Thread: How much cam lift can it handle?

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I am building a 68 327 60 over. I have KB157 pistons, here is the link to the specs of them http://kb-silvolite.com/performance....etails&P_id=45

The cam i want to use is a comp magnum hydraulic roller and i either want the cam with .560lift 289 dur or 600 lift 314 dur. just dont want the pistons to smack the valves ya know? im using a single plane vic jr, and a custom built carb from pro systems. Some iron eagle heads are also topping it off. 64cc, 202/160 valves, and 200 runners. im working on getting 500 plus hp. It doesnt have a body yet but it will have 410 gears and a 3500 stall.
Thank you all,
Mike.

Originally posted by Arrythmic_mike
I am building a 68 327 60 over. I have KB157 pistons, here is the link to the specs of them http://kb-silvolite.com/performance....etails&P_id=45

The cam i want to use is a comp magnum hydraulic roller and i either want the cam with .560lift 289 dur or 600 lift 314 dur. just dont want the pistons to smack the valves ya know? im using a single plane vic jr, and a custom built carb from pro systems. Some iron eagle heads are also topping it off. 64cc, 202/160 valves, and 200 runners. im working on getting 500 plus hp. It doesnt have a body yet but it will have 410 gears and a 3500 stall.
Thank you all,
Mike.

Anytime you call technical at any cam company, they want to know what kind of car, how much weight ,intended use,as well as trans,gear,and converter, etc.
Educate me, If you dont know what your're going to put the motor in ,or how much it's going to weight, how can you effectively select a camshaft ?
You might enjoy reading, Danger mouse ,Dec 2004,Super Chevy magazine.That series went on for about 18 months and it may change your thinking,especially on the heads.
Good luck, Have fun!

You need to check your piston to valve clearance with that much lift and duration. I'm running a 266/270 duration at .050 with .640 and .646 lift solid roller. I have extra deep valve reliefs cut into my pistons, don't remember how deep. I'm .014 in the hole on my pistons with .030 head gaskets. I have .1 on the intake valves and .15 on the exhaust. I think the recommended min on intake is .080 and exhaust is .100.
Best think to do is check it out or you just might be putting hole in a piston with a valve.

That's one heck of a lot of cam for a 327. Going to have to rev the snot out of the thing to make good horsepower, why so much??? Must be drag race only???

Originally posted by Dave Severson
That's one heck of a lot of cam for a 327. Going to have to rev the snot out of the thing to make good horsepower, why so much??? Must be drag race only???

My friend's dad bought a 1979 Malibu with a 40 over 327, his dad let him bring it to school and, I listened to it idle, it's got way too much cam in it, barely idles. I told him to tell his dad that I thought the cam was too much for the 327 and would be better with a milder cam, his dad told him to tell me, he arleady knew the cam was too hot, he's gonna replace it with somthing with less rump.

http://www.fordmuscle.com/fundamenta...ve/index.shtml

http://www.centuryperformance.com/piston2valve.asp

http://www.marphis.com/p-v_clearance.htm

http://www.rehermorrison.com/techTalk/41.htm

http://www.fordmuscle.com/archives/1...ov/index.shtml

Being realistic, a street engine can only handle so much cam before it begins to lose power. Larger cam does not = more horsepower. There are a lot of things to consider. Since you are putting a Comp Cams cam in it take the effort to check with their tech dept. and ask for their input.
As long as we are being realistic, think about this. Do you have any idea as to the likelyhood of a 327 single carbureted engine pulling 500 HP? There has been a lot of serious engine builders over the years that have been trying to do that unsuccessfully.
A fellow just the other day was looking at a car I am building. He said " My engine would look good in that car. It is a 383 stroker pulling over 600 HP". Turns out that it is a single carbureted engine also. It was all I could do to keep from telling him, "Bull S--t. I built an engine for this car that is a 383 stroker with fuel injection, siamese runners, full roller, and if it pulls over 430HP I will be greatly surprised.
With your engine bored .060 over you will be pushing about 333 CI at best. You would almost have to be pulling 1.5 HP per Cubic Inch and that aint gonna happen unless you are on an unlimited budget. If you can squeeze much more than 1.0 HP per CI you will be really lucky, or a much better engine builder than I am.
Techinspector will back me up on this I am sure. (Maybe)
Ed

Ed, thanks for the reality check

a 0.060" over 327 = 337 cid

it takes 1.6 cfm to make 1 hp

500 hp takes 800 cfm

It will require 8,200 rpm's to make 500 hp with a 337

Hi, Tech. It has been a while.
Ed

Hey Ed

Mike, you might want to take Tech and Ed's suggestions, they've both been around this hot rodding stuff for awhile and know well what works and what doesn't.

thanks for the replies everyone. Really appreciate it. So what would be a good hyd roller setup for it then? i want something with a good lumpy ide and good power through all bands. is just a standard hydraulic cam and flat tappet a better route to go?

It will be far cheaper. A good full roller setup will cost well in excess of $1000. A good flat tappet Hydrulic cam kit will be around $300 or less. Talk to the tech Dept at Comp Cams. They don't want their cams to look bad. They will recommend what it will handle.
ed

Originally posted by techinspector1


it takes 1.6 cfm to make 1 hp

techinspector1 -

Is that a calculation for that motor, or a general rule?

Thanks - Bert