I'm planning to purchase a remanufactured OEM spec 300/4.9 inline six from Power Pro 2000 and would like to know which year had the highest compression ratio for the carburated engines. I'm planning to install an ISKY 262-supercam, an Offenhauser C Series intake topped with a C&S specialties 390 Balanced Flow 4 barrel carburator and header. I would also like to know which automatic transmission will best work with this engine. I'm planning to replace a 200 SD inline six and two-speed automatic in my 1956 S-100 IHC.

Thanks in advance for any help you can give me.

 

The greatest truck engine ever made.

Specifications

Bore & Stroke: 4.00" x 3.98"
Compression Ratio: 8.0-8.9:1

1965-1972
Brake Horsepower: 170 @ 3800 rpm
Torque: 283 lbs.-ft. @ 1600 rpm

1973-1974
Net Horsepower: 101 @ 3000 rpm
Net Torque: 223 lbs.-ft. @ 1600rpm

1975-1977
Some were the same as '73-'74 others
were bumped up to 120nhp @ 3400 rpm
with the same torque specification.

1978-1986
Horsepower ratings varied from 101nhp, 115nhp, 117nhp
and 120nhp @ 3000-3400rpm. Torque ratings remained
223 lbs.-ft. @ 1600 rpm.

1987 - 1993
Switched from carbureted to electronic fuel injection.
Compression ratio was 8.8:1
Brake Horsepower: 145 @ 3400 rpm
Torque: 265 lbs.-ft. @ 2000 rpm

1994-1996
Brake Horsepower: 150 @ 3400 rpm
Torque: 260 lbs.-ft. @ 2000 rpm

Perfomance Modifications

Carbureted

Air Intake: Most people seem to like K&N's, but any filter open
360* is an improvement over stock.

carburetors: A Holley 390cfm 4bbl is the most popular choice and
works best especially with stock cam, a lot of people are happy with
500cfm Edelbrocks too though. Only use a 4bbl with an Offenhasuer
or Clifford 4bbl intake, use a 2bbl with an adaptor plate.

Intakes: Both Offenhauser and Clifford make a 4bbl intake for the 300.
Offenhauser seems to be the favorite because it's cheaper and just as good.
Clifford makes 2 and 3 carb intakes also.

Headers: Headman and Clifford are both good choices, ofcourse Headman is
cheaper.

Camshafts: Both Clifford and Isky make a wide range of camshafts.

Ignition: Any performance ingition, MSD is most popular.

Heads: You can have porting, polishing, bigger valves also putting on a
240 head will raise compression.

exhaust: High flow mufflers, dual cats, no cats, hollowing out cats.
2 1/4" True duals with split headers is suppose to work the best.

Electronic Fuel Injection

Same kind of stuff except instead of slapping on a bigger carb, since fuel
injection doesn't use one, duh, you'll want bigger injectors and maybe you can
find a bigger throttle body that will fit.

Turbos: Some people have had custom manifolds made and used turbos of
Chevy deisils, there are no kits for this so it would be a custom job.

Chips: To my knowledge there are no performance chips for the 300.

Common Problems

Ford's 300 inline 6 is a fairly problem free engine for 200,000 to 300,000
miles if properly maintained. Common problems with the carbed models
are vacuum leaks, just little ones can cause hesistation, rough idle, etc.
The stock Carter 1bbl carb seems to like rebuilds too. On the automatic
transmission models some people have problems with overheating, this can
be fixed with a cross-flow radiator and flex fan or a electronic fan. Besides
that if their over reved the 300 is known to throw rods or have early valve train failure.

As found on the Net @ http://www.clubfte.com/users/fordflaresides/300.html

Cheers
Colonel Flashman
Red '58 M-100
Blue '58 M-100 Panel

 

If you can get a C6 in there, do it, its a verry fine tranny. C4 would work, but C6 is better.

And I would say 83-84-85 Y block is what I would choose. Says in the chiltons manual I have here that they are all the same compression ratio from 76-86, wich I don't think is true The 83 has the stud mounted rockers, not sure about the 84 or 85... never had one of them open, although, I own a 84, and dad has an 85, and I have an 83 rebuilt that I am assembling.

CR is about 8.4:1 on the 83, and probably the same for 84 85