Roller Rockers vs Explorer Valve Cover

[cgrey8]

I put the RRs on the engine just to see how they sat.




On a sidenote, I was surprised by how smooth the stock rockers move on the pedestal. I thought there would've been more friction. But I guess these engines couldn't get 200+kmiles from the stock build otherwise. Although with stronger springs and higher lift, I expect the friction would be greater and likely would wear the rocker more.

And there is interference with the Explorer valve covers...some of the places you could predict. But there was an interference I didn't expect. Here's the details...

The predictable place to have interference, seeing the above, is at the valve end of the rockers. And sure enough, there is interference:



The good news is some risers to lift the covers off the heads would probably fix this. Notice:


The interference I didn't expect is on the side of the outside rocker:



Here's a comparison of the RR to the stock rocker:



To solve this one, I expect I'll have to grind the side of the rockers on the ends of the head so it doesn't interfere unless anybody has any better ideas. Fortunately there appears to be plenty of aluminum material there to grind away. I can't see any issues with doing that. The other option would be to cut out the side of the valve cover to make clearance and weld something in its place. I like the idea of grinding on the rocker better.

Thoughts? Am I on the right track? Anything additional anybody can add?

[Grumpy]

i BET you will still have another problem even if you do grind off the edges of the RR's .. and that is the top of the rocker where the push-rod sits .. try this....... put them back on ... the Rollers .... and then set the valve cover on it and rotate the engine over with a ratchet and socket on the crank pulley bolt and watch the valve cover rise up as the valve opens..... make sure you turn it over a full revolution or two to make sure it raise's the valve cover or not ..... i bet it does.... cuz.... i did the same thing on my 5.0 .... had to swap out the valve covers for the "tall" ones .. good luck and let us know

[MalcolmV8]

I would never grind a rocker! but that's just me. I go to great lengths to keep all the parts as balanced and equal as possible. Not to mention if the manufacture could build the rockers lighter and smaller with less material and still maintain their strength and integrity they probably would. I'd modify or replace the valve covers most definitely. Others may have different opinions on that.

[cgrey8]

i BET you will still have another problem even if you do grind off the edges of the RR's .. and that is the top of the rocker where the push-rod sits .. try this....... put them back on ... the Rollers .... and then set the valve cover on it and rotate the engine over with a ratchet and socket on the crank pulley bolt and watch the valve cover rise up as the valve opens..... make sure you turn it over a full revolution or two to make sure it raises the valve cover or not ..... i bet it does.... cuz.... i did the same thing on my 5.0 .... had to swap out the valve covers for the "tall" ones .. good luck and let us know

If it is interfering there, I can't see it. The other interferences are too great for that one to be noticeable. I did turn the engine over and get both valves to exercise with the valve cover sitting on the rockers. The cover lowered as the outside (exhaust) rocker moved down. It eventually just rested on the other (intake) rocker until it started to move down. When the exhaust rocker moved back up, the cover was back in the same place. But you may be right, there could also be an interference at the back of the rocker. However I suspect/assume that if I rise the cover up, that'll solve top-interference issues on the front and back. What I'll have to test is to see how it behaves with a larger lifting cam. The stock Explorer cam lifts to .421"/.447". The cam I'm planning to use will lift to well over .500" (at the valves).

So the plan now is to get a better picture of what I'm dealing with. Since these valve covers are junk anyway, I'm going to do some cutting and grinding on them. The 1st thing I want to do is clearance away the cover on the side edge here:


I'll start by seeing if I can just grind a channel through the cover without penetrating it and get some clearance. Based on how much deflection there is of the cover over the bolt holes, I don't see that actually happening. So I fully expect I'll have a "blowout" on the side of the cover. But if I do, that'll let me see the rocker, while it is moving, so I can see just how much it is interfering. That'll give me a better idea how much metal I'd have to remove from the rocker OR how much clearance I need from some other solution. Next, I can cut the valve covers in thirds so I can put each end of the cover over the rockers and see what is happening as I spin the crank. Doing this should give me a clear picture as to what is and isn't going to work.

