Q's on cam choice
#41
TECH Veteran
iTrader: (6)
Join Date: Nov 2003
Location: Tallahassee, FL
Posts: 4,397
Likes: 0
Received 0 Likes
on
0 Posts
No, everything was made up in that example...LOL, Don't follow it for its data. The main point is that a given intake lobe needs so much exhaust to work within a certain RPM range.
When you have too much exhaust, idle and low speed cruising may suffer as well as power is pushed higher in the RPM range as my example tries to show.
Flyer could run 2'' exhaust tubing and his idle would improve just like when he closes the cut-outs... (Another example)
When you have too much exhaust, idle and low speed cruising may suffer as well as power is pushed higher in the RPM range as my example tries to show.
Flyer could run 2'' exhaust tubing and his idle would improve just like when he closes the cut-outs... (Another example)
#46
TECH Senior Member
iTrader: (6)
Join Date: Jul 2005
Location: Decatur, AL
Posts: 5,257
Likes: 0
Received 0 Likes
on
0 Posts
Lift has basically no effect on cam manerism or power band. You just get less valve shrouding of the hole with the more lift which equal more air flow. Several mechanical interferences and reliability issues is what limits lift.
#48
TECH Veteran
iTrader: (6)
Join Date: Nov 2003
Location: Tallahassee, FL
Posts: 4,397
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by LS1TRUCKGUY
Would It Be Possible To Run A Small Duration High Lift Cam And Get Good Power From It As You Would A Big Duration And Smaller Lift Cam? so a big duration and low lift cam is more reliable? are you talking piston to valve clearance?
It's very much possible. Reducing seat-seat time and increasing the ramp rate of the intake lobe works great. Lift is a by-product of the lobe profile and ramp rates in most scenarios.
A faster ramp puts the valve where it needs to be quickly. The 5.3L head flows 225CFM from .500'' valve lift to .650''. Get it their fast, and hold it their for as long as possible.
This works great for 'big' power and decent drivability. For a given LSA, less seat-seat timing means less overlap.
Last edited by Sport Side; 01-13-2006 at 06:10 PM.
#49
TECH Fanatic
Join Date: Oct 2002
Location: Dallas, North Mexico
Posts: 1,842
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by LS1TRUCKGUY
Would It Be Possible To Run A Small Duration High Lift Cam And Get Good Power From It As You Would A Big Duration And Smaller Lift Cam? so a big duration and low lift cam is more reliable? are you talking piston to valve clearance?
This is the reason why solid rollers make so much more power. Cam profile
Thread
Thread Starter
Forum
Replies
Last Post