stock 318 more torque?

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cowboyroy

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Hi my names Chris i currently have a 73 Plymouth scamp its got 276 gears in the back. The engine is a stock 83 318 and i was wondering how i could get more torque.
 
Easiest way, More gear. 355s or 391s. From there, small headers and a good 2.25 or 2.5" exhaust.

Next easiest, swap in a 360. Nothing wrong with the 318 but the suffer from 3 problems, Poor heads, way small cam and low compression. Fixing those issue will make a huge difference but they arent cheap.
 
Pull the 318 and replace it with a 340! But gears would make a difference and would be a lot cheaper.
 
i have headers and a good exhaust with thrust mufflers. Right now i don't have the money for a 360 and i drive the car on the street everyday.
 
If you were to put a set of 355 gears in that car you would see a big improvement but it will also rev more on the highway. Also if you change gears you will need to change the gear in your tranny for the speedo or it will be way off.
 
Here's a decent little budget build: get some magnum heads, use whatever lifters and pushrods the guy who did it on the cheap (I forget, but I think he used AMC lifters and Mustang Cobra oil-thru pushrods), put a decent little cam in there, double roller chain, a set of headers and a good single plane. Some Mopar rag did it a while back, seems like the cheap easy way to go.

Gears help big time!
 
Do you know where i would be able to find a different rear end because right now i have the 7 1/4 i think
 
Put an ad on this site and you will be surprised how many responses you will get. Use the parts wanted section and I am sure you will find what you want. Good luck with your project! Also if you change your rear end you will have to change your drive shaft as well.
 
How much do you think a 340 or 360 would cost at a junkyard? because i have a junkyard that is fairy close with lots of old cars.
 
A 360 would be cheaper than a 340 if you can find one. Lots of 360's around so it should not be that expensive. Would be great if you could find a parts car that would have a motor and rearend. That would solve all your problems. Again there are lots of parts cars on this site and maybe even close to you.
 
Your probably not going to find a 340 in the junk yard but a 360 magnum motor from a pickup is more likely. I got mine for 250.
 
Cowboy, that 318 can wake up considerably if you make the decision to keep what you already have. If torque is what you want on the cheap, gears & a higher stall is the most budget friendly way.
 
What's your budget? If youve only got 500 bucks to play with, your pretty limited, but could do a set of gears if you can do them yourself.

I love stalland gear cars, even on small power they can be really quick and upset alot of horsepower junkies.
 
well i was just curious on what i should do the with motor if i should sell it or if i should get heads and a cam but i'm new to this stuff and am not sure what kind of heads and cam i should get
 
How wild do you want to get?

I had a 1974 plymouth valiant with a 318 that could pull a house off its foundation with all of the torque it had.

All I did was put in a new cam (Crane unit, I can try to find the part number if you want it), high rise dual-plane intake manifold from a 360 (higher ports, but it worked- I would advise NOT to go single-plane on stock heads/cam), a 600cfm eddy carb, and a single 3" exhaust. I kept the tranny and rear end stock (8-1/4" with 2.76:1 rear gear) and it was a fun little car. If I had headers and a dual exhaust like you have, I would have been plenty happy.

Tell us your main goal and we can be a lot more specific.

-Mike
 
I'd like to know what cam that was and will an aluminum intake make a big difference? I've got a 600 holley on it now. I want to try to make if fast and torque but still be alright driving on the highway.
 
Let's add this up:

What "is" the engine? Has the 4bbl manifold been added? Does it have stock heads? Was this a "cop car" 4bbl engine?

You say you have headers

What do you know about the cam, is it stock?

Offhand I'd say that if it's a stock 318 cam, adding the "modern equivalent" to the old 340 "stick" cam would wake that thing right up.

The second thing you MUST do is either recurve the distributor, or buy a performance aftermarket distributor with a short curve.

You want about 20-22 crank degrees "in the distributor", and run around 34--36 total (not counting vacuum, with at least 12 and maybe 15* initial.
 
Start with the rear and ditch the 7.25. Are you positive it's not a 8.25?Either way you go, you are gonna need a new rear....especially if you are considering building a 360.
 
i have a 340 cam in it and an iron intake 4 barrel. The heads are headman headers and the heads are stock 318 heads. I also am not sure how to re curve the distributor
 
So armed with a crowbar, we finally manage to pry some details out of ya LOL

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Sounds to me like you are about at the limits of a stock compression/ stock heads 318

You need to detail what you have for timing.

Start with a piston stop, which you can buy or make. Confirm that the timing marks are actually correct.

Then measure around your balancer, carefully, to get the circumference. Then either buy timing tape for that size, or use math to determine "how many degrees per inch" and mark off 40* on the balancer. Then you can use dividers to divide that in half for 20, half again for 10* marks, then add 10 at a time onto your 40 out to 60*.

Then divide those in half and you have marks every 5*. Make the 5* marks half as long, make the 10* marks all the way across. You can use a small square and a scribe, then a small file if need be. Mark the 10, 15, and 35 with paint so you can really see 'em

Then start with initial timing at some known point like 10* at the slowest idle, no vacuum, that you can muster.

Then rev the engine way up to see where it moves to. If you have two people and a tach, you can plot the curve versus RPM

You can gain or lose a LOT of low end throttle response and torque, and loss of high end with a poor curve, or a dist. with rusty advance mechanism.
 
curve the distributor and swap in some 355 gears. Those would be your next steps.
 
My dad and i already timed it we have a brand new distrubitor, spark plugs, coil, solenoid, and starter. Our distributor also does not have vacuum advance.
 
But what is the advance curve ? What is your initial, whats your total advance ? Just setting to the emissions sticker isnt the correct way to time for performance.
 
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