Cam tech - split-pattern vs regular pattern
Cam tech - split-pattern vs regular pattern Starting to roll back into the technical side of car modding prior to digging into my T/A, and one question I've come up with after reading some cam threads (and not seeing a whole lot mentioned about it) is the use of split-pattern cams. What are the benefits or disadvantages to using one? Are there any pre-requisites for selecting a split-pattern over a normal-pattern cam, like displacement, F/I, or nitrous use? Head design or benched flow pattern/volume for a specific style of head? Connected to that, reverse-split cams - same deal with those?
When I was still reading about engine guts a while back, the 224/224 and 228/228 seemed like the most popular, with the "monster" 232/232 being the bad boy of the pack...but I don't remember nearly as many of the favorite cams back then being split-pattern. Are they just more efficient at making power in the LSx engines given the advancement in LSx engine knowledge and mods today?
When I was still reading about engine guts a while back, the 224/224 and 228/228 seemed like the most popular, with the "monster" 232/232 being the bad boy of the pack...but I don't remember nearly as many of the favorite cams back then being split-pattern. Are they just more efficient at making power in the LSx engines given the advancement in LSx engine knowledge and mods today?
TECH Resident
Joined: Dec 2004
Posts: 845
Likes: 0
From: K-W, Ontario
This probably...defintely belongs in advanced tech., but I'll get the ball rolling.
* Allowing for more duration on intake, with less overlap (when called for in setup).
* Tailoring the cam to intake vs. exhaust flow and int/exh valve sizes.
* More flexibility with timing int./exhaust closing points.
All of the above and more. RPM, valve train design, exhaust system flow
and dimensions (primary and secondary tube lengths) to name a few.
What do you mean by this statement? Normally the reverse split is
used on engines with better exhaust flow and allow for enhanced
torque in the lower RPM range.
If there is less duration on the exhaust, it will allow the cam design to open
the exhaust valve later so that more of the combustion pressure is used to
force down the piston rather than blow out into the exhaust.
What are the benefits or disadvantages to using one?
* Tailoring the cam to intake vs. exhaust flow and int/exh valve sizes.
* More flexibility with timing int./exhaust closing points.
Are there any pre-requisites for selecting a split-pattern over a normal-pattern cam, like displacement, F/I, or nitrous use?
Head design or benched flow pattern/volume for a specific style of head?
Head design or benched flow pattern/volume for a specific style of head?
and dimensions (primary and secondary tube lengths) to name a few.
Connected to that, reverse-split cams - same deal with those?
used on engines with better exhaust flow and allow for enhanced
torque in the lower RPM range.
If there is less duration on the exhaust, it will allow the cam design to open
the exhaust valve later so that more of the combustion pressure is used to
force down the piston rather than blow out into the exhaust.
