not another cam question!!

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duster731

duster731

young gun
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I was wondering if you all can help me pick a good cam for my build.


My build consist of
76 360 40 over all stock internals, zero deck
587 j heads slight bowl blend port job 188 int valve
Edel ld340 intake
Headers
273 adjustable rockers
Holley 750 dp
Msd 6al, msd ignition control box
150 spray of juice
4speed trans
3.91 gears

My goal..
Basically a drag race car that's streetable, cruise the streets every so often but run good at the track .. not my dd


I am just stomped on cam selection I know I want a solid flat tapped and something around a 106-108 lc I would also need lifters, pushrods, springs locks retainers as well


Any input would be greatly appreciated. Thanks
 
Nitrous engines like wider LSA's than what you have planned. You say stock internals and zero deck height. What pistons? Stock? So you had the block decked like .100"?

At any rate, I would go with something in the 250* @ .050 range with .550 lift and a 112 LSA. Providing you have the static compression to support it.
 
I'd call one of the good cam grinders and have a custom cam ground. Many times custom grinds cost nearly the same as an off the shelf cam nowadays. I've used Racer Brown with great results. There are other great companies out there too. I put a custom ground Bullet cam in a 418 for a buddy and it runs fantastic.

Also you might consider going easier with the juice since you say it's all stock internals. If the tune is right on it's not quite as bad but if your off much it plays havoc on things and 150 shot on a stock engine is a pretty hefty hit
 
the cam in mine...comp 269MM 239 247@50 549 560 lift 108 ....sounds wicked pulls hard ....
 
Wait! Stock internal, zero decked? Am I to understand that you have the stock piston inside there and the block has been milled to meet the slugs top?
Or did you replace the pistons? (With what brand/part number please)
 
Ok well its not zero decked at the moment but was going to get it done this week. Stock pistons, new rings new bearings...

The nitrous is non adjustable or I would start off with a 100 shot (nos powershot is the kit)

Any input on herbert cams? I ran one in my 318 sounded great and looked good when I pulled it out of the block.
 
You will have a major clearance problem with stock slugs. Notice the HP pistons have valve reliefs in them for clearance with highest cams.

Once this is sorted out, then we can go from there.
 
I doubt you will be able to deck that block enough to get zero deck with stock pistons without running into major problems. As rumblefish stated, you will have piston to valve clearance problems, not to mention intake fitment problems from cutting the block that much.

You need to replace the pistons with forged pistons with large valve reliefs to get it close to zero deck, then deck the block to make it exactly zero deck. Then you can start thinking about the cam.

Stock pistons and a 150 shot is a recipe for disaster. You're basically building a large grenade with the pin already pulled.
 
What pistons would be recommended at a reasonable cost and would I need to to do anyrhing to the rods or crank ?
 
In the heading it says 114 and in the description it says 106. Strange.
 
Most probably a typo. Found that,in my last Herbert catalog. They do offer different lobe center versions, of the same basic grind.
 
Yeah I called and theyvdo offer different lobe cebter grinds. .

But he also explained to me two options..

While running nitrous I can get a cam with a wider lc of 112-114 and have the car run great when I'm only using the nitrous whic wouldbt be all the time

Or

Get a 106-108 and have the engine run great and hard all the time but when I use nitrous ill get 110 or so out of the 150 shot..
 
The 114 pros:more street able,better gas mileage around town.cons:smoother idle,less mid range torque. 108 pros:"tough sounding",more mid range torque(2500-4500),.Cons:lower mpg,and drivability,less response on spray.731,custom cam grind would help. Think a 112,111 l.c ,230 int,[email protected] ,.480-.500 lift,minus lash.My..02....
 
Decisions decisions lol..

Honestly I'm liking a 108 lc or similar to the fact that it'll sound mean and run hard all the time.. so basically I should stay around 250@50 dur and 550 or so lift ?


Btw thanks for all of the input so far
 
I like the 250@, duration. The lift ,needs to be considered. Valve guide/retainer clearance,.050" minimum. A solid,requires a more aggressive spring. 120-140 ,on the seat,300-340,on the nose.Might need,to raise installed heighth,and mill the valvespring step on the heads. Here's a question: How mutch porting,was actually done?
 
Just a mild clean up kinda port job. Nothing major at all. Herbert recomended me the first cam I list along with dual springs that are good for 675 lift .. the whole kit including springs locks retainers lifters and cam would be $316
 
That is a lot of cam,for a 318.That dual plane,masks some h.p.,for drivability. In southern tongue"gonna be a ruff mutha,to tune".
 
No way in hell is 250@ .050 gonna sound tame even with a 114 LSA. I was thinkin more along the lines of a 112, though. It's gonna "sound mean" regardless.

Most anytime someone wants to build an engine to "sound mean" I just tune them out. Build the sumbitch to RUN MEAN and it's gonna sound like it. There's no taming a true HP engine. Even a stock 340 sounds mean.
 
RustyRatRod said:
No way in hell is 250@ .050 gonna sound tame even with a 114 LSA. I was thinkin more along the lines of a 112, though. It's gonna "sound mean" regardless.

Most anytime someone wants to build an engine to "sound mean" I just tune them out. Build the sumbitch to RUN MEAN and it's gonna sound like it. There's no taming a true HP engine. Even a stock 340 sounds mean.
Click to expand...

True it will sound mean if you build it mean. But it will sound meaner (or lopier if you want to define that as "mean") at idle with a lower LSA that he is wanting.

Lower LSA = Narrower power band
Higher LSA = Wider power band

All depends on what you want I guess. Seems like most guys who have N/A drag cars go for the tighter LSA than the wider. Just saying.
 
Remember what we talked about and the raised area of your current dished pistons. That's going to be the interference point for the valves on any long duration, higher lift camshaft.
 
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