I have a set of Sportsman II 11250-1 heads that will be going on my 87 350. I plan to run 1.6 rockers and the info I see says to elongate the pushrod holes.
I haven't seen a dimension on how much opening they will need. If someone could give me an idea of how far to open them up that would be good before I put them on and find out it's not enough or i spent all day grinding.
Also I'm using the recommended Felpro 1003 gaskets on them.
Does 0.040 seem thick to you?
TIA

 

You barely have to touch the bottom of the guideslot. Pull all the plugs on the engine so you can turn it over easily. Now place 1 rocker/pushrod assembly on and slowly rotate the engine over by hand. If the intake is off put a flashlight in the galley so you can see, if not then you can use some masking tape around the pushrod to determine the amount. That will give you some idea of how much, and depending on the head basket/deck height/etc the amount will be slightly different.
I did another post on this awhile back try search and see what happens.

Found it...
That's fine, sometimes they will fit, but you should still check them. It will show up this way. If they barely hit, then at idle there will be lifter noise like a mis-adjustment, but from different lifters, not just one, or it will be intermittant. Really, it will drive you nuts trying to figure out what's goin' on.
The deal is that the pushrods are just barely hitting enough to cause the lifter to bleed down (forcibly) and cause the rattle. When you crack the throttle the extra (oil) pressure forces the lifter to pump up and the noise will go away. The area they hit is the top of the guideslot. If not corrected one of three things will happen. 1: The pushrod will wear down a few thousandths and the noise will go away, and all will be good. 2: The pushrod will wear away and then when you rev it up it will break and wreak total havoc. or 3: They will bend and the noise will go away and when you rev it they will break and wreak total havoc.
The way I fixed mine, and this is somewhat crude, is that I taped off everything that I could, stuck rags in everything else and using a pushrod as a guide, used a die grinder to "massage" the top of the guideslot. It doesn't take much. Then I cleaned everythign up with a shop vac.
It all depends on gaskets, deck heights, slot , really a bunch of variables. Some will be fine, some won't.

 

Thanks, I saw that thread about 10 mins ago
I think I'll just go ahead and clean them out a little to be on the safe side. That way I've got a better shot when I put the heads on. right now their still off so it will be easy.
Jp

 

Check first, the slots may already be opened up if they're aftermarket.

 

The note from the World website says they "may" have to be opened up.
I'll just do a light touch on them.