Now lets assume that raising the covers up by say .330" with thick "riser" gaskets will give me the clearance I need across the top of the cover. That just leaves the end rocker clearance issue. Obviously I could just replace the valve covers with something else. But I really don't want to do that for a few reasons. For one, the oil hole would be buried forcing me to remove stuff off the engine to get access to it to fill the oil. And the filler snorkel that Ford puts on these valve covers also serves as the inlet for PCV intake air.


Notice in this pic, the riser comes up off the valve cover and has the oil cap up where it is accessible. But more importantly, the rubber inlet hose that routes over to a 1-way valve I snagged off of a brake booster. As the PCV valve relieves into the intake plenum, the vacuum created in the engine is relieved via that rubber tube. The tube must be pulling air from downstream of the MAF so the EEC is aware of the PCV air going into the engine and can compensate for it.

And the other reason I am resistant to go with a tall valve cover is the clearance issue with the AC Box. When I made that mod, I chunked out only as much as I needed to.


Raising the valve cover slightly hopefully won't cause any problems, but a radically higher or differently shaped valve cover could. If I have to revisit the box, I will. But I'm just trying to consider all options that allow me to reuse the Explorer valve covers since reusing them solves multiple problems that would have to be solved in different ways with a different valve cover.

What about cutting a clearance hole in the valve cover I plan to use? What can I cover the hole with? If I had a welder, I could weld something like a piece of angle iron over the clearance-cut up but that's not likely to be pretty at all since I'm not a seasoned welder or fabricator. Although when the engine is installed in the engine bay, none of the valve cover corners are easy to see. So pretty isn't really a high priority to be honest. But what about keeping the modification sealed? If I go really liberal with the silicone gasket on the inside of the valve cover, that might work.

I also thought about fiberglass. Cut a hole in the ends of the valve covers, the put a layer of fiberglass on the inside and outside. They would hold each other in place, then again with the silicone gasket to keep it sealed. But I don't know how well fiberglass holds up to heat. I wouldn't think there'd be a lot of flexing going on at the valve covers, but there are vibrations. How well would the fiberglass handle that? And how well would the resin tolerate motor oil?

Neither of those ideas are elegant. And I can't help but wonder why Ford made the Explorer valve covers narrower in this region to start with. Notice in the 1st pic of this post how much further the cover comes in from where you can see the gasket went. It makes me wonder if they purposely did this to the Explorer valve covers to make room for some accessory, hence replacing the valve covers or creating some custom clearance as described above would actually prevent me from using the Explorer accessory brackets. Anybody aware of issues using Explorer accessory brackets with other valve covers? If there are no known issues, then it was likely just cheaper to stamp the covers out like that.

All of this thinking makes grinding the corner off the edge of the 4 corner rockers a more and more attractive fix particularly given this isn't going to be a 6000+RPM screamer...just a stronger daily driver that will occasionally see 5500 RPMs, but most days won't go over 2500.

[6jeff6]

Rockers take alot of abuse. I wouldn't grind them.


jeff

[cgrey8]

I cut a notch into the valve cover to see just how much interference there is. There's not that much...or not as much as I thought. Check the pics:


Here's a view from the top with the notch opened up a little more to see just how much I'd have to take off of the rocker if I chose to do that:

Round that corner off and problem solved...as long as I'm not creating another by grinding on the rocker.

Here's a view of the rocker at full lift:

It moves right out of the way with lift. It's at worst-case condition at valve-closed.

I found a set of .335" valve cover gaskets on eBay. As long as that gap is less than .335", the gasket should fix the interference there too. I haven't measured it for sure, but it looks like about 1/4" (.25").

So now the question is whether I should notch the valve covers I plan to use. It's a small notch. Now the question is how can I close that hole? Glob layers of welding material on there?

