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I have a fairly stock 289, which is still getting hot on the passenger side. I've got the citric acid flush left to try, but pretty sure i've narrowed it down to being related just to that head (whether the passages are all blocked up or something). Judging by the oil condition when i got the car, i dont think the PO was that into changing fluids. :/
Proper cleaning as described earlier is likely all they need to fix that.

Oil pressure is also quite low when hot - at idle, the needle is barely lifted off the stop. It's about 1/4 way up the gauge when cruising, and 3/4 of the gauge when cold and first started.
These gauges are notoriously inaccurate. I'd like to see a real number. Factory spec is minimum 25 psi @ 2000 rpm hot. So, a hot idle would be pretty darn low.

So, im thinking some worn bearing shells probably cause of this. No knocking, but thinking still due a rebuild. Also, get a reasonable amount of breathing out the rocker cover filter.
New bearings would likely cure the problem. Blow-by out the breather is a ring thing.

So, thoughts while i'm at it, is that maybe just replacing the heads is the way to go.
Hmmm… Replacing the heads would not cure low oil pressure or blow-by.

Current specs are:
Stock 289, with Edelbrock Performer intake, and Edelbrock AVS2 500 CFM carb. "High rev" hydraulic lifters, uprated springs (inner & outer), new Cloyes timing set, and changed the cam (which was meant to be a Performer, but got something different - but is about 1-2 levels above stock). Standard exhaust headers, with 2" dual exhaust. Stock C4 trans, and stock rear axle/diff.
The Edelbrock Performer is no better than the stock iron manifold. That carb is fine for a mild cam. High rev lifters are no harm, but no help, since you don't have a high rev setup. I don't know what "levels" means. To me, two levels above stock is the Cobra LeMans cam, which you assuredly do NOT have. Give us some numbers. 2" exhaust is fine if you are not going out on the track. Heck, the 67 GT500 428 dual-quad engine came with 2" exhaust. The C4 is going to need some help with shifting, perhaps the K code shift servo. If you still have the 2.78 rear, it's killing your performance.

Not after anything too fancy - just street use for a bit of fun, and a bit more noise/choppier idle.
Take some advice from an old guy who can still hear. Loud exhaust doesn't make the car faster. It just pisses off the wife, girlfriend, and neighbors. And a choppy idle means the engine was not planned carefully.

Ford's Product Acceptability Standard, or P.A.S, mandated that all Fords, no matter their intent, "must start when the engine is hot, start in cold weather, idle, run in traffic in Fourth gear, and run smoothly at 20, 60 or 80 mph, as well as acceptable noise levels. In other words, cars sold to the public must run just like a Lincoln Continental. In addition, the P.A.S. demanded that the engine compartment, passenger compartment, and overall noise levels must not exceed a certain maximum."

This included the 427 cid 2-4V overhead cam engine. You planning more power than that?

After suggestions, please, for suggested mods?
I just did a port-matching job on a pair of K code heads, and new repro manifolds to go with them. Since it's a K code engine, he needs no advice. You don't have a K code. So, I'll give you this:

While I have the C3OZ-6250-C mechanical cam in my own car, mechanical cams are not for everyone. The C9OZ-6250-C hydraulic cam provides very similar performance.

For this upgrade, you will need:

C9OZ-6250-C camshaft

Cobra or Performer RPM intake manifold

Autolite, Summit, or Edelbrock 600 cfm carburetor

14" open air cleaner

Distributor recurved to BOSS 302 specifications

Dual valve springs (recommended)

Screw-in rocker studs (recommended)

Heads port-matched to exhaust (or aftermarket heads)

289HP exhaust manifolds or headers

This combination has been dyno tested at 323.5 hp @ 5300 rpm.

Nothing else is required. No whiz-bang million volt coil, 10mm wires, etcetera.


· Registered
37,735 Posts
There are two items that are set in stone in the vintage class of road racing these old clunkers. Iron heads that are either year correct or some use the more modern iron heads. The other is using the old school dual plane intakes. It is amazing what you can do to those two parts that will allow 450-500hp out of the package.
While you can easily swap out the iron heads for new aluminum, it is fun to see just how much you can get those old heads and intakes to flow.
Quite true, a couple hours' work with a die grinder and a a round-nose and acorn burr does wonders. I did the two heads and manifolds in about 2.5 hours, and they'll be able to feel the difference. And if you do it yourself, think of the bragging rights. Sounds so much better at cruise night than "I wrote a really big check".

Those old school guys were pretty smart. I knew one of them. That old Cobra Intake is within a few percent of the best manifolds available today. And they designed it with intuition and slide rules.
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