Worth upgrading Duster 318 motor for more power?
 

Hello,


I was originally looking for a Duster 340 all original. Not so easy to find without spending too much money. Locally I came upon a 1973 Plymouth Duster 318. All original with 65,000 original miles on it. Rebuilt motor and tranny because it was in a barn since 1978. Car runs good, looks great. I was wondering if by adding a four barrell if it would add any power? Local guy / classic car shop told me that since this 318 engine is the low compression type he would have to do a lot to it to get good power, say $6000.00. Seems crazy. Would four barrel add hp andt torque to this car, and how much? I want car to be faster, especially 0-60 times.

Price sounds about rite now days... :) A lot depends on your budget !!!!
https://www.motortrend.com/how-to/cc...-engine-build/

M -

There's actually a lot you can do with that motor, but like Bob said, gonna depend on how much you want to spend.
Typical upgrades:
Cam, intake carb, headers + full exhaust.
Next step heads and differential gears.

That's what I did with my 74 318 decades a go, but added earlier 340 heads for the bigger valves and did a little machine work to help compression.
Pretty snappy motor.

BUT at $6000, you might want to start pricing out 360 crate motors and doing a swap.

Archer.

I'm old school, I learned years ago there no substitute for cubic inches, Build a 360....

I agree with what others have already said. For the money it would cost to get a little more from that smog 318, you could swap in a 360. You don't even have to buy a new crate motor, find a 360 running and swap it. Much cheaper and you can't replace displacement (cheaply).