What are the differences besides the center bolt valve covers?

What is different about the intake manifolds?

 

On cast iron heads, the center two bolts for the intake manifold are drilled/tapped at a 72° angle instead of the 90° angle as on older heads.

Also, the push rod holes are sized for clearance, instead of being sized and positioned to guide the push rods through the holes. This is why '87 and later SBCs require self-aligning rocker arms (or guide plates for modified engines). Aside from that, the cooling passages, bolt hole locations, valve angles and positions, etc., are all the same. Most '87 and later heads have better port designs than you'd find on some earlier heads. The EGR provision exists on all cast iron heads except the LT1s - which are a different story entirely.

 

What he said, except for the "better port design" part.... the wonderful "swirl port" TBI heads are included in the post-87 lineup, and should be avoided as completely as 70s smog stuff or 60s ones with no accessory bolt holes. The only ones that are any good for anything, as far as Gen 1 SBCs, are the TPI heads (LB9 and both the cast-iron and aluminum L98 ones). All the others, which include truck heads, Caprice L05 heads, L03 heads, etc., are garbage.

 

I drilled my intake so that it will bolt up, but I would still need a set of self-aligning rockers or guide plates right?

 

Yes.

 

Guide plates are a lot cheaper, and I already invested (a few years ago) in a set of roller tip rockers that are non-self-aligning.

Any set in particular?

EDIT:

Stock push rods are 5/16's?

These work?

Again, I'm showing a small portion of my vast ignorance.

 

Guide plates may be cheaper to purchase, but you need to consider the head preparation cost to be able to install them. The heads need to be removed and the stud bosses machined lower to accet them without affecting valve train geometry. The prices of fully rolerized self-aligning rockers are coming down.

 

O

The vast expanse of my ignorance is overwhelming!

I thought the 87 and up heads were all prepped for the guide plates. I obviously haven't looked to check. Maybe I'll get lucky......I'll look when I get home.

 

If they were already prepared, you' have stud bosses machined about 0.325" lower than the old "standard" height, and screwed rocker studs, not the factory "pull-out" studs. We're pullin' for ya. Maybe you'll be lucky.

 

Well I know they have screw-in studs. They are World S/R Torquer heads.

Before I got these (used) I wasn't even aware that they came in the 87-up configuration!

So how would I tell now?

 

Since the center 2 bolt holes on the 87-up style aren't perpendicular to the surface, they're usually pretty easy to spot.

But since they're not stock heads, they should already be set up for reasonable lift like .500", and should encounter no interference issues.

And since they already have guide plates, you must not use self-aligning rockers. The 1418s you asked about would work fine.

 

Well, you never mentioned that they weren't stock heads... Slap me for assuming again.

What engine are these going to be bolted to? Their gasket recommendation for 305s has some significant asterisks behind it. And I thought that most World heads are set up for both center and perimeter cover bolts.

 

The 305 torquer heads are being slapped on my L69.

These heads are only set up for center bolt valve covers. The intake bolt angles for the 4 center bolts (2 on each side) is different than the older style, but I've already modified my intake.

 

The 305 torquer heads are being slapped on my L69.

These heads are only set up for center bolt valve covers. The intake bolt angles for the 4 center bolts (2 on each side) is different than the older style, but I've already modified my intake.

RB, they don't have guide plates. I'm not sure if they originally came with them or not. I asked the original owner, but haven't heard yet.

What I'm hoping is that I can buy a set of guide plates and just slap them on. They do have screw in rocker studs, but I don't know if I can just bolt the guides on a roll. Anybody know off hand if 87 and up torquer heads come prepped for guide plates?

 

why don't you just give world products a call?

 

Well, according to the tech data on the World Casting's website, they are NOT machined for guide plates.

Just to see how much the cheap stock replacements would be from a chain parts store, I called and they wanted $10.99 a pop! Whoa mama! Why so much more than the non-self aligning?

What makes these so much more expensive?

 

It might be cheaper to go the guide plates route, than buying a set of decent (NOT stock replacement) SA rockers. Which also leaves you with an upgrade path for the future.

Odds are, if there's screw-in studs in there now, and they're the kind with the hex drive, then they're actually set up for guide plates. Call World (Dart) and find out.

 

World Castings is now located in NYC, not Michigan. The last time I worked with 305 Torquer S/R heads, their instructions indicated the need to use 350 head gaskets on a 305 due to clearance and exposed gasket in the chamber. After a long conversation with two of their engineers, I discovered that they based that information on whatever Fel-Pro gasket number they happened to look at. Using a new GM head gasket revealed that there would be no intrusion and clearance problems, since the GM parts are constantly revised and upgraded while Fel-Pro continues to use the same old dies.

As for the two center bolts on the intake. even though you drilled the holes to elongate them, getting the correct bearing and pressure distribution from the bolt heads will require you to either machine the intake where the bolt contacts it at an 18° angle, of use tapered or equalizing washers to distribute the load correctly. 3/8" tapered (structural) washers can be found at MSC (P/N 67494849) for 44¢ each. These are a little large, and may need to be trimmed to fit. Equalizing washers (MSC P/N 00099010 - $4.25 each, McMaster P/N 91944A030 - $4.13) may cost a little more, but are a lot smaller and automatically center the bolt and distribute the load. I'd hate to see you stress and crack your intake.

 

Thanks for the part numbers Vader.

I am considering purchasing a new, correct, intake manifold, but I'm on a budget and don't really want to spend money for the rockers and intake right now.

I've got it figured out now, finally. Thanks again for all of your help.

I'll be buying a set of self-aligning, roller tip rockers for now. Funny how "deals" always turn out isn't it?
And as usual, it was certainly NOT the seller's fault, it was my own.

 

O.K. - I was mistaken. They're now up to $4.50 each:

 

I think I'm just gonna bite the bullet and buy the intake I want anyway. I plan on upgrading from my current intake (Weiand Action Plus) in the future, so why not do it now while everything is apart anyway?

 

Don't tempt <i>me</i>!