88TPI406GTA

I have a set of Pro Action aluminum 220cc heads that I am assembling the valve train on...I realize that after tightening the valve lash that the pushrods are actually in contact with the head.

Now I have self-aligning rockers and no guideplates so I know that the pushrods can move a bit...but one direction of travel has it in contact with the head...

What do I do?

I figure options are these...

1. Finish assembling engine...start it and let the pushrods do what they need to do...I have hardened pushrods and aluminum heads...they will make their own groove?

2. Take the heads off and grind the pushrod slots bigger...but then I have to buy new head gaskets and head bolts (extra $100) and wait 3 days for parts to show up...

How much play do SA rockers have?

Any input would be appreciated...TIA

RB83L69

Self-aligning rockers, or narrow-slot heads; one or the other, not both.

Get the right rockers for your heads.

88TPI406GTA

The bizarre thing is that these heads are not supposed to be narrow slot heads...You are supposed to be able to use either...

I thought that only OEM designs were narrow slot...

And they come able to use either center or perimeter bolt valve covers...I suppose there is no correlation there...

RB83L69

So are the slots narrow, or not??? Screw "supposed to be", move directly to "are they".

88TPI406GTA

After checking the Pro-Topline site...I realize that I have some differences according to what they recommend for valve train stuff with my flat tappet cam

1. I have 3/8" rocker studs and they recommend 7/16"

2. They recommend a Scorpion roller rocker which is a non-SA type.

Competition Products told me that my setup would be OK...

I suppose Pro Action recommends the standard roller rocker type because of the narrow pushrod slot?

88TPI406GTA

The pushrods are in contact with the head...the answer would be, yes, narrow pushrod slot because of the contact...

I went back outside and checked and sure enough, they ALL are in contact with the head...

RB83L69

Well I guess that answers that. If the heads have narrow slots, lose the self-aligning rockers. Pretty simple really.

88TPI406GTA

Pictures help...

88TPI406GTA

#2

88TPI406GTA

here is a stock 400 head

88TPI406GTA

The stock head is obviously narrow...but is the Pro-Action head considered "narrow slot"?

RB83L69

Indeed, pictures help.

Those are not narrow slots. A die grinder would be the course of action. Looks like the combo of the high ratio and SA rockers has moved the push rods to a place they can't quite go without a little more clearance.

Rocker stud diameter is irrelevant BTW.

88TPI406GTA

Sweet...RB83L69, I appreciate your help...

As I looked at the small distance between the pushrod slot and the intake port...I don't know how I feel about grinding there...

I think I will just order standard roller rockers and guideplates since the heads are already on the engine...and since Pro-Action recommends standard ones...but I have to talk to Competition Products on Monday...so I have tomorrow to think about it...

RB83L69

There's a good chance that any 1.6 rockers, rollers or using guide plates or otherwise, would put you right back where you are now.

If it was me, I'd pop the heads off and relieve the holes, after marking where the interference is; and if your final theoretical valve lift is lower than within about .050" of the valve springs' "specs", I'd go ahead and run those 1418 rockers.

Rule #1 of "bolt-in" parts":

"Bolt-in" parts.... don't always quite "bolt in". A little massaging here and there may be required.

F-BIRD'88

You do not need to replace the head bolts just cause you removed them. Small block chevy head bolts are not "torque to yield" bolts. Just clean them and reinstall 'em.

If the motor has not been fired since installing the heads and head gaskets, you can remove the heads and reuse the gasket too.

88TPI406GTA

I have ARP head bolts and Fel Pro head gaskets...I thought that ARP IS torque to yield...also, since you compress the head gasket when you torque it down, I thought that you also wanted to replace it to make sure it seals...

RB83L69:

"if your final theoretical valve lift is lower than within about .050" of the valve springs' "specs", I'd go ahead and run those 1418 rockers. "

Well, my valve lift with 1.5 rockers is .464...the valve springs can handle .550 lift...so that is why I feel safe to use 1.6 rockers...but not if they are going to contribute significantly to the clearance problem.

88TPI406GTA

Also, I know for a fact that Fel-pro stock replacement sbc head bolts are torque to yield as I used them a few years ago...and the warning is very clear about it.

F-BIRD'88

You're going to think yourself right into the poor house.
The head bolts will be fine to use over again.
The head gasket will be fine too. Same heads, same motor,
never fired. I'd use 'em over again.

But..... its your money.....

88TPI406GTA

You are wrong...this car has ALREADY put me into the poor house...

I just don't want any head gasket issues because I was lazy or trying to cut corners...

StangKiller

By the looks of those pics you only need to remove a tiny amount of aluminum, I think I would cover the lifter valley real well, go buy a round file about 3/8 dia. load it with grease and use it to file the heads right where the rod hits, the grease will hold most of the chips and the covering should catch the rest, wipe off and regrease the file after every cut. I did that to a pair of Mopar heads once and it worked very well.

jimmy_mac

I helped my brother put his Iron Eagle headed motor together recently and his valve train lined up very similiar to what you have there. But his head came with guide plates. I was a little worried about it myself seeing as how there was so much room on the other side of the pushrod. But we have checked the valve train a few times since the motor has been running and there is no wear.

B4Ctom1

When I put my pro-action aluminums on, I moved the guideplate around until I barely had clearance. I didnt have SA rockers, there was a slight sacrifice to geometry whereas the roller is wider than the valve stem tip, the roller is over to one side on the valve. I would consider it bad if the edge of the roller was running over the top of the valvestem tip. Mine isn't doing that, but the roller is not centered over the valve stem either. The amount of clearance I gained was so small that I needed a flashlight to see it. A better solution in hindsight will be that if I ever remove the head for anything I will have these opened up some.

88TPI406GTA

OK...here is what I have found...I bought a stock old style rocker arm (1.5) and a SA stock rocker arm and mocked them up...no difference in clearance...this means that the rocker arm type that I have, along with the ratio difference is moot.

After checking with ARP, their head bolts are NOT torque to yield, meaning I will be reusing them...and I decided to buy a new set of head gaskets...because worst case scenario, I don't want to replace them in the car...

Lastly, when I checked the pushrods again, I realized that the clearance issue is only on the intake side...not the exhaust. I called Competition Products, where I bought the heads, and they said that on larger intake port heads, no matter what the manufacturer, this can be an issue...

So I will pull the heads off in the next day or so and clearance them, then reassemble...

I will post an update on clearance after i get done grinding...

88TPI406GTA

Took longer than I thought to get the heads off

How much pushrod clearance do I need with SA rockers? Right now I have between 1/16 and 1/8 of an inch...and of course I can see light all around the pushrod...

RB83L69

I'd shoot for .100" or so.

88TPI406GTA

Excellent...thanks again for your sage guidance...

This whole experience almost makes me wish I HAD bought the damn AFR 195 heads...but I am sure in the long run, I have made the right call...one set of heads for a long time to come...