360 j heads,318 build up?cam?

mopartruck63 · Post by **mopartruck63** » Tue Feb 07, 2006 7:35 pm

have a 1972 stock 318,have set of 1972 360 j heads want a bigger cam for it ,not sure what lift the springs handle,its going into a 63 sept,no racer,have a 4 barrel stock 360 intake not sure of converter ill need depends on cam, just want a bigger cam for the change,and more power like ,need to know how much to shave the heads to get decent compression.not building a a drag racer,mainy want to know how much lift the springs in my heads will handle,how much to shave the heads like 8.5.1 or higher,maybe a little less.and what will change now that the heads are shorter,im really stressin this.

dodgetkboy78 · Post by **dodgetkboy78** » Tue Feb 07, 2006 9:55 pm

Stock springs seem to be good for about 450 lift, and 5000RPM. (from my experience)

The 915/587 casting 360 heads usually CC about 68-72, unless you deck your block, the piston is usually about .030-.050 down, that gives you about 7.5-7.8 to one. (about) Including .040 for a gasket (you can get a .028 gasket).
Milling .040 off of the heads, should get you around a half of a point or so on average. Should bring you around 8-1.
If, you get the block milled, and the heads milled, or, get you some cool high top pistons, you can easilly get it to 9-1+.
(I would get some pistons, and not mill anything)Also don't forget to buy a plate and a burret, and cc your heads, or you will never know exactly what compression you have.
If you mill the heads, you will need to mill the intake a little, and get shorter pushrods, not a big deal.
Don't stress about it, the cop car 318's had 360 heads slapped on, and a 240/248 cam, anr ran awsome. If you keep the cam under 260/260 adv, you wont need to mill a thing, and have a good strong truck motor.
(PS, on a mild street 318, your stock 675 casting heads, with a little bit of bowl work, and 1.88/1.60 valves installed, will outperform the big port 360 heads)
Don't stress, it ain't nothing!

mopartruck63 · Post by **mopartruck63** » Wed Feb 08, 2006 2:59 pm

isnt bowl porting grinding and polishing the material around the guide and valve? thinking about doing the stock 318 heads up,i just need to know which cam,and springs to get now.and what intake,4 barrel 318 one,i have a 360 one but im not gonna go that route.

67LB318 · Post by **67LB318** » Wed Feb 08, 2006 3:32 pm

Yep.....That's what bowl blending is. The iron Thermoquad intake is pretty good for a stock piece. It should work pretty well for what you want.

As far as a cam recomendation goes.....Personaly I like CompCams. A lot of people like the new Lunati VooDoo. And a lot of people like the MPP Purple shaft cams too. And they all work great

As far as a recomendation goes I'd look for something similar to this

CCA-20-220-3 Comp Cams Extreme Energy Hyd. Flat Tappet. RPM Range 800-4,800 RPM. Duration at 050 - 206 int./212 exh. Valve lift with stock rockers. 0.432 int./0.444 exh. lift

But that's just my opinion.

That's a summitracing part number by the way.

dodgetkboy78 · Post by **dodgetkboy78** » Wed Feb 08, 2006 3:53 pm

mopartruck63 wrote:isnt bowl porting grinding and polishing the material around the guide and valve? thinking about doing the stock 318 heads up,i just need to know which cam,and springs to get now.and what intake,4 barrel 318 one,i have a 360 one but im not gonna go that route.

I like Comp cams, and have good luck with the 260/260, and the 268/268 in trucks.
You got it! Wouldnt polish though.
Go tp COMP cams, and look at they're website, they have cam, lifters, and springs that come matched in a kit.

The 360, and most 318 4bbl intakes are big port, a weiand action plus would be a better choice, for it is a small port manifold.