Signet-ficant Other

[Dr.Jass]

I started messing with the closed-chamber heads last night, just to gauge what parts are needed to get them up and running. It got ugly pretty quickly.

I checked my installed height using the old steel retainers from the heads currently on the engine. I can't use those, because it turns out a 1.460" OD valve spring does not exist anywhere the recommended spring rate of 566lb/in or greater. I need retainers similar to what's currently on the engine (1.550" diameter). That's OK because I already own those and they're titanium. The problem is I no longer have access to the retainer measurements. I ordered them by specification five years ago. The records thereof are long gone, and I can't remember if I got extra offset for greater installed height, which was a huge issue with the too-short valves. The installed height of the new heads is ~1.850" (varies a little per valve).

If my existing retainers are standard, I could theoretically shim the valve springs in the old heads .060" to get near their recommended installed height of 1.800". I have to pressure-test them, since they've been installed at a much-lower height for several years. If they don't check out, they're about $150 to replace.

If the retainers are offset, I either find different retainers or step into the world of truly-expensive valve springs. The cheapest ones I've found at a greater installed height are over $350. It's a financial wash between those and new Ti retainers.

There's only one way to find out: I've gotta pull one of the heads and disassemble one valve. But I'm learning: before I do any disassembly on the engine, I'm going to set up one of the closed-chamber heads with checking springs and my intended rocker gear to figure out pushrod clearance on a different block. I'll use the roller cam that came out of the engine. If they clear--or can be made to--with that monster's additional .082" intake/,102" exhaust lift, I'll move forward. If not it's on to Plan B, which currently doesn't exist but may involve a cam change, re-valving the existing heads, or seeing exactly how much cam my Econos can take. The engine they were on had a .528" lift solid, so my only concern is coil bind. For the moment I just need them to run, not race.

As an aside, I'd forgotten how much I hate shopping for valve springs. I also discovered that my math was off; over-the-nose (max lift) pressure on my current springs is 596lb. Weeeeee!

 

[Dr.Jass]

So far, so good.

Bolted together with checking springs and all-new DC/MP/Crane rocker gear, the rollers sit well on the valve tips. A sweep test well past my cam's lift shows they won't nosedive off the back of the valve tip. The exhaust looks a bit off here because the rockers were not shimmed and it moved laterally along the shaft. This was surprising to me, as I've since realized these heads have a 15° valve inclination, rather than the 18° of virtually every head designed for a standard block. That's racy shit right there, and yet another plus for using these heads.



Here's a stock '70 318 shortblock with a .664"/.684" lift roller cam and a W2 head. Funny stuff... 'cept this is the block that was originally going to get these heads. Anyhow, check out the massive intake-face cutouts for pushrod clearance. If you see those, you're looking at 48° heads. They're totally unnecessary on a production block since the pushrods are way in the other direction.




With both lobes on the base circle and me holding the intake pushrod (left) hard against the casting, this is the horizontal misalignment. Well, that doesn't look so bad... hell, the exhaust pushrod looks about perfect.




In the vertical, so to speak, is where it gets ugly. Both pushrods are hard against iron in these photos.






Still not so bad, right? Don't worry, it gets worse.

At maximum lift, the intake pushrod goes hard against the bottom of the pushrod hole on the left, and against the top of the pushrod hole on the opposite side. The top-side interference will solve itself--once there's sufficient bottom clearance, the casting won't force the pushrod to this angle.
NOTE: For those of you not around during the initial build, I gained a lot of insight and experience into pushrod geometry, clearance, and dynamics while making the old heads, uh, work. You're welcome to go back and review, although only the Cliff Notes version is here--the whole agonizing story was on my now-defunct Facebook account.




Detail of where the pushrod cup is at max intake lift. The bottom of the head casting pushes it to an angle that moves it even further from the adjuster. There'll be plenty of room up top once the bottom's sorted.






Can they be made to work? I think so. The main potential failure point is the proximity of the pushrod hole to the intake port. While most of the required grinding will be directly opposite the intake face of the head, there will be quite a bit required toward the intake port itself. Unlike the older W2 heads, these actually do have a bit of a hump in the intake port to clear the pushrod hole--sort of like production heads, but far less severe.




Gauging it with my calibrated finger and thumb, there's about 5/16" of meat there, which should be plenty for the required grinding (although I've been warned it can get pretty close). Come porting time, most of that intrusion can actually be ground away--about the upper 2/3 of it. One nice thing about using the old cam is that once it clears that, there's no question it'll clear what's in the car.

That's where I left off for the moment, as I'm having some pain in my right shoulder and it got to be a bit much. I'm almost convinced this can (and will) work, but I'm not going to take off the old heads until I know it will.

