OK I'm installing my Trickflow stage 2 cam in a 351 w with twin turbos and would like your suggestions on cam degrees? What would you suggest install it 0 , advance or retard???


Cam specs
Lift Duration
Intake 542 286
Exhaust 563 294

I think it is a 114 degree center

Your thoughts a much appreciated
Kerry

 

:withstu:


Shahram

 

Kerry... Why go with the Trick Flow 2 cam? Dont you have friends that work @ Cam Motion? Just wondering



Jeremy

 

It's all about saving a few nickles and I"m having him cut me a cam for the Dart Motor?? I figured the Trick flow cam would reach the limits of this block.

Can't believe you guys don't have more suggestions

Come on.....

 

Quite honestly, the bottom line is no one can tell you whats going to to work best.

Generally speaking, retarding moves the powerband up, and advancing moves it down. However, it has been found this is not always the case.

Therefore, my personal suggestion to you is to either run it on the dyno and try different settings, or install it straight up, just as the cam designer originally intended it to be used.

And, when I say "install" it straight up, I mean DEGREE IT IN straight up, not just line up the dots and call'er good.

 

What are the duration numbers at .050 lifter rise (the only that means much when comparing cams). Most turbo engines like about 4-5 degrees advance in order to build low end torque and let the turbos build the top end. Keep in mind that intake closing is always the most important timing event in the cycle.

Bryan Conner

 

The intake valve closing event is indeed arguably the most critical aspect of cam design, however....

You should never have to deviate ±5º from straight up when installing a cam. First off, blindly instalilng the cam that far off based on a generalization is not a good idea. Furthermore, even if it is determined after sufficient testing the cam in question works best installed that far off, you *clearly* are using the wrong cam for the application.

Now, I just looked up the specs for this cam and they are as follows:

Duration at .050 inches Tappet Lift
Intake - 224 degrees
Exhaust '“ 232 degrees

Valve lift with a 1.6 Rocker
Intake .542 inches
Exhaust .563 inches

Advertised duration at .004 inches of Tappet Lift
Intake '“ 286 degrees
Exhaust '“ 294 degrees

Lobe Centerline separation 112 Degrees

I am going to reassert my opinion of degreeing this cam straight up. I definitely don't think you want to advance or retard it 4 or 5º!!! Unless of course you are planning on pulling it to over 7000.

 

also depends on the cams origin...for example, lunati cams are 4 degrees advanced when its "straight up"...

 

Most of my experience is with extremely high boost (80-90 psi) alcohol engines and we use more duration on the intake side in order to run positive intake pressure differential. Three turbos (2 low pressure top turbos feeding one bottom high pressure turbo)

Most of these cams are ground from the so called experts (which I most certainly do not claim to be) with 4-5 degrees of advance ground into them. Also we run anywhere from 262-288 degrees of duration, so I may be completely wrong on what I am assuming concerning a street engine. Also we use anywhere from 112 to 116 degrees of lobe seperation.

These are long stroke, long rod engines with good flowing billet cylinder heads and are built to turn a max of 7000 rpm (5.5 stroke, 4.875 bore) and pull to a max torque peak of around 5000-5500 rpm.

The one down side to advancing the cams on a turbo street engine may be the ability to hook the torque to the ground on street tires.

Sorry If have steered anybody wrong.

Bryan Conner

 

hey kerry, i would have my cam degreed in. that way it is put in the motor the way it was designed for. no guessing.