I just started re-assembling my engine after a head swap & noticed that one pushrod was bent. I looked at the heads & pistons as I took it apart, there was absolutely no sign of contact from the valves & when I took the engine apart it was running fine with no rocker arm clatter.
My springs(old heads) were good to almost .100 more valve lift that I was running so it shouldn't have been from that. Because there was no noise, I'm assuming it's been bent for a while & I took up the slack on a previous valve lash(solid cam).

These were a fairly cheap set of Crane hardened pushrods, could I have just got one weak one & it bent just from normal use(ie abuse)?

I've never seen a pushrod bend without a good reason, could this be a first for me?

It is possible that it had a very slight tweak in it from the beginning and over time it continued to bend, with you compensating by adjusting the lash. Pushrods are one area that shouldn't be skimped on in a race engine, regardless of the style of cam. Check into the Comp Hi Tech's, they'll handle whatever you throw at it. ;)

Stop. Check the intake bolts. In a couple places a bolt that is just a bit too long will hit the push rod. Only other thing might be coil bind of the valve springs or spring retainer hitting the guide, be a high lift cam but it can happen.

Tom, there are no scratches or rub marks on the bent rod, I looked it over very carefully trying to see a flaw.

Doug, a slow & gradual bending is most likely, these have been in the engine since I swapped bottom ends in Sept/05 & there hasn't been a single point where I have noticed a large change in valve lash.

I do adjust them every 3-4 weeks during the racing season so a slightly increasing bend makes sense.

Damn, I guess that's where my missing .05 of a secong was last year, a cheap pushrod probably cost me my 10 second run!!

The Hi-Tech's are ordered & will be here tomorrow!

Not to worry Greg, the 10's for you can't be but a month or two away. ;)

With my AFR 195 heads, bigger headers & Pro Systems carb, I'm hoping for a 10 second run by the end of May.

I'm going to tune it for a high 11 NA & then hit the juice after the track get some rubber laid down.

Gregh, you ended up getting a carb from Pro systems huh. What did he build for you?



Jerry

It wet flowed 901 cfm, here are all the specs.
http://www.casemp.com/gregh/car/carb1a.JPG

http://www.casemp.com/gregh/car/carb2a.JPG

Have you had it out yet??
What does the seat of the pants dyno say about the changes?

I've put about 50-60 miles on it so far, haven't really had a chance to beat on it too hard & it still needs some tweaking but the car feels like it did last year WITH the 100 shot of laughing gas.

I'm guessing between the bigger headers, heads & carb, I'm up 70+ hp.

That should be enough to get me with in my goal of high 11's on motor & mid to high 10's on a 150 shot.

I've put about 50-60 miles on it so far, haven't really had a chance to beat on it too hard & it still needs some tweaking but the car feels like it did last year WITH the 100 shot of laughing gas.

I'm guessing between the bigger headers, heads & carb, I'm up 70+ hp.

That should be enough to get me with in my goal of high 11's on motor & mid to high 10's on a 150 shot.

Excellent :cool:
Hopefully I can get out within a week or 2. Spur of the moment thing, sold all my wheels & tires to a friend. Car is up on jackstands shoeless
I need my head read :screwup:

Jerry

I still have my old set of wheels & tires, the American Racing Wheels, Outlaw II's kicking around if you need a temporary setup.