Page 1 of 1
EA81 no Y pipe twin system?
Posted: Mon Jul 18, 2011 8:24 pm
by Tweety
About to start my EA81 conversion in a few weeks into my trike. Am not desiring to use a "Y" pipe connector under my vehicle. Easier design wise to run each side of the exhaust to the side and under to an approapriate muffler then out.
Problem? Will the subie engine suffer from no Y pipe? Considering it will have to pass an engineer what type of mufflers are recommended that will quieten it enough to get over the line? I do desire twin system for appearance.

Posted: Mon Jul 18, 2011 8:48 pm
by apg39
I can't recall where I read it but the Subaru engines rely on the 2 pipes merging to assist scavenging, so yes will affect it & not recommended.
Posted: Mon Jul 18, 2011 8:57 pm
by TOONGA
you can use a similar system to what you have on the VW engine but add a balance pipe between the two exhausts, or find someone to fabricate a set of balanced turbo headers without the up pipe extension and have that run into a single exhaust mounted sideways like the combis.
I was trying to find an example of an exhaust for you but I couldn't find the one I was looking for but however I did find this
http://bb.bbboy.net/vwengineconversions ... &thread=82
have a look about half way down that thread for a set of insane y pipes and lots of other interesting mods to go with an EA81
TOONGA
Posted: Mon Jul 18, 2011 9:59 pm
by Tweety
thanks guys
ok so it seems the Subie engines need a pipe between them not unlike some old motorcycle engines. That's what I needed to know.
I've copied that odd looking but great exhaust system for my exhaust expert. He can make up some SS radiator pipes at the same time! I'll find an ideal location for the joining pipe underneath.
Posted: Mon Jul 18, 2011 10:26 pm
by steptoe
I hear the sound of a flat four with twin exhaust is a bit like a BMW with an experimental Orbital fuelling sytem - different
Posted: Tue Jul 19, 2011 8:15 pm
by Tweety
mmmm..so there' a challenge. the exhaust note! Suppose I'll chat with the exhaust guru and see if we can come up with a Y join somewhere. Wouldnt like an odd and rotten note.
As for Subaruenza re your signature Steptoe- I suggest Doobiedubbers!, Doubledubbers, scrubberdubber.....
Posted: Tue Jul 19, 2011 9:50 pm
by TOONGA
here is another exhaust system
stolen from here
http://bb.bbboy.net/vwengineconversions ... thread=169
it is on an EJ motor but it shows how you can do a dual exhaust with a balance pipe
it is nice and shiny as well
TOONGA
Posted: Wed Jul 20, 2011 8:56 pm
by Tweety
thats a work of art!
I like it and have pritned it out for the exhaust guy.
thanks again

:-D:-D:-D
Posted: Thu Jul 21, 2011 8:43 am
by TOONGA
not a problem
reading about these swaps gives me ideas for AWD subaru powered VW onroader/offroaders
anyone care to fund my obsessions
TOONGA
Posted: Thu Jul 21, 2011 5:34 pm
by El_Freddo
TOONGA wrote:
anyone care to fund my obsessions
Thanks but no thanks! I'm having enough fun trying to fund my own project!
Cheers
Bennie