info on cams
05-13-2008, 01:40 AM
#1
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info on cams
hi i want to know if any one here knows if there are any cams besides th jbp cams.....if not how well are the jbp cams.......also if i where to get cams could i run my stock cam gears or would it be best to replace them.....
05-13-2008, 11:48 AM
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I've gotta find someone who wants to sell just an exhaust cam.
I'm going to give the good old 272/264 a try this fall (on stock cam timing)
Less duration on the exhaust side, but i have a feeling that the decreased overlap could benefit us.
I'm going to give the good old 272/264 a try this fall (on stock cam timing)
Less duration on the exhaust side, but i have a feeling that the decreased overlap could benefit us.
Last edited by Omega_5; 05-13-2008 at 11:55 AM. Reason: typo
05-14-2008, 02:14 PM
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My JBP Stg2's are for sale WITH the Valve Springs. Never installed. $550 shipped for Cams and VS's... that's a fuggin deal.[/QUOTE]
why you sellin? that is a sweet deal, thats like 50% off lol
why you sellin? that is a sweet deal, thats like 50% off lol
05-14-2008, 03:15 PM
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Less duration exhaust side works against you on a supercharged car, I think you mean less on the intake side.
05-14-2008, 03:41 PM
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I believe we'd be dealing with 2 degrees of active overlap with a 272/264.
Really, it's not my idea... but the numbers looked so promising, that I said I'd try it one day.
As it was proposed to me;
We are limited by the problem that we are forcing air into the engine, but have no limitation on the exhaust side (as in no turbo to resist the exhaust flow).
Our solution, is to decrease the amount of blow though, due to valve opening overlap.
Let's experment;
272/272 cam profile is obviously where the problem starts. Running too much boost will simply set you back as your just blowing though a fair amount of useful air/fuel.
Try a 264/272 profile. The LSA on this combination is 3 degrees, and considering the profile of each cam, you are left with about 13 degrees of over lap. Obviously this system isn't too much of an improvement over the 272/272 combination.
Now try a 272/264 profile. The LSA on this combination is 4 degrees, and again considering the profile of each cam, you are left with 10 degrees of overlap.
This combination will provide a longer fill period, as well as taking advantage of the higher cylinder pressures on the exhaust side. The 264 profile tends to promote a more broad power band, including a strong mid range, as well as taking advantage of the higher flow and boost pressures at the top end.
Our solution, is to decrease the amount of blow though, due to valve opening overlap.
Let's experment;
272/272 cam profile is obviously where the problem starts. Running too much boost will simply set you back as your just blowing though a fair amount of useful air/fuel.
Try a 264/272 profile. The LSA on this combination is 3 degrees, and considering the profile of each cam, you are left with about 13 degrees of over lap. Obviously this system isn't too much of an improvement over the 272/272 combination.
Now try a 272/264 profile. The LSA on this combination is 4 degrees, and again considering the profile of each cam, you are left with 10 degrees of overlap.
This combination will provide a longer fill period, as well as taking advantage of the higher cylinder pressures on the exhaust side. The 264 profile tends to promote a more broad power band, including a strong mid range, as well as taking advantage of the higher flow and boost pressures at the top end.