ADVANCING CAM/ TETARDING WHAT HAPPENS TO POWER CURVE
12-12-2002, 05:20 PM
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ADVANCING CAM/ TETARDING WHAT HAPPENS TO POWER CURVE ITS A 224/224 .561/.561 114LSA
WHEN ADVANCED WHERE DOES THE POWER CURVE GO. moRE LOW END RIGHT? iF SO HOW MANY DEGREES SHOULD I GO FOR A MODERATE STREET CAR?
tHIS CAM WOULD BE USED IN A 98 CAMARO WITH STAGE 2 CNC HEADS AND MOST BOLT-ONES-IF YOU DO NOT THINK THIS CAM IS A GOOD CHOICE PLEASE RECOMMEND A DIFFERENT ONE.
WHEN ADVANCED WHERE DOES THE POWER CURVE GO. moRE LOW END RIGHT? iF SO HOW MANY DEGREES SHOULD I GO FOR A MODERATE STREET CAR?
tHIS CAM WOULD BE USED IN A 98 CAMARO WITH STAGE 2 CNC HEADS AND MOST BOLT-ONES-IF YOU DO NOT THINK THIS CAM IS A GOOD CHOICE PLEASE RECOMMEND A DIFFERENT ONE.
12-12-2002, 07:24 PM
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Re: ADVANCING CAM/ TETARDING WHAT HAPPENS TO POWER CURVE we seem to have a hard time getting people to answer cam questions. but yes, you are correct, advancing it gives you more low end. But that's about all I can tell ya. <img border="0" title="" alt="[Razz]" src="gr_tounge.gif" />
12-12-2002, 07:31 PM
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Re: ADVANCING CAM/ TETARDING WHAT HAPPENS TO POWER CURVE Argon, you might wanna check out my post about the lsa discussion. You will get all of your questions answered there I think.
12-14-2002, 12:44 AM
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Re: ADVANCING CAM/ TETARDING WHAT HAPPENS TO POWER CURVE Argon,
You are correct that you will improve low end torque by advancing a large duration cam such as the 224 degree one you have. As a bonus, the idle quality improves and surging is reduced. The opposite takes place when the cam is retarded.
Many cam manufacturers offset the dowel or keyway on their larger cams so that when you install your timing chain "dot to dot" your cam will automatically be advanced.
It is VERY IMPORTANT however that you check your cams timing specs either by the card that came with it, or better yet with a degree wheel. I installed a 224/224 @ 114LSA cam from MMS which was ground at a 115 degree ICL. (Grind #LS1 3314/3314 HR114-1 .569" lift). That indicated 1 degree of RETARD was ground into the cam with the intent of raising the rpm band for use with large port heads. An aftermarket timing chain was used in the 4 degree advance position to net an advance of 3 degrees on the cam.
The common amount of advance "ground in" is 4 degrees. That amount seems to be the best compromise to regain low speed torque when a relatively large cam is used for a given engine displacement. A few degrees less for a milder cam or a few additional degrees for a very large cam may be the optimum setting for street use.
<small>[ December 13, 2002, 12:55 PM: Message edited by: GTO69JUDGE ]</small>
You are correct that you will improve low end torque by advancing a large duration cam such as the 224 degree one you have. As a bonus, the idle quality improves and surging is reduced. The opposite takes place when the cam is retarded.
Many cam manufacturers offset the dowel or keyway on their larger cams so that when you install your timing chain "dot to dot" your cam will automatically be advanced.
It is VERY IMPORTANT however that you check your cams timing specs either by the card that came with it, or better yet with a degree wheel. I installed a 224/224 @ 114LSA cam from MMS which was ground at a 115 degree ICL. (Grind #LS1 3314/3314 HR114-1 .569" lift). That indicated 1 degree of RETARD was ground into the cam with the intent of raising the rpm band for use with large port heads. An aftermarket timing chain was used in the 4 degree advance position to net an advance of 3 degrees on the cam.
The common amount of advance "ground in" is 4 degrees. That amount seems to be the best compromise to regain low speed torque when a relatively large cam is used for a given engine displacement. A few degrees less for a milder cam or a few additional degrees for a very large cam may be the optimum setting for street use.
<small>[ December 13, 2002, 12:55 PM: Message edited by: GTO69JUDGE ]</small>