hey guys, i got a 96 lt1 camaro not that it really matters but im in the process of cam swap and a general overhaul of the vehicle... anyways i took out the old cam today and put in the new one still far from done but i was looking over the old cam and it looked really clean except for one lobe that looks like it was rubbing hard and causeing where on the lobe, is this from lifter sticking or what just curious cause i don't wanna put it together and have it **** up my new cam

 

Can you post a picture of it? That would help a lot.

 

i'll get one sometime today when i find the time between work, but its just like scared at the top of the lobe i guess would be the best explanation....

EDIT: able to grab a pic during breakfast

 

Looks like bad wear and heat damage. I would not reuse anything that rolled on that lobe surface.

 

Is that a chip?

 

My hotcam had some chips like that when I pulled my engine apart to rebuild it about 4 years ago. It was the first time I ever put a cam in anything and I thought it was just from inexperience. I do see cam lobes like that at work on some of our g vans but the engines have about 500,000 miles on them usually when they get replaced. I'm sure some of these guys know what exactly causes this, I'd like to know also.

 

A chip like that I would think could be caused by valve float, the lifter gets tossed over the nose and maybe chips the lobe on landing.

 

Looks like it.

 

That looks like it was hammered for a while by a loose lifter for one reason or another. Did you have anything unusual about that rocker arm/rocker stud/pushrod/valve in that position? Maybe the lifter has a clue too - if it collapsed or whatever happened to it. I bet some other part is screwed up. The roller pattern on that lobe looks wide compared to the other ones as well.

 

i took rockers off pushrods off everything looked normally i still haven't looked at the lifters they've been sitting in a bag in the shed, i might take a look after dinner, was just curious because i was hoping to not have to buy new lifters even though i should but my opti seems to have seen better days and now i got to worry about replacing that first...... my head cam project is becoming so much bigger then expected haha

 

The roller lifter is VERY hard.
There are cases where cams and springs are very carefully chosen to allow the cam to throw the lifter over the nose of the cam and catch it for extra lift at high rpm. That would not be the case with stock parts and we know stock springs are weak. Though I though float induced cam damage was usually a little further down the backside of the lobe rather than so close to the tip.

When valve float hurts power is when the valve bounces off the seat allowing compression to escape.