I've been playing with the idea of retarding my cam. Dyno2003 shows an increase when retarded 2 degree's.

Cam specs:

214/224

IVO: 0
IVC: 34

EVO: 49
EVC: -5

My question is, would this be a worth while thing to do. I have the engine still at the point that I can do this easily (err, get to the cam i mean), and I have not broken in the cam nor the motor yet. If I dont retard the cam, and I want to do it later after I break in the cam, do I have to break in the came again after the retard cahnge?

If I do retard the cam, does that have any effect on the ignition timing? For example, if I set it to 22 degrees, then retard the cam, will I have to adjust the ignition timing up or down at all?

 

ok first you do not have to re-break in a cam when you change the cam timing since you are not changing anything physically just moving it.

your ignition timing has nothing whatsoever to do with cam timing. ignition timing is the timing in relation to the pistons postition in the bore. you still run the same timing you ran before changing the cam timing. you will need to reset it though back to your setting you want it at.

by changing the timing of the cam, retarding the cam timing generally causes a drop in torque in the bottom end and middle rpm range where as advancing the cam will give an increase in bottom to mid range torque. most cam companies sell their off the shelf cams (ex a comp cams 268 hydraulic) already ground with 4 degrees of advance built in, so advanceing that cam 4 degrees would esentially mean your now at 8 degrees advance on the cam.

unless you have a degree wheel and the tools to degree a cam in properly id would just line up the dots on the cam for strasight up cam timing.

 

Gonna take a wild stab at this and all...but since the dizzy drives off the cam, my guess is iginition timing will be affected...also, changing cam timning will most likely require a different ignition timing curve/total as well, since you've change the charateristics of the motor/

But what do I know.

On a side note, if you have the ability to change cam timing, what's the big deal with adjusting iginition timing?

As another side note most all street motors respond better to advancing the cam to get to the usable power lower in the RPM range...I might think of retading a cam if I had a boat and it spent it's life at WOT.

I'll go a step further and note that many street cams have advance ground into them.

Good luck, just a yacking on the boards

 

Retarding the cam timing a few degrees can shift the torque curve out to higher rpms, possibly resulting in more power. Itll come at a cost to low end performance. Id jsut set it to whatever was recommended and leave it.

 

Guess i'll leave it in then. I will get dyno numbers, then retard it later and dyno it again to see what the change is.