[Kenobi13]

So I got the Texas speed chromoly pushrods 7.850 - 3/8 Diameter. I was wondering if I can change them but I got the stock pistons and everything is stock for internal parts I was just going to add the blower and they said it's good to run with chromoly pushrods hold better on higher rpm but I see that people changer the pushrods when they do cams pistons and etc...
Any suggestions?

Thank you

[Norm Peterson]

Anything that increases the force on the pushrods is a suggestion (or requirement) for stiffer pushrods.

The issue is about how fast the lifter-pushrod-pushrod rocker socket group is being accelerated during the valve opening event, against however much resistance is coming from the valve spring rates/settings. Stiff valve springs, cams with quick valve opening rates, and higher revs (which obviously must be opening the valves faster) all increase pushrod load.

It's a stiffness thing, because under compressive loading, slender columns (pushrods fall into this structural category) will fail in buckling. But even before that happens catastrophically, they'll actually bend "out of straight" and potentially resonate at some frequency. Neither of which is good here.


Norm

[Kenobi13]

Originally Posted by Norm Peterson

Anything that increases the force on the pushrods is a suggestion (or requirement) for stiffer pushrods.

The issue is about how fast the lifter-pushrod-pushrod rocker socket group is being accelerated during the valve opening event, against however much resistance is coming from the valve spring rates/settings. Stiff valve springs, cams with quick valve opening rates, and higher revs (which obviously must be opening the valves faster) all increase pushrod load.

It's a stiffness thing, because under compressive loading, slender columns (pushrods fall into this structural category) will fail in buckling. But even before that happens catastrophically, they'll actually bend "out of straight" and potentially resonate at some frequency. Neither of which is good here.


Norm

Thank you so much

[Motor Fast]

That's a common modification for cammed cars. If Texas Speed recommends it then you should probably follow their direction. There are weak links in any system and it could be by design. By swapping out pushrods to ones that are much stronger just means something else may give before they do now. I've been running chromoly pushrods in my 2002 Camaro for 80,000 miles, nothing has yet to break.

[KingLT1]

LT stock push rods are already 3/8 diameter on these engines and fairly strong...quite a bit stronger then stock 5/16 pushrods in LS engines. It's a waste of money imo on a stock valve train engine. I have been running a supercharger for over 3yrs on a totally stock LT1 with no issues. Imo it would make more sense to move up to a slightly better valve spring if anything but again I haven't had any issues spinning 6700rpm @ 11psi of boost on stock parts.

[Joshinator99]

Originally Posted by Kenobi13

So I got the Texas speed chromoly pushrods 7.850 - 3/8 Diameter. I was wondering if I can change them but I got the stock pistons and everything is stock for internal parts I was just going to add the blower and they said it's good to run with chromoly pushrods hold better on higher rpm but I see that people changer the pushrods when they do cams pistons and etc...
Any suggestions?

Thank you

First time I’ve ever heard of pushrods being added to a blower package on a stock LT1…?!? If the rest of the valve train is stock, not sure why pushrods would be changed out. The lifters are a bigger problem IMO.

[s346k]

what was tsp's reason for changing pushrods? as stated already, they certainly are not the weak link in a stock internal engine.