289 Heads 'n' Stuff on '80's 302

[Marauder_63]

• Hey Everyone! Is It Spring Yet??

Had a good session of parts scrounging for the Gee Markee this weekend. Scored a set of freshly rebuilt 289 heads (C6AE) with just enuff miles on 'em to know their gonna work (5K), along with a nice clean & painted 2V intake with all the fittings, spacer, etc., topped with a Holley reman. 2 bbl. carb (its still got the "Tested by ____" & Part # stickers from Holleyon it!), & a pair of 289 exhaust manifolds (C4OE) that are treated in a cool-lookin' Aluma-Coat finish. All these pieces came off the same ''66 'Stang (I saw it ) that was running on the Saturday before I got there Sunday. Practically warm off the motor. The whole package went in the trunk & over the mountain to home for $200. Still smilin' about that.

So now the fun starts. Gonna swap everything into my '81 GM w/ 302 & AOD. Here's the status of the rig as she sits now: shitcanned the OE Variable Venturi "carb" & all that went with it. Removed all the smog gear from pump to cats (save for the PCV), installed a DuraSpark II disto & module (with a curve kit - more on that later), & had Good Guys Exhaust Specialties make-up a full-length 2 1/2 inch dual exhaust system with H-pipe, a couple of Raptor flow-thrus & turn-downs. Removed the A/C, installed new water pump, radiator, & hoses.

So I know there's a huge bunch of knowledge & experience out there re this swap & I would truly appreciate any & all input, tips, tricks & general advice that you all could offer. Below is a list of some specific issues that I've thought of & want to be sure to do right the first time:

• Heads - pushrod length (the heads were not milled; surfaced only), gasket set (type/brand)
• Intake - gaskets (type/brand, factory replacement or RTV or both), vacuum & coolant fittings threads (thread tape/anti-seize), fittings material (brass/galvey)
• Exhaust - gaskets (type/brand)
• Ports - gasket-matching/smoothing
• Fasteners - replacement (type/brand), threads (anti-seize/sealant)
• Torqueing - stages, re-torque intervals

Also, what kind of compression ratio should I expect using the smaller-chambered 289 heads, & how to account for that when timing & tuning? Premium Fuel?

I just got turned-on to another digital camera (mine went Tango Uniform) so I'm gonna document the whole project with pics & I'll post 'em as soon as I get the camera talking to the PC.

Thanks in advance to all that might wanna contribute to the resurection of another Small-Block Ford in another Big Box.

Oh yeah. I'll have the smog gear & A/C up for grabs soon as I get it clean-up & sorted out, if anyone has a need. Try & get some pics of it up, as well.

[Mercracer]

Start out with a factory length 289 pushrod and see what you end up with. Are you using stock style 289 rockers?
Brass fittings with goop and tape. Get a good FelPro gasket kit and you will be just fine...
You can reuse 80s head bolts as they are not torque to yield.

[1987cp]

Those old heads would use stud-mount rocker arms unless they've been converted to pedestal mount for some reason. Are your studs screw-in or press-in? Also, aren't factory stud-mount rockers somewhat adjustable, allowing lash to potentially compensate for very small incompatibilities in pushrod length? My cam kit intended for use with pedestal-mount rockers included a set of rocker shims, apparently with the idea that these would compensate for height lost if heads are milled during rebuilding.

[gadget73]

yeah, they'll be adjustable but the pushrod length needs to be correct or the rocker contact pattern on the valve stem won't be correct. You can make up a few thou from slight milling or head gasket thickness differences with the adjustment but no gross changes are possible without getting the geometry all buggered up.


gasket set, you should be fine with a standard replacement Felpro set for your car. Just make sure the 'this side up' markings are correct on the HG or it'll have coolant circulation issues.

pushrods I'd guess either stock or stock for the 289. Not sure, you'll have to install a pair and see how it looks. I'd probably start with the originals out of the 302 if they're on hand just to see which direction you need to go.

fasteners, your choice. I used stock boring replacement bolts on mine, but you can use better quality ARP stuff if you feel the need. If its not going to be a boosted or sprayed motor, I seriously doubt you need anything more than stock bolts. Head bolts do get sealer on the ones that pass into the water jacket, I've used ptfe sealant (plumber's putty) on those without issue. I've also used non-hardning brush on aircraft type sealant.

head and intake torque patterns should be in any handy dandy manual, or prob somewhere online. go over the intake 2-3 times when you do it to make sure its all even. The center bolts have a habit of getting loose once you get the outer ones torqued down.

