newbie exhaust question... - Toyota Yaris Forums

tooter · 04-26-2012, 08:27 PM

I'll be happy to let you know how this little experiment goes. Many 4 cylinder stock exhaust manifolds employ the tri-y design for more bottom end so it's a tried and true principle. Here's a longer header that illustrates the principle more clearly...

...and a brief explanation:

"Tri-Y's consist of a four-into-two-into-one design, with four primary pipes paired into two slightly larger secondary pipes before reaching a single collector. One advantage of this design is that the increasing pipe diameter broadens the torque curve, providing higher torque throughout the low- and mid-rpm range than a similar four-into-one style header. Headers work especially well for RV's and trucks in which lots of low-rpm torque is important.

The principle behind tri-Y design is that the most effective port separation occurs by pairing the cylinders that are firing farthest apart, in other words 180 distributor degrees (or a complete crankshaft revolution) apart."

I understand that just installing a header won't make a huge difference, I've always been interested in exhaust designs so it's fun to tinker around with them. And as far as I know, Weapon R is the only manufacturer who makes a tri y for Yaris'.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Newbie with an exhaust leak on his '06 Yaris	ToYarta	DIY / Maintenance / Service	49	01-03-2019 01:50 PM
NEED ENGINE CHECK LIGHT CODE LIST	Attitude	Forced Induction Forum	12	04-11-2011 07:38 PM
Enkei's and Dunlops + Medalion Touring Exhaust	2manywheels	Items for Sale by private party	40	04-04-2011 06:01 PM
))) new TS exhaust question (((	aucorium	Performance Modifications	4	03-29-2010 02:21 AM
does BACK-PRESSURE increase MPG vs straight thru...	marcus	Fuel Economy Forum	25	05-03-2009 10:23 PM

04-26-2012, 08:27 PM	#19
tooter play every day Drives: 2012 Yaris L 2dr 5sp Join Date: Apr 2012 Location: Los Angeles Posts: 1,962	I'll be happy to let you know how this little experiment goes. Many 4 cylinder stock exhaust manifolds employ the tri-y design for more bottom end so it's a tried and true principle. Here's a longer header that illustrates the principle more clearly... ...and a brief explanation: "Tri-Y's consist of a four-into-two-into-one design, with four primary pipes paired into two slightly larger secondary pipes before reaching a single collector. One advantage of this design is that the increasing pipe diameter broadens the torque curve, providing higher torque throughout the low- and mid-rpm range than a similar four-into-one style header. Headers work especially well for RV's and trucks in which lots of low-rpm torque is important. The principle behind tri-Y design is that the most effective port separation occurs by pairing the cylinders that are firing farthest apart, in other words 180 distributor degrees (or a complete crankshaft revolution) apart." I understand that just installing a header won't make a huge difference, I've always been interested in exhaust designs so it's fun to tinker around with them. And as far as I know, Weapon R is the only manufacturer who makes a tri y for Yaris'.