hey what are you guys opinion on this engine?

http://allchevyengines.com/454-425.htm

ill definately throw in a big cam when i get it. would it require any extra steps to convert from a flat tappet to a roller or is it just bolt on?

Originally posted by slpin:
would it require any extra steps to convert from a flat tappet to a roller or is it just bolt on? While by no means an expert, I have run big mechanical rollers in my last 2 big blocks, A few things to check:
1. Piston to valve clearance, mock up with clay, set lash, look for .100-.125 clearance on the exhaust valve.
2. The heads also have to come apart, besides changing springs, measure distance between retainer and valve guide, probably have to have the guides cut down.
3. Also need to retain a roller, ie: thrust button and torrington bearing behind cam gear. I prefer an aluminum cover cause it doesn't flex.
4. Some rollers require a bronze distributor gear.
5. If you are talking about an agressive mechanical roller cam, get quality 10 degree retainers and locks, severe duty valves, and a stud girdle.

Originally posted by thor27:
</font><blockquote>quote:</font><hr />Originally posted by slpin:
would it require any extra steps to convert from a flat tappet to a roller or is it just bolt on? While by no means an expert, I have run big mechanical rollers in my last 2 big blocks, A few things to check:
1. Piston to valve clearance, mock up with clay, set lash, look for .100-.125 clearance on the exhaust valve. ok
2. The heads also have to come apart, besides changing springs, measure distance between retainer and valve guide, probably have to have the guides cut down. ok
3. Also need to retain a roller, ie: thrust button and torrington bearing behind cam gear. I prefer an aluminum cover cause it doesn't flex. i dont quiet understand with the button and bearing and stuff. so before i slide in the roller, what do i need to put in?
4. Some rollers require a bronze distributor gear. ok
5. If you are talking about an agressive mechanical roller cam, get quality 10 degree retainers and locks, severe duty valves, and a stud girdle. ok </font>[/QUOTE]thanks