Thanks Blainer
Plenty of info from the Fox, X-shell Panther and F100 owners who got these engines stock for a year or two.
I did a little research. Hope this helps identify the 4.2 engine option for those of us who don't want to be caught out by this engine. Its certainly a aberation that tricks a lot of people in the wrecking yard and ebay.
Use of non stock oval port gaskets on a stock intake and head 255/ 4.2 liter is an issue as the port mismatch is unfavourable, with air fuel mix slamming into an unsealed annular zone. Ever other Windsor V8 from 1962 to 2001 has square ports, not oval.
The first 1980 4.2 ran a RF EOSE-9425 casting intake, which were weird as bat poo, with windowed and high voids intake with all the alloy taken out. Even the carb base was stand alone stud and boss.
It got a revised part in mid 1981, but
homer302's 1982 intake should still be similar.
I've not seen a full set of "all angles" photos of the later intake yet, but it is still a swiss cheese high voids casting with very little aluminum. They saved around 65 pounds on the 255 engijne in total, going from 465 dressed without p/s and A/C, to 400 lbs,
most in the crank,
some in the heads,
a little in the intake,
a lot in the exhausts, and
more in the windowing of the bulkheads and downsized thinwall 3.68" bore of the block,
very much like what Pontiac did in the 1978 to 1981 301 engines
Here's a picture I unearthed
There was the mid 1981 swap to 50 Oz unbalance, and another manifold with the same gasket
NOS OEM Ford Intake Manifold Gasket E1SZ-9433-C 1981 Mercury 255 4.2
E1SZ 9433-C 255 V8 Water Passages and Ports
The other 5.0's are indeed square.
In fact, everything 302 from the first J code 4-BBL of 1968 C8ZE-9425-A to the last 1984 4-BBL RF E4 ZE 9425-GA, is all square. Same with 2-bbl intakes for all years. The 255 was the undisputed odd ball, smaller port wise then any 221-260-289 as well.
Its sole purpose was to add 1.5 miles per gallon of Highway fuel economy to the 1980 CAFE fuel figures compared to the 1979 5.0. It did it not just by capacity reduction from a 3.68" bore, but by reducing everything they economically could in the engine.
As for the Edelbrock SP2P 289 4bbl intake #3355 used by Car and Driver in the 160 hp 132 mph project Capri, it
was common, but you'll only find 2-bbl 289 versions on ebay.
I got one listing long ago on the 4v 3355, but its no longer there
A 4V HO intake would fit if the porting was reworked, either at the heads, or in the intake by Devocn/JB Weld or Tig welding the curves at the gasket face.
Here's the reasonably common Edelbrock SP2P 289 2bbl version.
That intake came out well before the 255, and it lookes like Edelbrock used the same reduced stud and throttle shaft casting method that Ford and AMC used with some of the early 4350 series Autolite 4-bbls to mount the carb.
Connect With Us