I just installed and degreed my cam im my 446 street motor and installed it 'straight up'. Before I button it up I thought I would check here and make sure 'straight up' is what I need for my combo. The motor is a 440/.030 with Diamond flat top pistons and 440 source i-beam rods. The pistons are at ZERO deck and the heads are 440 source aluminum 'stealth' units with 84cc's and a port clean up and some bowl blend work. With a .045 head gasket this gives me exactly 10.0 to 1 CR. The valve spring pressures are 145lbs on seat and 375lbs open. The intake is a sixpack with Promax prepped carbs and the exhaust is HP manifolds with 2.5 pipes all the way back. The cam is a Compcams part# 23-710-9 which is their starting level retro-hydraulic roller. The cam specs are: lift .538int/.534ex, duration is .224int/.230ex @.050 with a 110' lobe seperation and a 106' centerline. The advertised power band for the cam is 1,800 to 5,800 rpm. The car is my sig 70 Challenger vert with a Tremec 5 spd and a Dana w/3.54 gears. My goal is street/cruising drivability. Is staight up ok or should I advance it a bit? BTW the cam came in at exactly 106' on the install. Thanks.

installed centerline is 106, which is 4 degrees advanced. if you installed it straight up, it would be at 110 i/c, 4 degrees retarded. you would not be happy. it needs to be at 106.

Where ever you decide to run it if you use a chain put it 1 degree advanced from where you want it and the chain will stretch out about a degree after some running

if you're at 106, you're good. like dthemi said, 105 or 105.5 would be good if you have chain drive. i usually go 1/2 degree (105.5)."straight up" on that cam would be 110, whatever the lsa is. if you installed 114 lsa cam at 114, that would be "straight up".

Comp grinds 4* advance into alot of thier cams. Your cam with the gears 0,s lined up measuring a 106 intake centerline is indeed 4* advanced.

If the cam wasnt ground advanced and your timing gears 0,s lined up with a 110 intake cemterline would be Straight up.

The term Straight can be confusing. Its more then just lining up the dots or the 0,s of the gears.

Its the cam being installed dead center between the intake and exhaust lobes at the pistons TDC between the exhaust and intake stroke. With a 110 lobe sep cam In cam degrees if centered at the pistons TDC it will be 55* away from exhaust lobe peak and 55* away from intake lobe peak. So this cam would be centered and considered Straight up by All the cam manufactures.

And because the crank turns double of the cam, 55 cam* equals 110 crank* So a 110 LS cam will centerline if Centered at 110 crank ATDC Putting it at 106* intake centerline would be 4* advanced.

If none of the above makes sence dont worry about it. You are indeed 4* advanced now at 106* mike

OK, I think I got it. Makes sense because the advertised lobe seperation is 110'. I'm going to leave it right where it's at. It will have plenty of . Heck, this motor will have about 75 hp more than the one that's in it now and I can't hardly keep it on the ground as it is.

75 more? perfect!

106 is perfect for that engine. Let her rip..

If the cam has been installed 'straight up' then the ICL is sitting @ 110*.

I always degree a cam @ 0.50 lift open/close , this is the figure to work too , the ICL is just the end result.

Let us know you're findings.

It seems to me that the last time I did this I used the .050 before/after max lift also. This time the instructions I was using recommended .010. As far as my saying I installed the cam 'straight up' perhaps my terminology leaves a bit to be desired. What I should have said was something like zero to zero, in other words I just lined up the marks, checked the degree wheel and got a value of 106'.

Class of chally you stated it somewhat okay IMO. Lots of people refer to straight up as lining up the dots. Even though its not absolutly correct.


In requards to 602 he is refering to another method of degreeing the cam. Not .050 from both sides of the intakes lobe max peak, but opening and closing crank degrees at .050 tappet lift.

I feel both ways work just fine. I myself prefer the peak lobe ICL. But I actually will view all 3 numbers. The opening lobe crank* at .050, the peak ICL and the closing crank* at 050 on the intake lobe.


As an example I will use your cam with its 224* duration @ .050 If at its intake lobe peak its at 106* ATDC With a 224* duration that means there is 112* of duration above .050 before and after that 106* Intake centerline point.

So to find the intake opening point at .050 subtract 106* of ATDC away to get you to TDC from 112* That leaves 6* left that will be BTDC Do the same kind of math for the closing at .050 after 106 CL and you get 74* to BDC + 38* ABDC to =112*

So your cam with 224* duration @ .050 installed at a 106 ICL will have the following timing numbers.

INT opens at 6* BTDC @ .050 and closes at 38* ABDC @ .050

So theres the 2 ways to degree a cam. Or you can line up some dots or zeros and say its??? depending on the cam and other stuff. mikre

Thanks for the input. I guess with somewhere just north of $6K pounded into this 'street' motor I want to make sure I cover all the bases. OOOPS! Hope my wife doesn't see this!