I did attempt to address potential Plans B while I was out there. I pulled one of the valve springs off my Econo heads to check the installed height, which was 1.710". This would've allowed me to use the springs on the old heads, but the retainers on the Econos are only 1.330" diameter. Worse yet, the locks on those valves are 4-groove OE parts, which will not work with the 1.550" retainers currently on the engine (wrong angle) nor my lash caps. I'm almost sure the right locks and/or retainers do not exist, and if I'm going to change valves I might as well continue fighting the heads currently on the car.

I guess the next step is grinding. I hate grinding, but it's par for the course on this engine.

 

[69.5CUDA]

swapin the heads is the only logical thing to do, it gets you back tward rolling, and puts them on a bench where you can run calculations till your blue in the face and figure out the what where and whyfor oto make em work, then you can swap em back on the car and not be in the pit of despare

 

[Dr.Jass]

swapin the heads is the only logical thing to do...

Yeah. It's unfortunate that it took me so long to realize that. Those 15° heads have been sitting in my living room for, I dunno, three years? I've should've come to this decision way back when things initially went sideways early in the summer. Due to non-car-related events, the car wasn't getting to the track this year anyhow, but at least it would've run.

Realistically, the car should be faster with these heads after some light port work. Bigger valves, more compression, 25 years of port development since those 810s were cast, etc. Plus, there's a good reason shallow-angle valves are usually only found on exotic race heads (although B/RB heads are native 15°). 18° valves--a.k.a. standard LA--were the domain of mega-budget Chevy heads (NASCAR, etc.) for a couple of decades. Side bonus: It actually improves my valve-to-piston clearance, although probably not enough to run 1.6:1 rockers.

 

[Dr.Jass]

As mentioned in the "review" thread of the Foredom, I got after the cylinder heads yesterday... well, one of 'em anyhow. I had a pretty good idea of where the most material needed to be removed based on the interference I was seeing. To be honest, I probably overground the holes a bit, but in the directions that I was grinding I my concern about port intrusion wasn't fully warranted. Mike at B3 Racing Engines had mentioned that he didn't know if using 48° heads on a 59° (stock) block was possible; he thought the clearancing would hit the intake port. He was not in any way saying it definitively, he geniunely didn't know.

They can. This is gonna work!






As it turns out, those pushrod bulges pictured in the last progress post are there for the 59° heads, not the 48s! I discovered this while researching porting. Dulcich ported a set of 59° heads for Hot Rod online awhile back, and he had to leave some of the pushrod bulge in place because it was that close to the pushrod hole. On my heads, there's a ton of room there, and since I know my combination I don't need to hog the holes anywhere near the amount Chrysler did (technically, mine are probably larger but they're much further from the port wall). Plus, as the lifter rises, the pushrod moves away from the offending iron, so as long as there's even 1/32" clearance, it won't hit as the cam rotates.

Clearance can be a hard thing to photograph, but I tried. In the first photo, the yellow delineates the pushrod hole while the red is the edge of the pushrod. The photo from underneath is deceiving; I could easily put 7/16" pushrods in it and have no issue. Also, I believe the head gasket will add a scosche more clearance; I didn't use one during this process because my chosen Mr. Gasket .028"-thick gaskets are very sticky and no fun when you're installing/removing the head repeatedly.








How much did I grind? Here's a couple of side-by-each photos showing what I removed. The first shows the pushrod holes for #1 and #3 after #1 was finished. The second shows the two exhaust pushrod holes on either side of where the heat riser passage would be on production heads.

(Damn, I need to ease up on the snacks...)




Each pair of ports was checked on the 318 That Should Not Be after clearancing. Once all eight holes cleared, I went back with 60-grit sandpaper rolls and polished all my work. Musn't leave stress risers!




I should mention that none of the cutouts on the intake face is any larger than it was when I started. All the grinding was in the opposite direction. 11° of additional lifter tilt really makes a huge difference.

One potential problem with all this occurred to me, and while I don't love it it's a fact of life and I'll deal with it. Because the valves are inclined less, the valve cover gasket surface is actually clearanced for the valve springs.




It's not the potential leak factor that concerns me, it's the fact that the stock 1969 valve covers probably won't clear the valve springs! By the unwritten law of The Valve Spring People, springs in the required rate simply don't exist below 1.550" diameter, and with the retainer installed they're very close to 2" tall. Look at the angle of the valve spring seat, then consider where the valve cover will be. If they clear, it'll be re-he-heally cozy. I have a set of fabricated covers that should work, but they totally take away from the look for which I was aiming (and used to have). Of course, one upside of this swap was mentioned by @Stretch today: "Maybe this time you'll remember to grind 'Holley' off the intake!"

