I'm looking at getting an XE 216 114 cam for my home port job and was wondering what exactly happens when you advance/retard a cam...Yeah, I know the basics, advanced moves the band lower and vise versa. Dont most people get 4 deg ground in to account for some timing chain stretch and to make the power more usable in lower rpms. Does 4 deg. sound good for a cam this size? Also, does having the cam advanced more cause the idle to diminish slightly? 4 deg advanced would give me 110* ICL right?

Brad

 

I know somebody out there has some input on this.

Brad

 

I will bring this to the top for you.

Dont know whether more "built in advance" changes idle quality or not. Maybe someone else can help answer that.

You are right about figuring ground in advance. A cam with 114 LSA and an IC of 110 degrees would have 4 degrees ground in advance. At least thats what I understand.

Most of the Comp Cams I have seen talked about on this board have anywhere between 2 and 4 degrees of advance ground in.

Lets say we take two identical duration and lift aftermarket cams. One with 2 degrees built in advance, and one with 4. Install them both dot-to-dot.

1. Which one will give the best part throttle response (daily driving mode)?

2. How about max HP/Torque?

3. Which will idle the smoothest?

Anyone have some input?
Ron,

<small>[ May 03, 2002, 09:53 PM: Message edited by: Kimchee and Rice ]</small>

 

Well, I had to order my cam today and I got it with 3* advance. That'll give me 111 IC.

Brad

 

what gears do you have in the rear end? auto or manual? Stall if auto? Ls6 intake? Timing chain? This would help us out... Im curious too, interesting ....

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by blazinredls1:
<strong>what gears do you have in the rear end? auto or manual? Stall if auto? Ls6 intake? Timing chain? This would help us out... Im curious too, interesting ....</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">4.10s, M6, LS6 intake, stock timing chain-hence the extra need for ground in advance, stock exhaust manifolds.

Brad

 

The Comp Cams catalog states that all of their High Energy and Magnum cams are designed with 4 degrees advanced already ground in.

My own experience with an old 400 Pontiac engine with advancing and retarding the cam (using a seat of the pants meter):
Straight up; runs good throughout the RPM range.
4 degrees advanced; very good bottom end torque, did not loose much, if any, on the top end.
4 degrees retarded; lost bottom end torque, top end was noticeably more peaky.
After the testing I liked the 4 degrees advanced the best for this engine.

MyLS1Hauls and Kimchee and Rice had some excellent questions. Does anyone have any answers?

 

2 degrees to account for chain stretch is sufficent for a small cam such as a 216. Even if over time it ends up retarded by a degree, the power band will be fine with a 6400 shift point.

 

I agree with Ragtop, to me 4* advance would be better suited for larger duration cams, bigger than 220* at .050". I think head flow has the most influence on where you want max lift to take place in relation to piston position.

 

I would go ahead and put +2 degrees advance in the cam.I Dont think it really could hurt you and with the 4:10's if would be cool to see it, as long as you could wind out fourth which you should depending on fourth. What do you shift at now? Do you had the car on a dyno? I am thinking with jason's post recently , the tighter the LSA the more the ls1 likes it and with the 114, it should be worthwhile.

 

Well damnit, my cam came in as a 114+4. I made a mistake when ordering..I thought I was getting 3 deg advance. I'm sure the extra degree wont be noticeable over the 3. I am debating getting the SLP adjustable unit for reliablity and also to move this cam back to a 112 ICL. How do you adjust the SLP unit? Thx.

Brad