Cam for a 68 318

68Coronet500!

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I'm looking to upgrade my 318 and currently have a performer intake, 4bbl carb, hooker headers & exhaust, and am looking for some guidance. I'm thinking the cam should be first priority and then possibly the gearing in the rear end as it is currently low and I want a lot more power out of it.

Any suggestions? Also, when I'm having that done, anything else I should be looking at?
 

streetmachine

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For that 318 I'd recommend a the Summit K6900 Camshaft Kit and Cloyes Timing Chain/Gears. For the rear axle ratio I would go with 3.23s or a 3.55 ratio.
 

451Mopar

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The stock 318 cam is pretty small, I think less than 200 duration @ 0.050"
You can cam it up a bit, like around 210 @ 0.050" and get by with the stock torque converter. You will want to re-curve the distributor also for more initial timing.
With more that the approx 210 @ 0.050" duration, the engine will respond much better with a high stall torque converter.
The Summit K6900 mentioned above would be a good inexpensive choice.
 

toolmanmike

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I'm looking to upgrade my 318 and currently have a performer intake, 4bbl carb, hooker headers & exhaust, and am looking for some guidance. I'm thinking the cam should be first priority and then possibly the gearing in the rear end as it is currently low and I want a lot more power out of it.

Any suggestions? Also, when I'm having that done, anything else I should be looking at?
You might find some good reading here: Search Results for Query: 318 cam | For A Bodies Only Mopar Forum
 

66Satellite47

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Back in the day, I built a 360 for my tow vehicle, '76 van. I used a Comp High Energy hydraulic. Worked really great. Good gas mileage and all the torque and power I wanted. Something similar would really help a 318.
 

66Satellite47

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68Coronet, your post didn't say what rear gear ratio you have. I hope it's a 3.23. The quickest improvement you could make is a quality 10" torque convertor. It will make a ton of difference, more than a cam change. Cam can follow.
 

streetmachine

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I'm going to assume here but, I believe your goal is just to have a nice cruiser correct? The other part of this equation is where you cruise will you be driving more city miles (aka stop and go, heavy traffic) or lot's of highway without much stopping?
 

Ron H

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After rebuild on my poly, headers, cam, solid lifters, ed, TC, among other things, I swapped to 3:55's having 3:23's. Wish I left that be. Cruising RPM is irritating at 65-70. Didn't find any more noticeable giddy-up off the line...granted, I have a possible issue with the timing currently running it full-mech; but runs like a top until such time I can dig into this.
 

toolmanmike

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There is no "magic camshaft" .
 

Darter6

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I did the Summit K6901 in a 68 273 Valiant that worked very well. Edelbrock Performer intake and 600 Edelbrock AFB.
Along with TTI shorty headers and their complete dual exhaust. Worked for me.
My 63 Belvedere has 1970 318 and I used the Comp Cams CRS 268H-10 Headers,duals,same Performer intake and 600 carb.
Sounds good, runs well for a stock bore,heads and pistons 318.
 

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