Quote:
Originally Posted by wparsons
No. How much boxer rumble do you hear in any of these?
H6 swapped impreza (still a boxer)
Older 911 (yes, those are boxer engines too)
New 911 (yep, still boxers)
Yet another 911 (again, still a boxer)
There are two main reasons the (non FRS/BRZ) Subaru 4 cylinder boxers sound so different.
1) The stock manifolds are VERY UEL and merge the ports right at the head instead of having individual runners for each cylinder.
2) They have different firing orders than most engines, and fire both left cylinders then both right cylinders.
The firing order combined with the manifold design is why they rumble so much stock. If you swap out to an EL manifold you'll definitely get rid of the rumble. |
I think we're saying the same thing. In general, UEL doesn't make the boxer rumble. Just because a car has UEL headers doesn't give it a rumble-sound.
It's a combination of the flat motor and uneven length headers that makes the unique sound in boobaru's.