[Dave]

Chris, been thinking about the problem. I think that even grinding off a .100 radius would not be a problem with the weight or strength. Doing the math, you might lose .007 grams in weight. Not to offend you but the more expensive rockers are of a forged design and have smaller cross sections at either end. These you have are basically just a machined bar with the roller bearings in them. You could use a dreamal and cut a very thin slot in the corner of the VC and use a ball peen hammer. Put the outside corner in a bed of sand and carefully use the hammer to open up the slot enough and then get it welded/brazed shut. You are worried about the air box, best check on your existing set-up and check for clearance under the drivers side plemum between the fittings and the VC, gets kind of tight under there.
Dave

[cgrey8]

I agree. And, no I'm not offended. If these were high-dollar rockers, I likely wouldn't have this issue. These are around $200/set new on eBay and compare to Proform's RR set in both quality and cost. I think SummitRacing sells the Proform RR set for $230. I paid $120 for them which isn't bad being these look new with ZERO signs of use. There are actually cheaper brands on eBay that go for as low as $150. I don't know anything about them, but Scorpion rockers seem to be fairly popular.

And yes, these look just like extruded aluminum housings that are machined with the detail they have. I guess its possible they are cast, but either way, the amount of metal I'm looking to remove is not in the load-bearing area. It'll get close, but there's a MASSIVE amount of metal on these things. I just can't see rounding the corners being a problem for a sub-6000RPM application.

BTW, I ordered the thick gaskets so hopefully I'll have them to work with in a few days. Once I know more, I'll post what I find, if anything for my own benefit to look back on years from now. Yall don't realize how much I actually go back to old posts for various details I just can't remember, but remember discussing. I hope the pics are at least somewhat interesting for others to look at. I'm trying to get the best angles I can for still-pics. I know it's not the same as seeing it. Even when I look at MY pictures, the rockers still look bigger in my hand than they do in the photos.

[Dave]

Chris,
Realized after I posted that the weight I mentioned is off by a factor of 16 (lbs vs oz). Something about the medication for the Shingles and Wisconsin pain killers.
Dave

[MalcolmV8]

Chris,

Those slots you cut could easily be welded closed with a patch piece of sheet metal giving you clearance for the rockers. I would make a patch with a bit of a bubble to it and have a shop weld it on for you. It takes some experience to weld thinner metals like the valve cover and even more to make welds that don't leak. Once you start welding I think you'll be amazed at how your welds leak. Making air tight welds is an art and shouldn't be your first welding project.

Good luck man.
Malcolm

[Grumpy]

if i were you .. i WOULD NOT grind on the rockers in ANY fashion ..... i did it on a Chevy with rockers that look exactly like those but were gold .. Crane i think they were .. well.. to make a long story short ..... out of the 6 i had to shape up .. 3 lost the pushrod seats in the rockers and one had a hair line crack in it and it got worse and cracked into the fulcrum area of it and it failed ......... so best thing you can do is use EXTRA thick gaskets or "tall" covers or make an aluminum spacer to go between the cover and the head and put the cover on top of it .... only thing is .... you will need 2 sets of gaskets... one to go under the spacer and one to go under the cover on top of the spacer .... i have seen these too ... they work pretty dam good ...... anyway .. GL and let me know if you need any more input or anything .......... i used to work in 2 speed shops and have seen ALOT of stuff that ppl make that is NOT on the market......lol

[cgrey8]

I looked into just spacers, and those things are like $90 for a set, and as you said, they require a gasket on both sides. The other problem with the spacers is they raise the cover WAY higher than I need. I only need it 1/4" lifted. And those aluminum spacers, by themselves, I think were over 1". That doesn't buy me out of the AC Box mod so I'd be far better off just buying taller valve covers.

