stock comp. 318, which purple shaft is best?

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rabius75

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my 318 is still stock. im working on getting a 4bbl intake manifold from the guy at the junkyard.. trying to talk him down on the price since he got his jollies from FCKING me on my buick. he wants like, $125 for it. but im gonna get that **** from him for $75-$80. im going to get a set of headers and a 4bbl intake manifold/carb set up soon.
i had planned on gathering all my parts for it together first, then putting them in, since i will have the intake manifold off to put the cam/lifters in anyway, ill wait till i have the manifold and carb, and the headers... well. i can wait to put those on :)
now, im looking over the purple shaft cams, because i cant find the comp cam i wanted, which was a 266H (nobody has that specific grind for some reason), but im not sure which one is best for me. im gonna go with an RV/towing type cam, but i want the best one i can grab for 8.4:1 comp.

i figure its one of these two.

312-P4452761
Adv. Duration: .268°/272°
Dur. @ .050'': 228°/231°
Lift: .450''/.455''
Centerline: 110°
Basic RPM: 1500-5800 RPM

312-P4452759
Adv. Duration: .260°/268°
Dur. @ .050'': 221°/228°
Lift: .430''/.450''
Centerline: 110°
Basic RPM: 1200-5200 RPM

i want lots of low end since its a driver.. and i want to be able to light them up easily ;) but i want it to have a nice cruising speed, not too low in the rpms. im not exactly sure if i COULD use the 268/272 in my car with stock comp...

feedback is greatly appreciated :)
 
I put in the second one u got there,its a great cam people told me to get that one cuz u cant go over bored with the stock comp.i still havnt ran the car :roll: but i know that shes gonna do great,im pretty sure thats about as big as u can get for your car! :afro: MIKE
 
Make sure you get an intake for the 318 and not the 340/360. The ports on the 318 are smaller so you need to get the intake to match.
 
My advice... if your engine has close to or more than 100k, forget a cam swap. You would just be wasting your time and money. There is a lot more to it than just a cam and lifters. You would probably need new valve springs and of course a timing chain, plus all the gaskets required. Then as soon as you get it all running good, you spin a bearing. Or maybe your rings can't handle the higher cylinder pressure. Who knows? Just wait 'till you have enough saved up to rebuild the whole engine the way you want it.

Now you CAN go ahead with the 4bbl intake, carb and headers. My Dart has a 318 with 140k miles on it. I picked up an Edelbrock SP2P manifold for $40 on eBay and stuck a 500cfm Carter carb I had layin' around on it. Then I put Doug's headers and dual turbo mufflers. It sounds mean, and it will roast the right rear tire. I can just imagime what it would do with a higher stall converter and 3.55 gears and a sure grip in the rear end. No it's not terribly fast, but it does pull pretty good on the low end!

So save your cam money, or put it into gears and a converter. You might also consider an electric water pump and fan setup. That would free up 20-25 horsepower. Or how about just putting 1.6:1 ratio rocker arms. Point is, there are LOTS of things you can do to get more performance out of your 318 WITHOUT tearing into the motor.
 
I would call COMPCAMS up directly. If they don't have that cam in stock than they will grind it for you. If you go with the MP cams I would go the 260/268 the other one I would think would be to big for a mild build up. I have run the 260/268 in mildly built 360 and was very pleased with that cam. But like Gotdart said if the heads need to be redone or if the rings are going bad nothing is going to help that motor. Also definately replace that timing gears and chain set, that is allways the first thing I do when I get a Dodge engine. The stock ones are crap!
 
Greg made a good point. Thats a lot of work for a high mileage engine. I got my 82 5th Ave to run 14.9 with the stock cam in the 318. I put a Edelbrock LD4B, Holley 600 vacuum, MSD 6A, TA valvebody, 2000 stall, and a 8 3/4 with 3.91 SG. Stock exhaust manifold with 2 1/2" pipes and flowmasters. It surprised the hell out of me when it ran that fast, it was a pretty heavy car. I think the gears are what really helped.
 
headers and intake manifold and carb then eh? thats cool. that would have probably be what i did to it anyway. once i get my funds in order i had planned on re-ringing the motor and putting all new bearings in it, with new valve springs too. not a complete overhaul, but replacing all the most stressed bits... comments?
 
That sounds like a better plan. Save the cam change for when you redo the engine. Intake, exhaust, and ignition should wake that 318 up. At least you'll be able to reuse those parts when you redo your engine.
 
just my 2 ents, stay away from that junk yard across the street that guy gets you every time. Or at least look on ebay or a a used parts company fiirst, you are paying way to m uch for his junk. He sees you coming. What an ***.
 
im gonna go up there and have my deal worked out first. im not sure what kind of intake manifold it is, but if its a cast iron one, im gonna tell him ill give him like $60 (on the top side, i wont start there) and if he wants to get all bitchy, ill tell him, its a fscking cast iron manifold, it doesnt matter if its the only one you have, its not worth THAT much. if i dont get it becuase he likes to be a greedy *****, then ill just stay after him for a while (as im saving money for a NEW one), if i still dont get it, oh well. i can get a new one.

would an orange box (@ 6000rpm rev limiter) be a good addition to my car? i was going to get one and a new distributor later on, and try to get me a HI 6... whats the best ignition setup for me if i cant spend TOO much money?

thanks, jeff
 
Quit worrying about an intake for now and just get your exhaust system done. You need this taken care of before any other mod will be beneficial. Ask me how I know... :lol:
 
Get your exhaust and ignition done then work your way up to the intake. A MSD will work fine with a stock electronic distributor. The MSD 6A is fairly cheap, it just doesn't have a rev limiter like the 6AL. But I don't think you need to worry about a rev limiter for a while. Let us know when you get the exhaust done, I'm going to be parting out a 73 Duster that has a LD4B on it. Thats the LD340 with 318 size ports and I don't run any 318's. The car has a 360 with 318 heads :scratch: I don't know what that guy was thinking. Anyway I'm not planning on using it.
 
hawaiiduster!!!
ol buddy!! :)
j/k
what do you want for that manifold? fair price, ill go with it, i wont be slapping it on right away anyhow, i dont have a carb. but i want to secure the parts so i can do it all at once.

i was going to go with the mopar performance orange box for my control unit.. you say an MSD box instead? what about a coil? should i get a more powerful one?
 
i got the MSD blaster coil its great but then again its just a coil,im gonna get me one of them MSD boxes soon to finish off my igni.i cleaned up my dist that hawaii sent me! :thumleft: i just need a box but im gonna run my points to get her running and driveing cuz they hav all new points and got it back from a rebuild,it worked once its gonna hav to work for a little longer :shaking:
 
get that **** running already. dont make me come out to cali and light a fire under dat ***! :)
 
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