Competition Stock tappets with billet cam

[dzlpwr]

Is there anyone out there running stock tappets with a billet cam? Just curious as Enterprise Engine claims that they haven't had any problems doing it so far. I would appreciate any good input.

 

[Redram 1]

re.

I know of alot of guys running them. Never heard of any problems.

 

[DRadzierez]

Stock tappets can break above about 5500 rpm.

 

[sbentz]

Stock tappets can break above about 5500 rpm.

And a few other things.

 

[COMP461]

The reason most valve train parts break is Uncontrolled Valve train Motion, plain and simple. This is brought about by lack of valve spring pressure for the most part. The more you develop cam profiles, making opening ramps more aggressive and extreme RPM you push these ancient tractor motors too, the more these problems rear up, unless you address the issue of keeping the parts in constant contact with each other.



To answer you question the stock lifters are ok, but use the later 24 valve because of the advantage of a larger diameter mushroom face. If you going to run a billet cam you must address the incompatibility of the steel cam to the iron block, and either installs roller bearings, not advised on the street, or stock hydro dynamic bearings.



Valve spring pressure can be fixed by installing some of the springs Ray Little at RAYMAC Racing Engines puts on his motors and along with these comes a good quality Titanium retainer that give you the ability to run . 150 more lift on the cam . These springs drop in the same location as a stock spring and set up at 140 lbs on the seat

These same springs were on the latest high hp VP44 dyno champ that made well in to the 800 range Rays number is 817 477 0682

 

[dzlpwr]

Hey guys thanks for the great input. Im already in the process of installing the cam bushings in the block as that was a no brainer. I was just curious about the use of stock tappets.