cam
 

I am looking at a cam. I was wondering if a 523/513 cam would work with a stock set of 351W heads. Also would I have to check piston to valve clearance.

Re: cam
 

The duration has a lot to do with your piston to valve clearance. What year are the 351 heads you have? No matter the year, you will need to upgrade the valve springs. I would imagine you would be alright with ptv clearance, but you ALWAYS need to check it. What motor is this going in and what are the rest of the cam specs?

Re: cam
 

The duration is advertised at 280/285 duration at .050 is 230/235. The motor is a 78 351W and It is going in my 87 mustang. The Rpm range is 2100-6900.

Re: cam
 

Don't hold me to this, but you should be ok on ptv clearance. As long as you use the stock heads with stock valves. I assume you are wanting to do this. You will have to upgrade the springs though.

I should add that, that is too much cam for a stock engine and stock heads.

Re: cam
 

The heads are ported and was looking into different springs. This is going to be a 393 or a 408 stroker. Thanks for the input.

Re: cam
 

Just saw some springs but it says that the heads will need machine work in order to put them in. what machine work will need to be done. It is a double spring setup. Also what size rr should I use.