The real upside of this arrangement? I have newfound confidence in this engine. I know these heads will work because I'm using parts designed for these heads by the people that invented them. Everything aligns and fits. No hokey-ass backyard bullshit (although I am still working in the backyard). Not only that but with the increased compression, 15° valve angle, and larger valves these heads should make more power than the old ones would've, ginormous ports be damned. Considerably so, in fact, especially if I port them... and that's looking more likely, because after using the Foredom and genuinely enjoying it, I was eyeballing those bowls pretty hard yesterday.

Most of all, though, I'm excited about this engine again. That's something I haven't been able to say for about a year, and this time around there's much less fear of catastrophic failure hanging over me.

Stay tuned!

 

[69.5CUDA]

since you love gods dremel so much, im going to throw out a wild sugjestion that you might like considering the look you want

what about getting a generic cheep set of CAST aluminum valve covers IE mp, holley, eddy, cal, etc and grind all the crap off then shoot em to "look" like tin covers?..the sleeper look with the sealability of aluminum while getting the clearance?

 

[Dr.Jass]

I actually have cast covers, but there's less clearance on those than there is on the OE units due to the material thickness. I don't need height, I need width--the problem is the angle of the valve springs, not the overall height (which the stock covers would clear). The fabricated covers are thin sheet aluminum welded near the outside of the flange.

 

[69.5CUDA]

i know youve got "pristine" set of steel covers any chance you can score another set and "dimple" them? or even cut them free dimple n re-weld.....i know how much your trying to keep the "stock" look going

just kinda thinking outloud

"some" of those cast covers are really thick but probably not thick enough for said clearance eh?

 

[Dr.Jass]

i know youve got "pristine" set of steel covers any chance you can score another set and "dimple" them? or even cut them free dimple n re-weld.....i know how much your trying to keep the "stock" look going

That's exactly what I've considered doing. The trick is they need to be dimpled from the inside out. I thought about taking a chunk of wood or metal, making the desired exterior shape of the dimple, and using a very small hammer from the inside (or a length of wooden rod) to hammer the side of the cover into the mold for shape. The problem, of course, is that it may pull the flange out of shape. Before I get too far into that, though, I want to assemble a couple of valves and see where I stand. They might clear--the heads will accept something like a 1.700" diameter spring (wider than the installed height of a stock 340 spring--oy) so it may not be an issue a'tall.

 

[Dr.Jass]

I spent 2½ hours in the garage tonight grinding. I intended to stop at 9PM but kept after it for another 45 minutes because I didn't hate what I was doing. The first hour and fifteen minutes were spent clearancing the other cylinder head for pushrods. Once you know what you're doing, it goes pretty quickly.

That fully accomplished by about 8:30, I just couldn't stop myself. Yeah, I just need it to run but damn it, it might as well run fast.

Before:






....aaaaand, after:







Mind you, I've done nothing to the port runner whatsoever, I just did bowl porting. It's actually not as extensive as it looks--I didn't try to reinvent the wheel here. I simply blended the plunge cuts that my machinist made with the seat cutter to a smooth transition and smoothed the guides. I also made sure any transition was a smooth radius rather than angled, then went in with the sandpaper rolls and did a preliminary polish on them.

The only reason I stopped was because I had to come inside to make a phone call. Left to my own devices, I probably would've stayed out there another hour and a half, and would've gotten another couple of bowls done. It goes so much more quickly when you're not constantly waiting on the compressor. It's easy to be motivated when you know you won't be standing around idle half the time you're out there.

 

[Dr.Jass]

I went out to the garage to fetch something earlier, and quite unintentionally ended up being there for 4½ hours.

The first cylinder head is done. All clearancing, porting, and polishing is finished. I was able to completely remove the pushrod intrusions without the iron even getting thin, much less frighteningly so. There are additional intrusions closer to the bowls for head bolt clearance; I cleaned and smoothed them a bit but ran out of testicular fortitude. I also ground out the sharp edges between the valve seats to eliminate potential hot spots.

Someone already had their mitts on this head--one chamber and its attendant ports were already smoothed but not ported/polished. I don't think I want to finish what they started and polish the chambers. Well, I do but I want to get these done and back on the car--not turn this into a winter project.

The intake manifold came off the car Thursday during a lull in the afternoon--my guest wanted to go drinking and I didn't care to tag along. The old heads have to come off so I can use the locks and retainers on the new heads. I might get the other casting fully ported and polished tomorrow, I probably won't finish the heads until sometime during the week. We'll see how I feel--I'm pretty beat and sore from bashing around the junkyard Friday.

As I sit typing this, it occurs to me: I completely forgot why I went out to the garage in the first place. Oh well, it'll come to me eventually.