As for the grinding, yeah aluminum does tend to fracture-crack if you don't take the time to smooth the surface and remove the places where fractures can begin. That's nearly an impossible thing to do if you are modifying the inside of the rocker or drilling on it. But grinding on the outside, I think I could get it smooth with some fine-grit sand paper. But as Malcolm said, if I can weld up those reliefs in the valve cover, that would be best so there's no grinding on critical parts. The worst the cuts on the valve covers can do is leak. And I think silicone gasket can reduce/eliminate a majority of that.

I'll keep yall posted...

[Grumpy]

another thing to consider with the taller covers is this ..... you cant go to high or they will hit the upper intake plenum on both sides and possibly the TB and hang the throttle open some .... so you will also need a phenolic spacer between the upper and lower intakes to give more clearance for the taller covers which will require longer upper to lower mounting bolts ..... at least 1/2 inch ...... its a give and take situation when swapping to roller rockers .... if you know someone in a GOOD reputable machine shop...... they can take one of the spacers and mill it down to what ever height you need ..... if they are 1 inch .. then you can get two 1/4 inch ones out of it like you need ........ just a thought

[cgrey8]

I can see how valve covers would affect throttle on a Mustang engine where the TB is hanging right over the valve covers. Fortunately on Explorer engines, the valve cover doesn't come near the throttle body arm and cable thanks to the 90° intake elbow the EGR mounts to that locates the TB pointing forward with the cable right over the lower intake.

The 90° elbow doesn't buy me out of upper intake plenum interference though or interference with the elbow itself. But for less than 1/2" increase, I don't think it's going to be a problem. Although that is certainly something I'll be paying attention to. I can also just look under the hood at the Explorer engine in the engine bay right now to see how much space there is. But from memory, it's all good for the modest height increases I'm looking at.

Malcolm, what kind of metal should I use to fab up clearance-covers? I'm assuming just any old sheet of metal, like roofing tin or flashing, isn't going to be the smart thing to use. Not to mention, as small as this opening is, bending metal to fit isn't likely to be that easy even if I used roofing tin. If the metal is thick, I imagine my only option is to use multiple flat pieces welded together at angles to cover the clearance hole. If I can get thin enough metal, I would try forming it around a bolt to get the curve I need, then flare the edges that would be welded to the cover. Weld that on, goop it all up with silicone caulk, then weld a 2nd metal layer on top of that to cover and protect the silicone...and give me a metal surface to paint. The outside layer's welds could leak like a siv, as long as the silicone kept the inner layer's welds sealed. Thoughts?

[MalcolmV8]

On welding the valve covers. I'm not entirely sure I understood the inner and outer layers you were talking about but I think you wanted to weld a patch and then silicon it and then weld a second patch over that one to paint. That will probably not work because when you weld the valve cover is going to get extremely hot. In fact the metal will be glowing red and any silicon anywhere near the weld is going to melt completely off.

You know a very easy method might be to cut the exact locations you need and prop them back in the air so to speak and then have a shop fill the gap with weld there by creating a bubble. I think you need just a hair more clearance than that though.

One thing I've done in the past is take some thin sheet metal and place it on something soft like a bean bag. Take a rubber mallet and hit it hard in a section and dent it to the shape you're looking for and then cut around the bubbled dent and you'll have your bubbled up patch to put on the valve cover. It'll take a few tries, probably many tries if you've never done it, but you'll eventually get what you need. You can always work the metal a lot too. Put it in a vice and hammer away, bend with pliers, heat with a torch and shape etc. You can do a lot of shaping with metal and get just the right patch.

Also I highly recommend a shop weld this for you just for the sake of leaks. They probably won't charge very much and it'll be worth it. The welds will be so clean that after sanding and painting them you won't even be able to tell hardly. However if you want to weld it yourself I'd recommend sealing all the joints with jb weld after wards and then sanding and painting and it'll look good too.

Here's an example of a good weld on a valve cover. Mine had the oil filler tube broken off when I got the motor for my blue truck.