Any cam that increases power within stock rev range?
12-26-2006, 10:10 AM
#16
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12-26-2006, 10:20 AM
#17
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You would never, ever notice the difference between a 210/224-112 cam and a 211/219-112 cam. 1 deg on the intake and 5 on the exhaust is nothing.
IVC is Intake Valve Closing - the single most influencial aspect of a cam. This, more than anything else, will determine the rpm range the cam will make power in. Stock, as well as the 227 cam and the LPE RV cam hold this value right around 33 deg ABDC. More aggressive cams that rev higher are 40 - 45, while many race cams are 45 - 50. It's pretty rare that an IVC greater than 50 is useful for us.
Mike
IVC is Intake Valve Closing - the single most influencial aspect of a cam. This, more than anything else, will determine the rpm range the cam will make power in. Stock, as well as the 227 cam and the LPE RV cam hold this value right around 33 deg ABDC. More aggressive cams that rev higher are 40 - 45, while many race cams are 45 - 50. It's pretty rare that an IVC greater than 50 is useful for us.
Mike
12-26-2006, 11:50 AM
#18
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http://store.summitracing.com/partde...779LUN&FROM=MG
power range is 1600-5600, so pretty close to stock
215/224, .489/.489 (factory ratio)
power range is 1600-5600, so pretty close to stock
215/224, .489/.489 (factory ratio)
12-26-2006, 06:05 PM
#19
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A few degs here and there is a little more than nothing. Most guys will not notice it but the people designing the cams will. 5degs on the exhaust can make a big difference..... and IVC is important but you can't just take that one spec and think it's going to determine the entire actions of the motor... it's just not that simple.
Bret
Bret
12-26-2006, 06:46 PM
#20
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Okay, let me play devil's advocate here. Just how much power, torque, and rpm range difference do you think there will be between 210/224-112 and 211/219-112?
I'm sure there are some cases out there where 5 deg exhaust duration makes a big difference, but in every dyno test I've seen, 10 deg exhaust duration, particularly if on the EVO side, is barely even noticable on the dyno. In one test in particular, when a very powerful and popular LS1 grind was in development, adding 10 deg to the EVO lost a few ft-lb below 2500 rpm and added a few hp beyond peak. It wasn't enough difference for me to get excited over. On the EVC side, the difference was a little more dramatic, but again, nowhere near as influential as small changes to the IVC.
I believe my statement was, "IVC is . . .the single most influencial aspect of a cam. This, more than anything else, will determine the rpm range the cam will make power in." Notice I never said that the other timing events are not important, or that IVC determines everything.
Mike
Mike
12-26-2006, 07:58 PM
#22
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That LPE cam has the highest lift, so compared to the Crane 227 and the Lunati 54779, wouldn't it develop the most power? I mean, given that the timing events of the 3 cams are pretty similar, wouldn't the .533/.560 lift (with 1.6s) give the LPE the advantage?
12-26-2006, 08:25 PM
#24
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i think it does however i am biased. especially since i've never been up against other "emissions legal" heads/cam LTx packages that have done well against my setup whenver i would go to the track. there are a GAGGLE of LT4 heads/cam packages but i've never witnessed any get into the low 12's or high 11's.
12-26-2006, 08:39 PM
#25
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That's pretty sad when myself and 2 other local guys (including Frank95Z) have been low 12's or quicker (much quicker in Franks case) using the little 210/224 Crane and stock heads.
12-27-2006, 12:20 AM
#27
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