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Performance Enhancements for a 318

68Coronet500!

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I'm trying to beef up my 318 and looking to start with headers unless anyone has a better idea. I'm not looking to build a race car but would certainly like more power than the stock 318 in my Coronet and am looking for some suggestions.

I checked Jegs and they make an exhaust kit for a B Body that runs at 2.5 inches at the outflow and it's leveraging hooker headers. I also see that hooker makes another model with a 3 inch outflow, which do you think best fits what I'm trying to accomplish?

Once that is completed, what suggestions do you have for increasing the power while keeping it out of a shop for extended periods of time?
 
More cubic inches, seriously I had the same dilemma. Once I started the pricing of small block performance parts I discovered I can go big block for less money.
 
More cubic inches, seriously I had the same dilemma. Once I started the pricing of small block performance parts I discovered I can go big block for less money.
seems that everyone I talk to in Southern California wants a small fortune to do an engine replacement. the other issue is that it will take extended period of time for being in the shop and I'm not really into that either.
 
Cheap set of headers into dual exhaust, 4 barrel 600 cfm carb, Edelbrock Performer or similar intake manifold and a new camshaft. Maybe 3.55 rear end.
That should wake it up a fair bit. Do the heads further down the track if your not satisfied with the above.
 
Pros & Cons. I'm the kinda guy that says use what ya got.
Yes you can do allot with a 318 and it will run like a scared rabbit.
All it take is time and money. Intake, carb, headers and exhaust are a good start.
3'' exhaust is not a good idea with a small displacement engine. Not on a street car.You will kill performance.
Next is what gearing do you plan on using or what do you have? 3.23 is a good all around street car gearing.
From there the sky is the limit.
 
Pros & Cons. I'm the kinda guy that says use what ya got.
Yes you can do allot with a 318 and it will run like a scared rabbit.
All it take is time and money. Intake, carb, headers and exhaust are a good start.
3'' exhaust is not a good idea with a small displacement engine. Not on a street car.You will kill performance.
Next is what gearing do you plan on using or what do you have? 3.23 is a good all around street car gearing.
From there the sky is the limit.
Thanks Darter. Sounds like I'm on the right track if I'm not going full replacement.
 
seems that everyone I talk to in Southern California wants a small fortune to do an engine replacement. the other issue is that it will take extended period of time for being in the shop and I'm not really into that either.
Not really, since you already have a running car finding and building the engine you want as finances allow is also a choice. Your car will still be drivable while you build.
 
I’ve got a 78 318 in a 66 polara. It’s stock except for a mopar performance purple cam and some port matching to the heads. I’ve got a 360 4bbl intake on it with port matched stock iron heads. Aim running a thermoquad but I’ve run hollys and edlebrocks also. That little engine moves that 4200lb car very well. Put some timing in the 318. A good starting point is 12 degrees idle, 34 all in mechanical advance and 52 degrees all in vacuum. Car with 2.94 gears get 18 mpg at 70 mph all day long and is a force to be reconed with when it kicks into 2nd at 65mph. Don’t give up just cause you’ve got small cubes. Turn it faster... mine turns over 7500 rpm and really pulls... this is coming from a guy with a 500hp 440 also. Cam and valve springs... don’t over cam the little 318 and it will really wake up. Lots of timing and good valve springs. Tuning is key!
 
Appreciate the insights. I don't have the technical competency or equipment to handle it on my own but am meeting with a mechanic in a few weeks and will see how capable he is on the tuning front.
 
If you want instant seat of the pants feel as cheap as possible, install lower gears in the rear end. IMHO
 
Nobody seems to have mentioned the torque converter. Waking a engine up is a combination of intake, exhaust, cam, gearing, and TQ (in a auto).

Mark
 
Duals in 2.25 or 2.5"

Headers may be more pain than gain unless you get $700+ TTI, Dougs, or Hooker Super Comps.

Small 4 barrel and the aforementioned Performer intake.

Maybe a small modern, "RV" type cam like the comp 256 or Lunati equivalent.
 
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If it has 2.76 gears, one step to 2.94 or 2 steps to 3.23 will be noticeable but not require a converter change nor will the cam family listed above.

...add a sure grip while you're in there.
 
Gears are great, but you need to know how, or know someone who knows how to set them up correctly. The OP stated that he did not have technical knowledge or equip.

Mark
 
A 4 barrel and intake, a nice dual exhaust and a performance curve for your distributor will do some good. (@HALIFAXHOPS) The next step would be taking the engine apart, raising the compression, bigger cam, headers, and performance heads. To make that all work well you will need a higher stall torque converter and different rear gears. Speaking of gears, changing from a 2.76 to a 3.23 or 3.55 is a nice change in performance.
 
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The right curve in your distributor is a great improvement to start with.
 
Headers with 2 1/2 exhaust, a 4bbl with 600ish carb will do wonders. After that a gear change 3.23 or maybe 3.55 and then a good quality converter will amaze you.
 
Like I said, the sky is the limit !! More than anything have fun,You will learn allot here.
 
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