 

[69.5CUDA]

As I sit typing this, it occurs to me: I completely forgot why I went out to the garage in the first place. Oh well, it'll come to me eventually.

youll remember mid polishing
LOL

 

[Dr.Jass]

youll remember mid polishing
LOL

I actually remembered this morning. Now if I can get to that job rather than starting on the other cylinder head, I'll be in good shape.

 

[Dr.Jass]

I got the other thing done, which required the air compressor. Every time I had to wait for it, I polished a chamber... let's be honest: We all knew I was going to do that.

 

[Dr.Jass]

I unbolted the headers from the engine and realized the headers had to be disconnected from the exhaust to go any further. Further examination proved me wrong: They have to be completely removed from the vehicle to get the heads off. I think I can maneuver the driver's side head around the master cylinder, which would not be the case with power brakes. The booster would absolutely be in the way. However, the new heads use two long bolts rather than the single long one used by standard LA/early W2 heads. Problem is, I have head studs instead of bolts, so I may have to move the master cylinder to get over the (new) longer stud on that side.

I'm a firm believer in head studs but they do add complexity to otherwise relatively-simple tasks.

 

[69.5CUDA]

whats your reasoning on head studs over bolts, im genuinely curious...specificaly as ive had more studs break than i car to admit...i assume its better claming force and the fact that "useualy" the nut will fail and just unthread the stud...do you treat the stud with anythng when you stick it in the head?

 

[Dr.Jass]

Head studs have stronger, more-consistent clamping load than bolts. When you tighten a bolt, the greatest load on the bolt is at the top thread, with less load as you travel away from the head. With a stud, the fastener stretch--which is the reason for a torque specification--is spread out evenly among all the thread because they're all fully engaged before you begin to tighten. That equalized load means the stud can withstand a greater installation torque. The recommended torque for the stud kit I have is 110lb/ft, 15 higher than OE 340/360 and 25 more than 273/318. More importantly, it's 10lb/ft more than ARP's own equivalent bolts for the same application (W2).

With only ten bolts per head (four per cylinder) clamping load is especially important for cylinder sealing. The best example I've seen of this, not surprisingly, is the 6.0L Ford Powerstroke. Studs more than double the life expectancy of the head gaskets beyond the same gasket installed with new Ford bolts. A modification as simple as a tuner (Bully Dog, SCT, etc.) will seriously lower the gaskets' life span. On that particular engine, studs aren't an option--they're literally a necessity. I have a (relatively) high-compression engine with 10-bolt heads that will see fairly silly RPM often. A blown head gasket can destroy the engine; studs are cheap insurance. B/RB engines (and small Chevrolets) have 17 bolts per head (5 per cylinder) so they naturally have a better distribution of clamping force. I probably won't stud my 440; it's simply not as much of an issue. On the other hand, I probably will stud my Challenger engine just for the extra durability. Everything else about that engine is overkill for a pump-gas street engine with low-9s compression: block fully race-prepped, main studs w/girdle, forged crank, aftermarket rods, etc. The block machining alone was a grand. Why shortcut it at this point?

The ARP studs install with their moly lube (the instructions often supply a different torque spec if you use motor oil instead of the ARP stuff), as do the nuts and washers which need to be lubed at their mating surfaces, including to the head. The studs have a hex socket in the end and are installed to their own (low) installation torque spec (the bare stud into the block) to pre-tension the block and keep them from backing out with the nut.

Obviously they have their down sides as well, including the situation I've got, but ultimately they're still worth the effort. Despite my best efforts to the contrary, there's a lot tied up in this engine now and some of it is virtually irreplaceable.

 

[69.5CUDA]

ok gotcha for some reason i was only thinking in terms of exhaust, but..now even more of it genuinely makes sense as i never got the higher clamping force since well, threads are threads and my assumption the weak point of ANY fastner is the threads as they are both a stress riser andd the thinnest point, studs to me just gives you double the points at which to break..but i get it now

still on the exhaust side of things, is studs still better there as well?..bikes get em pulled out by the bucket full, nuts gall up under the heatcycling water and rust and pull the studs often times destroying the head when service is required, alfa seems to have solved it by running brass nuts on the headers

 

[b-body-bob]

Every time I had to wait for it, I polished a chamber

If it takes that long to recharge you either need a bigger, better pump or a smaller tank.

 

[69.5CUDA]

If it takes that long to recharge you either need a bigger, better pump or a smaller tank.

i solved it by going HUGE tank and massive v-twin pump, i can run everything full tilt...even the blasting cabinet..big oll early 80s CH "commercial" unit...wish id done it ages ago

tho i did have a modified job site lil roll around twin tank that had been modified for painting cars by its previous owner..bigger pump, with a modified valve, as soon as the psi dropped by 1-2 it kicked on, yes..it ran and ran but it could keep up with ALOT of work ..much more than it should have