Well hello there. I have a 360 with the basic upgrades- its been rebuilt, along with new ignition type stuff, and then carb, intake, headers, exhaust. Nothing to fancy. Well, I have heard alot about cams. People keep talking about them, the Crane Cam in particular. I know a good bit about engines and all, although my skills I guess I could say went more towards the body of my truck. I was just wondering what the great advantages of installing this cam would be, and if there are any disadvantages? I am looking for more power overall, without upgrading to a new engine. A B&M shift kit is comming soon, but I am thinking about this cam and also, the install. Is the cam install easy-hard? Thanks!
Tristin

 

Tristin,

Can you tell me what kind of carb, intake, and compression ratio you're up to, as well as describing the exhaust system? And did you bore it over?

I can do a run through dyno2000 when I get home and give you some ideas of what you might be able to expect (can compare vs a stock cam replacement).

As far as the install goes, it can be a royal pain if the engine is in. If it's still on the stand, you're much better off. You can set the thing up so you're installing it straight down. You have to be careful of smacking any lobes around, and realise the bearings sometimes don't like to stay put while you're trying to get things in place. I had my machine shop install my cam -- felt safer that way.

John

 

Carter Carb 600cfm, Edelbrock 390 Alum. intake, 390 Hooker Comp. Headers, Flowmaster 40s, 2.5 pipes. Engine was bored .030 over when rebuilt- about 8k miles ago. The heads were built with hydraulic lifters also. Is a cam going to be worth it power wise? Or should I get a new set of heads, maybe some Edelbrock alum. RPMs? Thanks
Tristin

 

I can do you a few graphs on all those mods when I get home from work. Head flow is the greatest limiting factor on a naturally aspirated engine. You are only going to make as much power as the heads will allow you. However going with a slightly larger cam with a stock headed engine will still give it a wake up. Todays cams are much better than the older profiles. You don't really have to go much bigger to get a big boost in performance. The edel heads will sure wake the engine up also. Its all about how much you want to spend. The edel heads are still streetable enough to use a very mild cam with. I have all the specs for the stock heads, edel heads and any cam you are looking at for desktop dyno. Gonna need your compression ratio. Using an aluminum head with stock (around 8:1) compression is not a good idea. They dissapate the heat too fast.

 

Ok, this is making an assumption on your compression ratio. And I can't do graphs, RS can get those for ya

Keep in mind the dyno software doesn't count brands or anything like that, and I don't have flow profiles for your heads or intake.

Stock heads, 600cfm carb, dual plane intake manifold, 8:1 CR, Large tube headers w/ mufflers:

peak HP comes out to about 255@4000
peak torque 387ft/lbs@2000 and it just goes down from there.

With the crane 343901

hp: 279@4500 (273@4000)
torque: 373@3000 - peak
So you can see a few more horses but loose some torque there. Now if we bump that CR up to say 9.5:1 it looks a lot better:

stock cam:
hp: 280@4000
torque: 413@2000

With the crane 343901
hp: 307@4500
torque: 400@3000

Now that's with stock heads. no porting. Get a good porting job and have the CJ sized valves installed and you end up with:

stock cam 8:1
hp:316@5000
torque: 389@2000
9.5:1
hp:346@5000
torque:419@3500

Crane: 8:1
hp: 350@5000 (349@4500)
torque: 392@4000
9.5:1
hp: 384@5500 (355@4500, 378@5000)
torque: 420@4000


Thus you see compression ratio will make a huge difference. In the 390 you don't see the crane 343901 take away from the torque quite as much, and gives a better hp gain to boot. But the 360 is no slouch with good heads and decent compression.

Ratsmoker, give him some graphs?

John

 

John when I get a chance I will send you some flow files for the edel heads and the stock C8AE-H heads. I will also send you the cam spec file for the stock truck 360/390 cam. It will be a while before I can post a graph.

 

Here it is. This was done with a 600 cfm carb, 8:1 compression, headers, mufflers. The stock heads are C8AE-H. This is as accurate as desktop dyno gets for this purpose. I only posted the torque curves to eliminate some confusion. Torque is the only important thing as horsepower is just a fancy way to measure it. The only difference between these engines are the cam and heads. Everything else is the same.

 

Thank you guys for the info and graphs. I think I am going to go for a mild cam upgrade and see what type of change I notice. If I still want some more power, I'll add the Edel. heads. I think this combo would spruce up my lil 360- not nearly as well as my former 390 (R.I.P) BUT it will have to do for now. Thanks again
Tristin