Difference Between Valve Jobs & Backcut Valves

[yarcli52]

I'm not real familiar with the valvetrain yet and I was just wondering what the difference is between 3 or 5 angle valve jobs and backcutting the valves.

[mopar2ya]

Typically the more angles the tighter the air will hug the valve, increasing flow. We use radius cut whenever possible as we feel it gives the best flow.

Back cutting is where they remove a little material from the top outside edge of the valve and come back towards the stem some.

[yarcli52]

So valve jobs are done on the bottom side of the valve?

[mopar2ya]

Where the valve and the seat in the head meet. heres a decent link...Valve Job - Tech Articles - Stock Car Racing Magazine