[gadget73]

yeah, they'll be adjustable but the pushrod length needs to be correct or the rocker contact pattern on the valve stem won't be correct. You can make up a few thou from slight milling or head gasket thickness differences with the adjustment but no gross changes are possible without getting the geometry all buggered up.


gasket set, you should be fine with a standard replacement Felpro set for your car. Just make sure the 'this side up' markings are correct on the HG or it'll have coolant circulation issues.

pushrods I'd guess either stock or stock for the 289. Not sure, you'll have to install a pair and see how it looks. I'd probably start with the originals out of the 302 if they're on hand just to see which direction you need to go.

fasteners, your choice. I used stock boring replacement bolts on mine, but you can use better quality ARP stuff if you feel the need. If its not going to be a boosted or sprayed motor, I seriously doubt you need anything more than stock bolts. Head bolts do get sealer on the ones that pass into the water jacket, I've used ptfe sealant (plumber's putty) on those without issue. I've also used non-hardning brush on aircraft type sealant.

head and intake torque patterns should be in any handy dandy manual, or prob somewhere online. go over the intake 2-3 times when you do it to make sure its all even. The center bolts have a habit of getting loose once you get the outer ones torqued down.

[1987cp]

Oh yeah, I do really like my Mr. Gasket Copperseal header gaskets. Seal great, and they're reusable. I spray them with a little Permatex Ultra Copper before installation just for good measure. So far the only ARP bolts I've personally used were for the '96 motor I rebuilt, since I didn't want to reuse the torque-to-yield head bolts, and hardened oil pump driveshafts just to be anal about reliable oiling.

[Lincolnmania]

i dont like reusing the head bolts on any 302 cause i've had one broken on a perfectly good running motor.

[1987cp]

Ouch. $40 is cheap insurance against that, then.

[gadget73]

I re-used a set once, before I knew about the possibility of them failing for no special reason. I've heard of it a couple times though, the head just pops off an old head bolt for no particular reason. Not common but not impossible either. That red 86 Towncar that got parted out popped a head bolt while the motor was being cleaned. New bolts are cheap enough that its a "why not" sort of thing. TTY bolts should never be re-used anyway.

[Tiggie]

You'll be looking at a good chunk of compression with the 54cc combustion chambers in those 289 heads. I thought about using them once, since they are supposed to flow as well as E7TE's. I figured up compression using an online calculator once and it came out to about 10:1 if I remember correctly. I can guarantee you're not gonna get a lot of timing advance on that without issues. That's right on the edge for iron heads on using pump gas. You have 8.4 compression right now with 69cc chambers.

You want to get your valvetrain right, if you mix and match early and newer components you risk dropping a valve. 1966 was the transition year when they went from stud-mounted to rail-type rockers. Look at your '66 heads. Do they have close-tolerance holes for the pushrods to go through? Close-tolerance is more of a slot, while the loose is more of a round hole.

The rockers don't mix and match. Look at your 1966 rockers, loose-tolerance will have a little cup over the top of where the pushrod would be (to hold it) while close-tolerance won't have this.
It's also important to note that close-tolerance heads use hardened pushrods. As the others have said, use stock length 289.

You most likely won't be able to use that Holley 2-bbl with a Lokar TV cable kit (or a Ford TV cable). Some have succeeded in modifying the factory TV rod and using a carburetor with the typical Ford A/T kickdown lever.

I've always had good luck with Fel-Pro Gaskets. Get a tube of blue RTV, you'll need that on the area between the front/rear and side intake gaskets.

I'd say use brass fittings on any vacuum or coolant fittings, but you shouldn't need that many.

I can't speak on gasket matching the heads. Opening the exhaust side up wouldn't hurt buy you need to know what you are doing.

Torque Specs:
- Intake to Cylinder Heads - 25 ft-lb, retorque after engine warms up
- Cylinder Heads to Block - two steps, 1st to 60 and 2nd to 70 ft-lb
I'll see if I can hunt down a diagram for ya.

[Tiggie]

Here ya go:

[Mercracer]

You want to get your valvetrain right, if you mix and match early and newer components you risk dropping a valve. 1966 was the transition year when they went from stud-mounted to rail-type rockers. Look at your '66 heads. Do they have close-tolerance holes for the pushrods to go through? Close-tolerance is more of a slot, while the loose is more of a round hole.

The rockers don't mix and match. Look at your 1966 rockers, loose-tolerance will have a little cup over the top of where the pushrod would be (to hold it) while close-tolerance won't have this.
It's also important to note that close-tolerance heads use hardened pushrods. As the others have said, use stock length 289..

ALL early small block heads including 289/302/351W used stud mount rockers until 1977ish... The style of the rocker arm changed in 1966 to a rail style arm which still mounted on a stud and is held down with a nut. The rail style rocker is considered valve stem guided. What you can not mix is the style of valves with the style of rocker in addition to using non rail rockers only in early heads. If you run rail rockers with an early set of valves which do not have the extended stems/caps you can pop the keepers.

