Can anyone explain split duration reverse pattern cams to me?
Thread Starter
Team Owner
Joined: Mar 2001
Posts: 25,889
Likes: 7
From: Virginia Beach
CI 3-5-6-7-8 Veteran
Can anyone explain split duration reverse pattern cams to me?
I think I got that right... I've been reading posts about these new cams... how are they different? I understand the basics of a cam but what dows split duration and reverse pattern mean? Forgive me but is it like some kind of Vtec where the pattern changes for different rpm ranges?
Thanks,
B
Thanks,
B
Drifting
Joined: Feb 2000
Posts: 1,922
Likes: 0
From: Boulder, Colorado
Re: Can anyone explain split duration reverse pattern cams to me? (Cobra4B)
...what does split duration and reverse pattern mean? Forgive me but is it like some kind of Vtec where the pattern changes for different rpm ranges?
Before recently, any LS1 cam that wasn't a single pattern (identical intake and exhaust) had more exhaust duration. Now the 'reverse' is popular.
Safety Car
Joined: Nov 1999
Posts: 3,891
Likes: 2
From: Houston, TX
Re: Can anyone explain split duration reverse pattern cams to me? (Cobra4B)
Miles got it right.
What this exemplifies is just how good the exhaust ports are on the LSx engines. With the old SBC engines, the exhaust port was seriously deficient which meant that you had to give the exhaust a lot more time to evacuate than you did the intake to let the air in.
With the LSx engines/heads, the exhaust port was completely redesigned from the original SBC and they did a great job on it. Hence why you can now shorten the exhaust duration dramatically resulting in a better idle and no loss of power! :yesnod:
If you need any additional help, we would be happy to assist you.
Thanks,
What this exemplifies is just how good the exhaust ports are on the LSx engines. With the old SBC engines, the exhaust port was seriously deficient which meant that you had to give the exhaust a lot more time to evacuate than you did the intake to let the air in.
With the LSx engines/heads, the exhaust port was completely redesigned from the original SBC and they did a great job on it. Hence why you can now shorten the exhaust duration dramatically resulting in a better idle and no loss of power! :yesnod:
If you need any additional help, we would be happy to assist you.
Thanks,
