View Single Post
Old 11-18-2014, 08:54 AM   #177
Calum
That Guy
 
Join Date: Dec 2011
Drives: 2013 asphalt FRS MT
Location: Halifax, Nova Scotia
Posts: 4,865
Thanks: 5,058
Thanked 2,868 Times in 1,499 Posts
Mentioned: 82 Post(s)
Tagged: 1 Thread(s)
Quote:
Originally Posted by cdrazic93 View Post
but if the 4-1 manifold were designed in a way to pulse 4-2-3-1 in some calculated order, wouldn't that be close to if not the same thing?

edit: By no means am I saying Full Race has bad manifolds; if anything they have the best. That much can be concluded just with pictures, I'm speculating purely manifold style.
The length of the runners in an exhaust manfold along with the diameter of the tube, and a few other factors that are beyond this discussion will determine a resonant frequency in the tube. At certain engine rpms this resonance will cause a low pressure area at the exhaust valve which will greatly aid in scavenging. By having a 4-2-1 design they've made it so the runner can resonate ate two frequencies, which if designed correctly will give a broader power band.

Try these for some further explaination.

This one explains header design basics.

http://www.team-integra.net/forum/bl...powerband.html

This one is about intake manifolds, but it does a good job of explaining the resonances.

http://grapeaperacing.weebly.com/uploads/4/1/2/0/41206275/inductionsystems.pdf
Calum is offline   Reply With Quote
The Following User Says Thank You to Calum For This Useful Post:
cdrazic93 (11-18-2014)