Lots of cam/valvetrain questions, need advice.

[68stang351]

I've decided to put the roller cam I bought in my windsor. As in another thread, I was told that the specs are ok for my motor. The specs are 284/296 duration and .512/.513 lift. I'm also getting new roller lifters, and valve springs, and will also require new pushrods. Here are my questions.

1.) Does anyone know what length my new pushrods will need to be OR how to find out what length I need. I know they'll need to be shorter because of the roller lifters.

2.) Does anyone have any valvespring recommendations, or characteristics or specs I should look for in the new valvesprings? I was thinking about sticking with Comp Cams valve springs, as that's what the cam is and what the lifters
will be.

3.) I'm also considering putting roller rocker arms on too, but I am for sure going to do it later. Does anyone have a recommendation for the ratio. I was thinking 1.6.

The rest of my mods are in my sig, and yes they are stock 69 D0OE heads.

Advice would be greatly appreciated.

 

[slapper]

Once the cam is installed and the heads are on, use a roller lifter that has been made solid for tooling,(anybody you know have one? If not, you can make one easily), and get an adjustable pushrod(again, another tool), and mock it up on a cylinder. Set the length of the pushrod so that during the valve operation, the roller lifter(you'll have to have them for this, and yes, 1.6:1 is fine with your cam's lift),moves along as close to center on the valve stem tip as possible.
You don't want the roller on the rocker arm to be too close to the edge of either side of the valve stem tip for obvious reasons.
As far as springs, they should be matched to the cam. In this case, 550 lift springs should be good, as they will be less likely to float at higher RPMs. If you intend to race the engine regularly, perhaps somewhere about 580 lift springs would be better.
Just as a guess, I would say pushrods somewhere about 6.850" - 6.925", depending upon the length of the roller lifters used. Have your stock heads been outfitted with guide plates? You'll need them with roller rockers so the rollers don't roll off from the valve stem tips.

 

[slapper]

Oh yeah, follow the manufacturer's recommendations on cam install.
No moly on roller cams.

 

[66P51GT]

Here are a couple of articles:
http://www.compcams.com/Technical/Products/Pushrods/
http://www.trickflow.com/product/fordcylinderheads/rseries_sbford/pr_r_sbcford_pushrod.asp
http://www.grapeaperacing.com/GrapeApeRacing/tech/valvegeometry.cfm

Tool:
http://store.summitracing.com/product.asp?p=352&searchtype=ecat

 

[D.Hearne]

I wouldn't go too wild on valve spring pressures unless you install screw in studs too. Springs made for a .550-.580 lift cam will pop the press in studs out of the heads.