aproximate horse/torque
 

Ive yet to dyno to car but i know the original engines 289 2 barrel engines were approx 200 horsepower w/ approx 210 ft/lb of torque...but after i installed this 4 barrel edelbrock 600cfm and the rpm gap intake now i wonder how much torque/horsepower im getting now. It drives me nuts when people ask me at car shows how much horsepower/torque it has and i guess at 250ish for both...is that semi accurate...when kids ask at school i normally tell them some bogus number and just tell them i dont race idiots that cant drive while doing the speed limit so dont try matching me up.....but is 250 horse 250 ft/lb torque accurate...other mustang owners ask me when i take them to shows sometimes and i feel semi-dumb....like i said all stock except for the intake and carburetor.....( im just wondering about brake horsepower)

i would think it would make something more like 200/300 stock.......

I think you would be really pushing to get 150hp at the rear wheels. The figures by Ford were fudged a little and were at the crank I thought. You would lose a bit of that through the gear box and diff. The only real way to find out is put it on a dyno.

1. dont worry if you dont know. 99 percent of mustang owners never dyno their car. its not a big deal.

2. screw the kids at school. if the first question they ask you is how much horsepower it has, its because they have a small_________

3. your engine is basically stock. remember that if thats the original engine than its over 40 years old. so its gonna be worn out. and so probably worth less than 200 to start with. adding a carb and intake would probably only restore the car to normal horsepower levels.


4. figure a 15% loss in power through the drivetrain. normally people say 10-15 %, but this is an older car. and much less efficient putting HP on the ground. im normally overcautious.

5. if you have an auto trans yoru losing more horsepower than a manual.

id gamble and say 200-220 and 280-300 at the crank.

it may not sound like a lot. but its something to be proud of, remember your car weighs nothing compared to some of todays cars. and that 90's GTs were in the same ballpark

You were doing so well...right up until you gambled ;)

If the car had 200 rated HP stock that was at the crank with no accessories ;)
A 4 barrel intake and carb won't add 80-100 HP...in fact as I recall the 4 barrel version of the same motor was rated at 215 HP at the crank with no accessories.

Then you have to start subtracting HP loss for things like:
Water pump
Alternator
Power Steering
AC

To get a number comparable to a modern car HP rating since they changed they way you measure crank horsepower in the 73/4 date range so that manufactures would stop fudging the numbers so much (in a nut shell anyway).

oppsss i meant 200-220 HP* at the crank and 280-300****** TQ***. sorry i wasnt meaning brake. i see thats what he was asking.

like i said its an old motor. and ratings would vary. idk the condition of the motor, if it was ever rebuilt. or what kind of accessories hes running. for all i know that motor could have been rebuilt last year. and have very efficient accesories. or none. idk.

either way, id believe hed be running close to whatever the stock numbers would be. not enough difference to notice it driving. i think we can all agree with that.

if you added an intake and carb and nothing else you may pick up about 20hp if you have headers then it can be about 30hp.

this isnt the orginal engine and i bought the car done and ive only torn it down to the heads and never saw the crank or cam....it has no stamp on it so im assuming its a crate motor but my guess is that it is nearly the same as the original engine because i bought the car from a guy that was in his mid 70s and he said nothing of any engine mods he had done and never really even talked much about it when we asked...i was just wondering brake horsepower and that helped alot thanks guys!....and the torque was messed up in the first place i meant 310 not 210 :p

Realistically, I'd say 180hp, plus or minus. Like dodgestang said, that 200hp for the C code was at the crank with no accessories, no exhaust, and optimal test conditions. The increased power for the A code was partially due to a higher compression. Tack on exhaust, accessories, and an aged engine, add the better carb and intake, and you're probably right back where you started.

A guy on another forum dynoed his 67 fastback with 289 w/4bbl carb and he only got 130hp to the wheels.

Yup. Like Dodgestang and Starfury said, fudged power ratings. Not only were they rated without accessories of any kind, but they were often rated at gross horsepower and torque, which also excludedthe power lost to internal friction from bearings, rings and pistons. Since the friction rating was a purely theoretical calculation they could fudge it quite a bit. The gross ratings were supposedly the theoretical power ratings in the combustion chamber, excluding inefficiency from rod/crank angles. That's why engines like the Chrysler 426 Hemi were rated at 425hp one year, and then the EXACT same engine was rated at 375 the next. 50hp alone was lost just to friction and accessories. And even then those ratings weren't that controlled. The new(within the last few years) SAE net requires a VERY rigorous and controlled testing environment(it 100% eliminates the manufacturer's ability to fudge the power rating in any way), that's why a modern net rated car with 300hp(the 05+ Mustang GT's for instance) with 3,500lbs are considerably faster that older 400hp rated cars with 3,000lbs. It would depend on the manufacturer, the year and the vehicle. Often they'd under rate the performance cars to keep insurance down, and over rate the regular cars to sell them more easily.

That said, a stock K code with 271hp, was more likely about 220-240 true net hp, an A code 225hp was realistically more like 180-200 on a good day, and a C rated 200 was around 150-180. These are approximations though, since there are very few truly original Mustangs left with few enough miles to test them to know for certain.

Look at what BA said too, a 4bbl 289 was dyno'd by an owner at 130rwhp. When you consider heavy oiled inefficient transmissions of the day, and account for approximate power loss, that's only around 160-170hp at the crank.

Realistically a stock 289 with intake and carb is looking at maybe 180-200 at the crank, and like 150 at the wheels(on a good day)....so basically similar power as a lot of modern 4 cylinder "performance" engines.

The sad but true truth of our old V8 mustangs. Keep it on the DL dont want the tuner crowd to find out lol:p

Yeah, but the stock 351W Mustangs were some of the fastest, I think even back then they managed to get a few to run high 13's...on the crap tires of the day. But most 289's were pretty weak.