chrysler kid

iTrader: (14)

I'm just glad I was young and smart stupid and took a good tuners advice and had hardened chromoly pushrods from two installed when I had a shop put in my cam and springs.

Futral cams never had the strongest reputation but my magnetic drain plug has been shaving free for ten years with the exception of needle bearings a few months ago

It also makes me wonder if some of the issues I had with comp valve springs in my older builds really had to do more with stock pushrods and scrubbing on the valves

NA99T/A

the push rods were texas speed hardened chromoly 7.400 5/16 diameter.
So you would suggest a 3/8 diameter chromoly pushrod would be better?
what are the disadvantages to a larger diameter pushrod and will they simply drop in place or is machine work required to run them?

tech@WS6store

iTrader: (2)

Everyone seems to be jumping the gun and recommending overkill for no reason.

Your build is just like a thousand others. It was likely the lifter that either failed and stuck in bore or stuck in the bore and failed. You affirmed that when you said a few had to be pushed out not pulled out. Ive seen orig lifters mushroom quite a bit and im not going to proclaim i know why.

The best thing to do is check everything, have the block cleaned and then assemble back however you want within your budget and have fun. there is no need for bigger pushrods or expensive lifters or any of that. after its back together get a good quality break in oil, change it when recommended and that's it.
Put it back together with quality parts and have fun.

txazformula

iTrader: (8)

I hear what you're saying about not over complicating the situation, but the thing about it is most everybody on this forum has a build like a thousand others, and it seems like you could have a lot more fun driving your car after you put it back together if you understood what screwed it up the first time.

tech@WS6store

iTrader: (2)

Autopsy reall points to lifter. Esp if that cam lobe was not scarred as bad. also lifter explains the valve hitting piston

vettenuts

iTrader: (4)

Straight 3/8" won't typically drop in. 11/32" usually do drop in. I went with 3/8" double taper and they fit in my AFR heads but I rolled the dice when I bought them that they would fit.

11/32" 0.120" wall thickness is 60% stiffer than 5/16" 0.080" wall. That is a considerable increase.

Disadvantages: None.

CNC-Dude

You mentioned at the beginning that the cam was already installed by the previous owner when you got it, so a lot of unknowns about the condition of the parts that were used. The lifters could have been like the remaining ones you have with the roller wheels being rough as you mentioned when the cam was installed, and the one that failed was just the first one that did. Once the wheel quits rolling, it skids around the lobe and the damage grows from there eventually to sticking in the bore. Since that cylinder was the only one with valve contact you mentioned, it is fair to assume as was pointed out, that this caused the P/V contact. So going overkill is truly on your dime, and may not be necessary. You may want to also thoroughly check all the valvetrain components and make sure this cam swap wasn't a shadetree job with other hidden problems waiting to creep up.

vettenuts

iTrader: (4)

Trying to figure out where the overkill is?

chrysler kid

iTrader: (14)

Your lifter failed.

You haven't posted any pictures of the valve train or verified if you have a bent push rod.

Pull it apart and post some pictures of the valve train in the head and also show us how bad the cam is scarred.

tech@WS6store

iTrader: (2)

Spending possibly $100 more just for pushrods seems overkill esp on such a vanilla build. Its literally been done the same way prob tens of thousands of times. With shorter and longer prs is prob a good guess and they all turned out fine.
There is no reason to choose the 11/32 prs over the 5/16 std that everyone carries.

NA99T/A

I dont get to work on the car but about once a week as its not in my garage, but got to look further into it the other day and took a few pics. found a broken spring on cylinder number 3 which was where the piston that hit the valve was of course. the lifter that failed was on cylinder number 6. but as you can see in the pics of the cam, most lobes were damaged as most the lifters had damaged rollers.

tech@WS6store

iTrader: (2)

At this point it is a VERY good idea to yank the block and at least pull the oil plugs, barbell, and oil pan. Check bearings, and oil passages. It may cost extra, but all that material has to go somewhere. Most may stay in oil pan, but ive seen it get caught in the oil barbell and on the oil galley plugs etc.
Check cam bearings too of course.

Looks like abuse and lack of maintenance caused it.

NA99T/A

yeah motor has already been pulled, will be doing complete rebuild. I bought the car with the cam in it, drove it about 1500 miles and here I am. Im just trying to figure out the cause to prevent this from happening to my new build. when you say lack of maintenance what exactly do you mean?

G Atsma

NOT changing oil/filters.

NA99T/A

changing oil/filters is kind of common sense stuff or one would think so anyways, I thought he might of meant some other kind of more involved maintence that is needed when running a larger aftermarket cam/springs.

handyandy496

iTrader: (9)

Its more than likely valve float that caused the lifter to fail or it failed on its own. Hardened parts can easily fail if cracks occur and are not caught by the manufacturer. Valve float will put so much strain on the parts this might have happened anyway. I had a vette sb That would rev to 8000 (miss shifting) but when ever I did I would check the pushrods by rolling them on a flat surface.
I remember replacing quite a few pushrods before getting the right springs.