I did. I'm not 100% sure how, and it wasn't bent bad, but it was making my car act about 300 kinds of funny. I replaced my Comp Cams rods with some Trick Flow single piece ones. They are oh so nice and the car runs like it is supposed to now.

I got my miracle friend to adjust the valves for me, he found the bent rod. We replaced them and readjusted the rockers and it runs like a dream. It just feels so good to drive it again. I'd been driving my dad's F-150 all week. :U

 

DAMN

 

Kinda what I said. My next thought was "where am I going to get a set of hardened pushrods at 6:30 on a Wednesday" Luckily a friend of mine had a set, his motor is apart, and he's going to go solid roller anyway and had no use for these. They are certainly some nice looking rods.

 

Nathan: were they the same length rod as the bent ones. were they lt1 or did you upgrade with the hot cam to lt1. I don't know if I need the same length as the stock rods for the LT1 I am redoing with the hot cam and 1.6 Crane Gold rollers and 125# z28 springs. Any easy way to check the required rod length to know which to order. Do you just put a dial indicator on the rod, look at max/min positions, measure any gap between the roller and rod, and order accordingly...sounds too easy so what logical error am I making. Thanks for any guidence in this area with the installation of the Hot Cam in an otherwise stock LT1.

 

My rods are still stock length. The only time you should need to change that would be if you had maybe some longer valves, taller springs, taller heads, or different lifters or something.

Roller rockers, and all of that typically doesn't affect it. I've never actually measured one, I knew it was the right rod. I just kinda stood it up beside the old rod to make sure it wasn't blatently different.

 

I managed to bend 3 once a long time ago when I overlashed the rockers on a hydraulic roller setup that the lifters had pumped down on. Turned it over and whammo, 3 bent rods.

 

Yes and I've broke them into multiple pieces too :smash: When I was 16 yrs old I bought a set a camel hump fullie heads for my 350 Malibu, Turns out after installing them one day, they were shaved way too much and my valves were hitting the pistons...Actually it was kind of weird starting the motor up without the valve covers on a and watching the pushrods dissappering one by one and wondering why :D


[Modified by JB'S LT4, 8:36 PM 6/20/2002]

 

What is the stock lenght anyway? Is it 7.200" for L98 engine?

Thanks,

 

Hey Nathan,
Wanted to say good find and glad to hear she runs A-1 now.Bet its a world of difference.

Btw,is the GM pushrods in that engine uses a pressed on tip?I dont know the LT1 specs too well,but wondered what GM uses for that.
:)

 

Push rods don't "just bend". When one or more do bend, it's usually due to interference and binding of the pushrod against the cylinder head or valve spring coil bind or excessive spring pressure for the strength of the pushrod (like when running springs that have 700#+ open spring pressure with 5/16th, thin wall pushrods.

Many times, when you make mods to an engine, especially in the valvetrain, (decking the block or cutting the heads or making a substantial change in head gasket thickness) a different length pushrod is needed.

There are several methods of determining the correct pushrod length and the best way is to buy a tool specifically for that purpose along with an adjustable pushrod. There are the really inexpensive blue ones, which I think are made by Moroso, or the more eloborate ones made by the big cam companies like Crane and CompCams.

You can try eye-balling the rocker tip as you hand cycle the engine through a couple of revolutions, but this is pretty hard to do with the engine in the car. With a mirror and a lot of patience it can be done though.

To roller tip or the rocker arm should sit toward the intake manifold side of the valve stem tip when the lifter is on the base circle of the camshaft lobe,

Then as the engine is rotated, the roller tip should move to the center of the valve stem tip when the valve is at mid lift and as the valve is moved to full lift, the roller tip should move across the center line of the valve stem tip toward the outboard side of the valve stem tip.

Inboard, center, outboard, center, inboard is the movement you're looking for with a roller tip rocker.

I know that the iron L98 heads were notorious for bending pushrods when a high lift cam or high ratio rocker are used.

If one pushrod is found bent, then all the others become suspect too. I'd definitely replace them all, but I'd first find the cause.

Hope this helps.

Jake

 

You bring up some very good points Jake. In the case of mine I know it was bent because I had the rockers adjusted too tight. The Hot Cam, 1.6 RR setup is very common and proven to work well with stock rods. Thus it was something I did. But yes certainly do your research. And yes again one or two of mine were bent, they were all replaced.


[Modified by Nathan Plemons, 3:37 PM 6/20/2002]

 

I bent one TWICE on the '85 :( :( The second time I was going around a corner going into second gear when I heard it go :eek: After the second time we did more than just replace the rods, we did the whole valve spring kit and so far, so good *knocks on wood*