I recently inherited my grandma's '65 Mustang (289, 2 barrel). She runs fairly well (sounds good, no rattling) but is really lacking power. I'm almost full throttle accelerating to normal traffic speeds. She also hesitates a ton when I hit the gas.

After doing some research I replaced both fuel filters (one on the carb and one in the fuel pump). I also replaced all of the spark plugs and plug wires. She maybe feels slightly better, but not much. If I'm at a stop sign and turn right onto a major street (speed limit 45) I have to really hit the gas for quite a while to get up to 45. And when I do hit it, she still hesitates a lot (both from stop and while moving).

I guess the next step would be to rebuild/replace the carb? Anyone have any other suggestions?

Thanks

 

How many on it, AT or MT

 

The engine code is C: 289 V2.
The transmission code is 6: C4-Auto (3 speed).

 

Sorry, forgot the mileage...
She has about 125k but hasn't seen a lot of use lately (last 15 years). I believe the engine was rebuilt once a long time ago (late 70s or early 80s).

The spark plugs I removed didn't look like they had much wear but 5 or 6 of them were black.

 

I'd rebuild the carb first. I did my first carb on my old 2 barrel a few years ago and it's really pretty simple. I found a website that had pictures and step by step instructions. I think the kit cost around $20 and I did it in one afternoon. Mine was stalling and sometimes dying from a dead stop when I hit the gas. After the rebuild I adjusted it with a vacuum gauge and it ran a ton better. Just be careful tightening everything back together. I developed an accelerator pump leak once mine was back together. I also have an old Autolite 2 barrel in the garage if you need spare parts.

 

check the timing, total and initial. also you may want to replace the points and be sure they are gapped correctly. check the condensor too, do a voltage test on your coil, for resistance as well.

if you going to keep the car and your willing to spend a little bit, get a petronix electronic ignition, its very easy to install. and get a coil to go with it too. may want to replace the dizzy cap for good measure.

its most likely points or timing is my guess.

you can find videos on all that stuff pretty easily

 

Remember, by today's standards a 289 2 barrel with a 3 speed automatic is going to be a sort of a slug. That's why the market is so great for upgrades. Run some fuel cleaner through it as it probably has a ton of varnish in the carb. Normal service on this vehicle would be filters, you did this, points, condenser, plugs and distributor cap. Just replace them, you will eventually anyway or go the electronic route as above. New wires, if the old ones are original. Use a timing light to check for mechanical advance to insure the distributor springs are there and work. Fuel pumps also are replaced due to the diaphragm and return spring.
Carb rebuild was a normal service item because the accel pump diaphragm usually got cracks and holes with age.
Have a shop change the transmission fluid and filter and check the diff for lubricant.

Your 0-60 time for this car running well would be a little under 10 seconds. Not a bolt of lightning.

 

What is the rear gear ratio?

 

Thanks guys for all of your replies. I wouldn't expect this car to be fast but I also wouldn't expect it to be slow. Compared to my super basic v6 Dodge Dakota, the Mustang is a slug. Heck, my wife's little Mitsubishi Lancer has them both beat (stupid 5-speed stick has some zip!)

As far as the carb rebuild goes, I'm also considering upgrading to a 4v. Unfortunately, due to the blackening of the spark plugs I removed, I worried that there may be some excessive engine wear as well. I may end up taking the car to a restoration shop, if I can get the wife to agree (doubtful).

 

Do a compression test. You can do all this stuff at home in little time. Just use your local auto parts store rent a tool program and Google. You'll be good to go.