The Subaru SVX World Network   SVX Network Forums
Live Chat!
SVX or Subaru Links
Old Lockers
Photo Post
How-To Documents
Message Archive
SVX Shop Search
IRC users:

Go Back   The Subaru SVX World Network > SVX Main Forums > MOD Mania > Proven Engine Enhancements
Register FAQ Community Calendar Today's Posts Search

 
 
Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #11  
Old 02-26-2008, 06:46 PM
RallyBob's Avatar
RallyBob RallyBob is offline
Registered fabricator
 
Join Date: Feb 2008
Location: Pleasant Valley, CT
Posts: 277
Next phase of development...

After the oil pan gets built, and (hopefully) the oil temp/coolant temp issues are handled, then we're going to strive for some more power as well as mid-range torque.

Jack had previously chopped up a spare stock EG33 intake manifold, and I got to looking at it the other day. In terms of basic design, it looks very good, there are very generous transitions from the plenum to the runners...factory 'trumpets' if you will. The crossover valve is a moot point for our application. The engine's running vacuum is already lower than standard, and the engine rarely sees low rpms on the track. So the crossover is always open as it is. As well, the intended original application was for a relatively heavy Grand Touring vehicle with an automatic transmission, so down-low torque was a priority to the engineers.

None of those factors apply now, so my thoughts are to eliminate the crossover, and utilize one common plenum at all times. A trial bit of math also shows that the plenum volume is very small relative to the engine's displacement. I'd like to investigate the effects of changing the plenum volumes to work with the improved breathing and extended powerband of the modified engine. If possible, I'd like to make it modular (bolt-on plenum addition) for testing, so I can determine which is best for our needs. Then , once the proper plenum volume is determined, I'll make a permanent version with reworked (slight porting and polishing) internal runners.

I'm thinking of trying 80%, 90% and 100% plenum volumes...2.64 litre, 2.97 litre, and 3.3 litre. Plus or minus a few CC's....

The first step will be to CC the stock plenum, and go from there.

It won't be tomorrow, but over the next 4-6 weeks I'll see if I can free up some time to tackle this project, and will post the progress here.

Bob
Reply With Quote
 


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -6. The time now is 08:40 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
© 2001-2015 SVX World Network
(208)-906-1122