I have aluminum heads with a Lingenfelter 74211 cam and scorpion 1.6 narrow body rollers. They were hitting the stock height covers, actually the cover wouldn't even sit down on the head. I picked up a set of the GM Proform cast aluminum center bolt covers that are 1/4“ taller. However these have a lot of float. There's no real center bolt guide tube. On first start after this build I heard a rocker smacking the cover over the number 1 cylinder. I unbolted it, heard a pop and it seemed to reseat itself. So I torqued it down. The issue now is both covers are leaking in the same spot. Between 6 and 8 and 5 and 7. I have the Felpro blue silicone Gaskets. Am I missing something here? This shouldn't be so difficult. I've never used a cover that moves back and forth and up and down like this one does. My heads except both perimeter and center bolt. I doubt that's the issue.

 

I have the same covers on my fastburn heads w 1.6 gm aluminum roller rockers. I agree, the covers don't really center well. I'm using the same gaskets as you also. If I'm not careful w the cover placement they hit the roller rockers. I adjusted them w the engine idling and got it right. I would imagine if you get them just right they won't leak or make contact. I haven't had any leaking issues w mine. I don't even tighten them a lot because they're fairly thin cast aluminum and I'm worried about them cracking. I'm happy w them but they're definitely not perfect.

 

It's a bit ridiculous to spend that kind of money on performance gear only to have to fiddle fart around to adjust the most basic of things. A valve cover for a small block Chev should be a cut and paste operation.

 

Yeah, I totally agree. It's frustrating and they're not cheap. My heads are both center and perimeter bolt pattern so that shouldn't be your issue. I'd keep messing w them, I've had mine on and off a few times and other that messing around to get them centered they've been good.

 

Aluminum rocker arms have rather thick body over the top of the roller tip. for strength.
The +.100" valves also move that rocker higher up.
No mystery the rockers are too close to the rocker covers. Get tall covers or double up on the gaskets or get the rocker cover gasket adapter spacers.
Those are good strong rockers. I'd fix the covers to make clearance.
How is the manufacturer supposted to know what none oem stock parts you are going to combine?
Ya you cannot crank down on the cover bolts if when there is no internal bracing in the covers.
If the cover flange is not true flat, straight its not going to seal up.
The stock oem rocker cover height is made to clear stock style rockers with stock length sbc valves.

I like the thick fomed rubber orange rocker cover gaskets. $$$ but reusable.
Racers have been stacking rocker cover gaskets for 50 years for more clearance.
Again if the mounting mating flange on the covers is not flat its not going to seal up.

So. is the rocker cover hitting the body of the rocker arm or hitting the rocker stud/ poly lock?

 

Mine actually hit on the sides
of the front most and the rear most rockers. They just needed to be centered carefully.

 

I stuck a boroscope camera inside the oil hole and there looks to be plenty of clearance. As I mentioned. I got these because they're 1/4 inch taller. The stock ones sat on the tips of the rockers. These do not. The oil started leaking as I was pouring it. It's not sitting on the rocker. There's quite a lot of play with these covers. The stock ones sat down and that was it. These damn things float front to back and side to side. They are not sitting on the rockers like the stock cover did and there's tonnes of room over top the Poly locks. The stockers had bolt tubes that went right down to the thread boss. These covers do not have the tubes.

 

My remedy for the leaking Proform covers was to RTV the blue silicone to the rocker cover.
The register never was problematic for me but one thing I DID notice was that the bolts supplied with the covers bottomed out in the head before the cover was snug. I even managed to break one of them off in my first go around. This is the centre bolt application but I also have perimeter style installation if I wanted.

 

I believe I found the problem. Absolute Gong show. The valve cover seal flanges are to thick for the aluminum head because the sealing portion of the heads are also thicker than the cast iron heads. Add those to up and there's interference with each other. So I removed the valve cover and Dremel'd out the end towards the front of the car. Basically took the flange out to where it begins to radius towards the exhaust and intake manifold sides. Left enough to hold the gasket. It appears to have dropped down now. I can no longer see the blue gasket. Unfortunately I now have to do the same with the passenger side which means taking a lot apart. Including the plenum so I can loosen the Edelbrock runners in order to lift the valve cover. All that for a bloody valve cover. Hence the Gong Show.

 

Good call on the hold down bolts length check.
And finding the valve cover flange interference.
Nixay on the Blue RTV.. Stack up 2 gaskets.

 

I like that you found the problem.

 

These are my fav center bolt gaskets cork, steel core so they hold shape and 1/4" Thick! Felpro 1648 https://www.summitracing.com/parts/f...xoCqoEQAvD_BwE

I never have glued a gasket to the cover, only time I couldn't get valve covers to not stop leaking was a ring blow-by issue and thicker oil fixed that.

Are these the Proform cover type? http://www.spiderautomotive.com/gm141130.html

Also ANY cast cover needs the rails cleaned up, due to sharp casting dots/lines/marks or they will cut rubber type gaskets. Learned that the hard way.

 

Pro Form 141-131. According to Summit they do clear the rollers. And these ones do as I looked under the cover with a boroscope.

 

My point was thicker may have not hit the head or how ever yours hit(w/o pic I'm not sure exactly how they hit) that you had to grind it down and also they won't squish as much as rubber.

Still even then diff brand rockers have thicker bodies or diff pushrod cup location, longer rocker poly locks & studs(There are more than 20 or so lengths), longer valves or lash caps, diff heads have higher VC rails n so on.... always several factors. There are limitless combos for SBC since it has had a HUGE variety of aftermarket support for a long time, tho it is dwindling now somewhat.

 

Actually just scored a cheap set on ebay Glad I remembered because of this thread. Got a great deal on a new set of Holley cast center bolt valve covers for one of my future projects, so now I'm GTG! Prices are gong up on a lot of stuff and some places have them for $65!!!

 

This was an exercise in patience and not throwing tools. Good lord those were brutal to setup. Put it all back together and fired it up and the engine sounded like a misfire. Finally got it to somewhat idle enough to get out to the front where again heard and felt a smaking on the driver's side cover. I think the knock sensor must have picked it up and seriously retarded the timing. Turns out the #1 intake rocker was pranging the damn oil damper. When I loosened the cover I heard a pop as it released. Dinged the side of the rocker a bit as well. Theses are narrow body. Perhaps it was a design issue on the cover. Either way I crushed it a bit with pliers and started it again. Seems ok now. Now I can finally start tuning the damn thing. Spent 2 days farting around with those bloody covers.