Deep scratch- GM 454/438hp roller cam

[Machtuck]

Ok. Good information. I’ll look into this.

[Machtuck]

Well, i inspected the cam and found no taper whatsoever. I did however, find another deep scratch on the third lobe. So the first and third lobes from the front of the cam are scratched. I matched one of the roller lifters to the cam and found that those lobes would have driven the same set of hyd roller lifters. This leads me to believe that i installed the cross bar incorrectly and like Mike and others said, this caused the wheels to ride on the edges. If this did occur, I’m darn lucky that I didn’t destroy the lifter set. There are no arrows on these lifters for guidance. I didn’t know that they could be installed incorrectly. Do you all think that this is what happened? Thanks for all of your help.

[ProPower engines]

Putting in a pair of lifters backwards would be real noticeable and I would bet you would have seen that long before the intake went on. And some blocks while they will allow the pair to install the wrong way when the engine is running the tie bars take a beating and fail shortly after that from the tie bar locator pins rubbing on the blocks valley area wall.

That said you should use a magnifying glass and check the tie bars and the locating pins for wear/twist.
Have the cam re-profiled and carry on.

[Machtuck]

Yeah, i just tried to install like this and there is no way that i would had done this. I’ll take it to a cam grinder and see if it’s worth regrinding. Thank again

[MadBill]

Is this the only roller cam that's been in this block? There's a remote possibility that two lifter bores are badly misaligned in the fore/aft direction, leading to edge-only roller contact. (Or, I suppose, that the roller axles are not at 90° to the bodies...)

[Machtuck]

Yes, this was the only roller cam that has been in this 402 block. It must be a misalignment issue. Gonna mock it up tomorrow.

[econo racer]

I have never understood why lifters are not running on the dead center of the camshaft? Hope you get another cam, maybe even make more HP.