You most likely won't be able to use that Holley 2-bbl with a Lokar TV cable kit (or a Ford TV cable). Some have succeeded in modifying the factory TV rod and using a carburetor with the typical Ford A/T kickdown lever...

DO NOT try and use the Ford AT kickdown lever!!!! Don't even think of it!!! The geometry is not even close.

Torque Specs:
- Intake to Cylinder Heads - 25 ft-lb, retorque after engine warms up
- Cylinder Heads to Block - two steps, 1st to 60 and 2nd to 70 ft-lb
I'll see if I can hunt down a diagram for ya.

Torque your heads in 3 steps. 50, 60 and 70.
DO NOT tighten your intake to 25 ft/lbs in 1 step. 1st step 15-17 and the 2nd step 23-25 keeping light of 25 if possible. It is advisable to NOT torque them to 25 and above. You can kill a head gasket that way... The intake actually lifts on the head when you over torque it....
Once the intake is torqued down, torque the top row of head bolts to 75 ft lbs. This will help your head gasket stay put and help keep your intake gaskets sealed also.

[Marauder_63]

Thanks for all the input,guys - that's why I love this site.

Yeah, I didn't even think about valvetrain stuff until I got everything home. Maybe all the studs stickin' up out of the 289 heads shoulda been my first clue. Guess its been too long since I replaced valve cover gaskets on the '81 to remember what it looks like under there.

So what I've ended up with is a pair of "late" '66 (date code 6H16) loose-tolerance heads, set up for rail-type, stud-mounted rockers. Casting # (C6AE) indicates the application was Ford full-size. They came with valves, springs & retainers installed, but no pushrods or rockerarm assemblies. And like y'all have said, '66 valves & springs won't go with '81 pushrods & rocker arms, so I'll have to buy those parts new. So what would be the best approach here? Would going with 289 pushrods & the rail rockerarm be the simplest? Is there enough adjustment available at the stud, to compensate for any difference in cam & lifters between the two applications? It would seem that the camming in a '66 Ford full-size would be close to an '81 Merc full-size, but with that many years difference & the emissions controls factor, is that a safe assumption? Given enough specs for all the parts in play, for both the years in question, I suppose I could figure it out. I'd hate to get close on the specs, buy the parts, & then find out

[Marauder_63]

Thanks for all the input,guys - that's why I love this site.

Yeah, I didn't even think about valvetrain stuff until I got everything home. Maybe all the studs stickin' up out of the 289 heads shoulda been my first clue. Guess its been too long since I replaced valve cover gaskets on the '81 to remember what it looks like under there.

So what I've ended up with is a pair of "late" '66 (date code 6H16) loose-tolerance heads, set up for rail-type, stud-mounted rockers. Casting # (C6AE) indicates the application was Ford full-size. They came with valves, springs & retainers installed, but no pushrods or rockerarm assemblies. And like y'all have said, '66 valves & springs won't go with '81 pushrods & rocker arms, so I'll have to buy those parts new.

What would be the best approach here? Would going with 289 pushrods & the rail rockerarms be the simplest? Is there enough adjustment available at the stud, to compensate for any difference in cam & lifters between the two applications? It would seem that the camming in a '66 Ford full-size would be close to an '81 Merc full-size, but with that many years difference & the emissions controls factor, is that a safe assumption? Given enough specs for all the parts in play, for both the years in question, I suppose I could figure it out. I'd sure hate to get close on the specs, buy the parts, & then find out it wasn't close enough when its all put together & time to adjust the lash. Am I making this way too complicated? Oh well. At least I've learned to think about doing it right, instead of wondering if I did it right.

On a slightly different note (though one that could make the whole preceeding discussion irrelevant): 10:! on the compression?! I was figuring someplace closer to 9.5:1 or a shade less. I maybe I didn't look at late-model enough 302 chamber sizes & was going off 60 cc's (and 8.0:1 for mine now - got that figure somewhere). When I stop again & think about it, the main reason for wanting to go with the 289 heads wasto raise the compression, since I figured thats where most of the power went out of the 302 when the emissions era started. Plus the better flow, plus the lack of Thermactor plumbing or the need to plug it. Plus, I just like the irony of installing factory parts that are older than the car & getting better performance. But 10:1? On today's gas? With 100K on the rings?!

Gonna have to do some double checking, price some parts, & give it all somemore serious thought.

Can't tell ya how much I appreciate you guys' help. Keep ya posted.

[Lincolnmania]

blue rtv is bad mkay
i prefer ultra black or ultra grey or the right stuff (comes in a squeeze cheese can) never had a leak yet