Im building a motor right now and was at the point to decide to go with a hydrallic roller or hydrallic flat tappet how much more power do you gain by using the roller? Is it really worth the extra money going with a roller cam ? And how do you find out if ur motor was a OE roller motor?

 

Yes its most definitely better to have a roller cam. The oil companies have started taking zinc out of their oils to reduce emissions, and flat tappet cams need zinc additives to keep from flattening a camshaft lobe. The roller lifters will run just fine on today's oil. So if you have a flat tappet cam, you need to get either special diesel truck oil, or regular oil plus a zinc additive.

Also, roller camshafts have better profiles, with quicker ramps to get the valve open sooner, and let it stay open longer. Not to mention its better to have a wheel than scrape across on a flat surface. Roller cams usually get slightly better gas mileage and better emissions, too.

A roller block engine will have a one-piece rear main seal, and it will have the three "posts" in the lifter valley for the roller lifter hold down (usually called a spider). The flat-tappet block will not have the three posts.

Roller camshaft blocks started in GM passenger cars in 1987. Some trucks have roller blocks, but flat tappet cams. You can use a roller cam in a truck block if it has the three posts. Or you can use a flat tappet block with aftermarket roller lifters, but those are usually more expensive.