Subaru mechanic employed by Timmons Volkswagen/Subaru in Long Beach
California. He is however, a strict advocate of maintaining a cars' stock
configuration!
Do not waste your time swapping 2.5 heads on the 2.2 turbo motor it will not
run much better. The NA on the 2.5 head stands for normally aspirated,
something like that. The 2.2 turbo is a very strong motor, better than the
2.0 WRX motor. The 2.0 was first used over 10 years ago, only minor changes
such as fuel and emission upgrades. Steve
Thank you for the feedback Steve. That may be taken as a challenge by
somebody to prove otherwise.... At least I hope so!
Second reply was from Matt Walters. Matt has countless thousands of dollars
worth of mods on his 270 horse 2.2 Turbo Legacy
From: jonesboy@sunwave.net
To: Ssspoon@aol.com
At 011 AM 29/03/2001 -0500, you wrote:
>Wild Bill Robinson, who may have enough stealth equipment to be considered a
>risk to national security wrote; "I know that my son's heads say "NA" on
>them, which I would interpret as standing for "naturally aspirated" i.e.
>non-turbo." (Can someone confirm this for Bill? Are we ruling out NA for
>North America?)
I believe that the NA does indeed stand for Naturally Aspirated.
>Then he asks; "Does anyone know for sure how the WRX solid lifter equipped
>quad cam heads differ from their NA counterparts?"
Double valvesprings come to mind - they're tougher and sprung
harder as well. The cams are also longer-duration and are probably also
made out of tougher stuff. The heads are basically p&p from the factory as
well - flow is important seeing as there's not a tonne of work they're
allowed to do to the internals things for WRC.
I seem to recall something about the lifters as well, but it's
slipped at the moment.
>I like this question because a few days ago I asked for feedback on the
>potential for a WRX 2.0 head swap vs. a 2.5 swap onto our United States
>version 2.2 Turbo Legacy blocks. This is while making the assumption that the
>2.0 efficiency should be comparable or better than the 2.5 since the 2.0 WRX
>engines were probably designed as recently as the 2.5 engines plus they were
>designed with performance in mind rather than shuttling the family to church.
I suspect that if the 2.0L heads are compatible they'll be a much
better choice than the 2.5L heads for pretty much that reason.
Think about it: the 2.0L heads are designed to flow for ~280HP for
the STi models. The 2.5L heads only have to flow 165HP.
In my mind, the choice is clear.
>It may also help to know if there are any differences in head configuration
>amongst the various WRX versions or at least whether they are all
>interchangeable.
My understanding of the matter is that all WRXs of a given MY have
the same head configuration - but I may be wrong.
I've got a sneaking suspicion that they change the cams between
WRX and WRX-STi.
>Anybody with a pipeline to the braintrust at Subaru (or anywhere) please
>inquire.
>
>Meanwhile I will copy this to Cobb Tuning, MRT Performance, Byron Leggett,
>Steve Powell, Matt Walters, Matt Scicchitano, and Simon Sirin. Can any (or
>all) of you gurus help with the above questions for us please? Us being
>members of a Turbo Legacy/Liberty enthusiasts web list, found at:
I'm a member of the Turbo Legacy ML too
-=[Matt]=-
Vice President, Software Design
Advanced Ideas Inc.
(250)833-9305
Thanks Matt. That makes two more who say NA for normally aspirated. But I
can't help wondering why that would be indicated, since there are no turbo
2.5's from which to differentiate. They're A*L*L normally aspirated !!!
Also Matt says the heads are p&p (ported and polished) from the factory. Wow
you think so? That would really surprise me since porting and polishing is
such a labor intensive precision hand machine work operation. Maybe they
take extra pains in designing the casting tool to give a super surface.
Anyone out there with port and polish experience that thinks some more horses
can be found?
That's it for this edition List Members. I'll be forwarding any further
replies as I receive them. Meanwhile, stay tuned. Larry Witherspoon
------------------------ ---------------------~-~>
Make good on the promise you made at graduation to keep
in touch. Classmates.com has over 14 million registered
high school alumni--chances are you'll find your friends!
http://us.click.yahoo.com/03IJGA/DMUCAA ... /X7OVlB/TM
---------------------------------------------------------------------_->
To unsubscribe from this group, send an email to:
BC-BFLegacyWorks-unsubscribe@egroups.com