Okay this is for you "Mopar Gurus" . Okay recently installed a 1986 LA 318 904 combo into my 55 Fargo truck. This was mated to Mopar 8 1/4 diff 3.23 gears open drive. Said engine has the cast"302" swirl CC heads too, but no roller lifters. All smog, lean burn removed, regular electronic ignition added as well as non lean burn Carter BBD carb. Smog ports on heads plugged too. 1974 318 exhaust manifolds and dual glasspacks, no cat obviously. Okay so said motor netted 145 hp outta factory. While no race engine, it sure feels like a lot more than 145 hp to the wheels. Yes my flathead 6 was sickly but this little combo scoots along quite nicely. Im gonna guess maybe 170 hp out of it?...lol
Well, a stock '68 Dodge 318 made 230 HP, so it's safe to assume it should be at least 195 in my opinion. Should be a sweet combination.
I think the 1968 used gross HP ratings and the 1986 net. I guess we all know that... In 95 I bought a 86 D150 with a 2-bbl LA 318 and TF. It was a good daily driver/work truck, but no speed demon. But, it sure felt like more than 145 hp.
A bump up of about one point in the compression, and probably a little cam advancing would get you where the HP of the 68 was. But it may already be pretty close, as I remember, about 72 or 73 Mopar (and the entire car industry) changed the way the came up with the HP numbers to appease the insurance industry. All motors, industry wide, had a drop in the HP numbers though the cars didn't seem much slower. Gene
Of course its night and day. But I daily drive a 400 hp Hemi in off topic vehicle Its got nice grunt not super revving but nice and torky...gotta watch on gravel as assend breaks out easy even at 50 mph.. I have had it up to 80 mph on highway not difficult with lot more to go. Prefer to keep truck 60 to 65 as per needing suspension work.
Horsepower does not tell the whole story. A mildly tuned, 318 with 2 barrel stock cam and single exhaust is going to run out of breath before it revs very high and therefore not score high HP which requires high RPM. But in the low and mid range speeds where you do most of your driving the torque curve will be fat and it will have plenty of punch. It would be quite possible to hop up that engine with headers, cam, intake, carburetor etc, double the HP and get an extra 30 MPH top speed and feel slower around town unless you drop it into a lower gear and rev the snot out of it. As it is right now it should run fine on the cheapest regular, get decent mileage, last forever, and be an ideal power plant for a working pickup truck.
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