HKS 264's VS GSC S2's For DSM

[VETDRMS]

That you would like me to clarify an intuition:
I've seen graphs of flow bench, I realize that this HKS 272 at the edge of the valve lift and cfm peak.
This suggests to me that cams with more lift than the peak cfm would cause losses on stock head?
For example using kelford 272 in the head stock, it would be worse than using HKS 272. Even kelford a command that comes with more gains .. correct?

Even if you open the valve past the peak "lift-cfm" you still get the benefit of a faster opening ramp rate, meaning the delta between seat-open and open at peak cfm is smaller. Therefore you get more time at, or near, peak cfm. Which typically means more power.

 

[NDgsx]

So we just did a test on the HKS 272 (full set, not 264/272 in this test) and had very surprising results. I am Johnbradley on that forum-

Old test done again HKS 272 VS GSC S2 30hp gain - evolutionm.net

I will also move those results over here for discussion. Max lift vs max flow is easy really. Normally our heads plateau at 10.8-11mm lift. More lift doesnt mean less air, it just doesnt mean more air. So for a given duration more air is still going on in if the lift is higher. This allows the engine to run a slightly smaller cam without having idle issues.

 

[keltalon]

No it does not have adj cam gears. Good cams should not need them.

I love reading the older threads!. Yeah no cam needs a degreeing with modern technology and especially with today's ability to tune our own cars. I have spent many hours degreeing a set of new upgraded cams only to find out that after the dyno the cams yielded more power , not from degreeing them but by setting them according to a setting that the car really liked. After several attempts degreeing a set of cams with the same senario I stop wasting the time to degree and started by setting them on zero and tuning from there !

 

[autotalon]

I had a similar experience with my own set up. Went from kelford 264/260's to the s-2's and matching springs and picked up 75 whp. I also switched from a re-circed o2 housing to a external dump, so don't know how much that accounted for.

 

[Fullthrottle7]

After several attempts degreeing a set of cams with the same senario I stop wasting the time to degree and started by setting them on zero and tuning from there !

That is the point of degreeing (degreeing = getting to actual centerline of cam). Lucas was simply saying that any quality cam should be able to be installed straight up and be on centerline and that lesser quality cams are ones that need to have the time spent to get there before actual changes can be played with. You may buy one set of BC cams and install them straight up and do the same with another and be a cumulative 8-10* off from each other. Starting at zero for each set AKA degreeing IS needed on these cheap sets if you want to be able to give comparable results. That is not the same as saying that once each individual set of cams is installed at their centerline that it will perform at its maximum ability since you may consider a quicker spool to be "better" while another may want the most top end available and retard/advance each cam with adjustable gears to suit their needs.

I get what you are saying and have watched you tinker with each setup to make it the "most streetable" which is cool, but to insinuate that the ideas presented in this thread were wrong isn't really true... The settings that you found to be optimal in each of your cam tests wouldn't necessarily apply to every set of sticks in the cheaper brands because their centerlines are not consistent. For the more QC minded companies like GSC or HKS etc. though, what you find to be optimal after playing with timing should pretty well apply accross all of that same set for other people.

Just trying to make sure new guys who read this and follow your other posts aren't buying some of the cheaper sets and a set of cam gears and using the same settings as you wouldn't want anyone's pistons to meet their valves more formally than close neighbors ...

 

[keltalon]

That is the point of degreeing (degreeing = getting to actual centerline of cam). Lucas was simply saying that any quality cam should be able to be installed straight up and be on centerline and that lesser quality cams are ones that need to have the time spent to get there before actual changes can be played with. You may buy one set of BC cams and install them straight up and do the same with another and be a cumulative 8-10* off from each other. Starting at zero for each set AKA degreeing IS needed on these cheap sets if you want to be able to give comparable results. That is not the same as saying that once each individual set of cams is installed at their centerline that it will perform at its maximum ability since you may consider a quicker spool to be "better" while another may want the most top end available and retard/advance each cam with adjustable gears to suit their needs.

I get what you are saying and have watched you tinker with each setup to make it the "most streetable" which is cool, but to insinuate that the ideas presented in this thread were wrong isn't really true... The settings that you found to be optimal in each of your cam tests wouldn't necessarily apply to every set of sticks in the cheaper brands because their centerlines are not consistent. For the more QC minded companies like GSC or HKS etc. though, what you find to be optimal after playing with timing should pretty well apply accross all of that same set for other people.

Just trying to make sure new guys who read this and follow your other posts aren't buying some of the cheaper sets and a set of cam gears and using the same settings as you wouldn't want anyone's pistons to meet their valves more formally than close neighbors ...

I fully understand what you are saying I certainly don't want to confuse or mislead and definitely don't won't any pistons kissing valves! Each has methods of tuning that others may not understand. thanks!