraulic roller? Lash? How long has it been together?
 

JmP6889928

You might slide out if you are going too fast.
May 18, 2019
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What kind of angle are the push rods at? Do you have guides in place too? You may be too tight on lash for that high of rpm.

Forgot to ask-are they oiling? Looks pretty dry.
 

Jcsports

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May 20, 2019
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Geometry seems right roller is right on the center of the valve hydro roller system I heard you need to check lash periodically on aggressive cams for these motors it’s been together a two years and I never touched it and it’s dry because I cleaned it with brake clean before the picture
 

Jcsports

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They’re not stock they’re aftermarket but they aren’t forged or anything part number is rp-3339 sealed power pushrods 5/16in by 7.572in
 

96pushrod

I think they're a little easier to get off
May 15, 2018
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They’re pretty much stock strength though. At any decent spring pressure it’s time to step up to hardened push rods. Trickflow makes chromoly ones for like $100
 

96pushrod

I think they're a little easier to get off
May 15, 2018
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Thought about it, any the don’t make tha length.


Those should work.
 

Jcsports

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May 20, 2019
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Perfect thanks dude!
Thought about it, any the don’t make tha length.


Those should work.
 

Jcsports

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May 20, 2019
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Anyone heard anything about periodically checking lash on these motors? If so how often and do you check it by just resetting it?
 

96pushrod

I think they're a little easier to get off
May 15, 2018
961
584
103
28
Savannah
Anyone heard anything about periodically checking lash on these motors? If so how often and do you check it by just resetting it?
Once you get a few heat cycles it’s not a bad idea to check preload. You running a hydraulic roller, correct?
They should stay pretty well adjusted.
 
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Jcsports

New Member
May 20, 2019
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I’m going to put a set of lifters in too just to make sure I don’t have any issues any suggestions?

Was thinking these
Once you get a few heat cycles it’s not a bad idea to check preload. You running a hydraulic roller, correct?
They should stay pretty well adjusted.
 

96pushrod

I think they're a little easier to get off
May 15, 2018
961
584
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Savannah
I’m sure they’ll work fine. In all honestly, the stock ones work good too. You were probably just bending/deflecting the push rods which made it seem like the lifter may have been having problems.
 

Jcsports

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May 20, 2019
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I’ve definitely got 1 collapsed lifter but the rod isn’t ruined on that cylinder so I’ve gotta do em anyway
I’m sure they’ll work fine. In all honestly, the stock ones work good too. You were probably just bending/deflecting the push rods which made it seem like the lifter may have been having problems.