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what happens if you miss a shift or over rev with hardend pushrods

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Old 03-29-2005, 05:16 PM
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Default what happens if you miss a shift or over rev with hardend pushrods

I know if you miss a shift or something with stock pushrods they will bend.But if you put in hardened rods and miss a shift,wont there be a lot more damage then just bent pushrods??
Old 03-29-2005, 05:54 PM
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Bend/break valves....crack pistons etc...
Old 03-29-2005, 05:59 PM
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I did it twice, and nothing happened!! It sounded real bad!!
Old 03-29-2005, 06:31 PM
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So If i plan on only installing a small cam (ls6 or similar)then i should probably just use the stock pushrods right?I mean I dont think i would need them unless i raised the rev limiter up over 6500 or put in a big cam and big springs.someone let me know what you think.I dont want to miss a shift and bent break valves and pistons when it can just bend the pushrods and and easy cheap fix.
Old 03-29-2005, 06:39 PM
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i think it's recomended that you get hardened pushrods regardless of the came you run. stockers are known to be weak and break very easily. it's better to be safe and spend $100 now then spend a lot more later
Old 03-29-2005, 07:08 PM
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I also would upgrade to a hardened pushrod.
Old 03-29-2005, 07:12 PM
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If you have the motor apart to install a cam..... why not go with a better pushrod too? Upgrading the valve springs is a nessassary thing, no matter what cam you go with... so why not do the pushrods too?
Old 03-29-2005, 07:14 PM
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still on my stock rods...and i have the custom comp 224/224 .581/.581 112LSA cam.....no problems yet...BUT on the other hand havent over revved OR missed a shift either....their not quiet as easy to break as people think....**** ur riskin more than ur rods anyway when shiftin over 6300
Old 03-29-2005, 08:05 PM
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u need to take the rocker arms off anyway, and the pushrods are right there please dont skimp on something so small and inexpensive.
Old 03-29-2005, 08:53 PM
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I dont think you guys understand what i am trying to say or ask.If i was to put hardend pushrods in while doing a small cam swap,ls6 cam for example,and then missed a shift and mechanically over-revved the engine.With the hardened pushrods being in there wont MORE damage take place.If i have the stock pushrods in and i over-rev the piston hits the valve forcing the pushrod or weakest and cheapest link to bend/break.With the hardened pushrods the piston hits the valve,the pushord does not bend but instead the valve goes through the piston or the valves bend ,destroying the valve guides causing a lot more damage and more $$$.Do you guys see what i am saying here.
Old 03-29-2005, 09:00 PM
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Hardened pushrods can still bend. I have done the 1-2-1 shift many times with nothing bad happening. I am not saying its good on the car but I couldn't see it being fatal, expecially with a LS6 (size) cam. Your fuel shut off will keep the car from over reving too much. (Just remember to use longer pushrods if you go with a SBC cam)
Old 03-29-2005, 09:24 PM
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Originally Posted by KCFormula
Hardened pushrods can still bend. I have done the 1-2-1 shift many times with nothing bad happening. I am not saying its good on the car but I couldn't see it being fatal, expecially with a LS6 (size) cam. Your fuel shut off will keep the car from over reving too much. (Just remember to use longer pushrods if you go with a SBC cam)
A misshift is a mechanical over rev,fuel shutoff can do jack about it.I should have saved a few bucks and put an SBC cam in my car,who knew?

BTW use hardened pushrods with a new cam/spring combo,don't forget a good shifter and don't miss a gear.
Old 03-29-2005, 09:27 PM
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The fuse theory.
You can read both sides to this one with a few good searches it's one of those things.......
Old 03-30-2005, 08:22 AM
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The problem really is that the pushrods already flex in the stock application. Aftermarket springs will only worsen the condition. Go hardened and hopefully your valves will stay in control. Even if they are, you now have to worry about a rod bolt letting loose at insane RPMs.
Old 03-30-2005, 08:54 AM
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Originally Posted by redtail2426
I dont think you guys understand what i am trying to say or ask.If i was to put hardend pushrods in while doing a small cam swap,ls6 cam for example,and then missed a shift and mechanically over-revved the engine.With the hardened pushrods being in there wont MORE damage take place.If i have the stock pushrods in and i over-rev the piston hits the valve forcing the pushrod or weakest and cheapest link to bend/break.With the hardened pushrods the piston hits the valve,the pushord does not bend but instead the valve goes through the piston or the valves bend ,destroying the valve guides causing a lot more damage and more $$$.Do you guys see what i am saying here.

Darkblue TA had this happen to him. He put the stockers back in for that exact reason. If you are running a slightly hotter cam, I'd say stick with the factory pushrods. If you over rev, miss a shift, downshift @ the redline instead of upshifting (yes it happens) you are correct, IMHO, to be repleasing bent pushrods rather than rebuilding a motor. Unless you have the need with stiffer springs, rockers, valves, pistons, just stick with factory. That's my $.02
Old 03-30-2005, 09:05 AM
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stock pushrods are not a fuse

here's an idea.... dont miss a shift!
Old 03-30-2005, 01:59 PM
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lets look at it this way. the stock pushrods are designed to withstand the stock cam and valvetrain loads. NOT aftermarket stuff. go ahead and run something out of spec if you want to, but thats your problem.

i can't emphasize enough how ****-poor of an idea it is to design an engine with breakpoints in it(weaker pushrods in case of a mis-shift). those components are not designed intentionally for that purpose, they won't always work quite like you think.

stock pushrods = good for stock application. they designed hardened ones for good reason, don't overlook that fact.
Old 03-30-2005, 02:56 PM
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wouldnt you want to bend a push rod before you destroyed valves?? Not that i want any part of my engine to be the weak point but......
Old 03-30-2005, 03:47 PM
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Well If i put in a ls6 cam i will use stock pushrods and anything bigger i will get the hardend.thanks guys
Old 03-30-2005, 03:52 PM
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Originally Posted by redtail2426
I know if you miss a shift or something with stock pushrods they will bend.But if you put in hardened rods and miss a shift,wont there be a lot more damage then just bent pushrods??
Well, they are more likely to break and cause them to shatter. You will then be looking for pieces in the crankcase.



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