FI Plenum Design, MS'ing my 2270 |
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FI Plenum Design, MS'ing my 2270 |
Tom Perso |
Feb 1 2005, 07:41 AM
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#1
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Crazy from the Cold... Group: Members Posts: 647 Joined: 8-August 03 From: Kalamazoo, MI Member No.: 1,003 |
Hey Guys,
I am designing a MS system for my 2270 (163.86b cam, 48x38 valves, future Triad header). I am looking at running stock intake runners and possibly making a new plenum to run my Ford TB (probably from a 4.0L Exploder/Ranger). Are there any "design guidelines" that should be followed when making a new plenum, such as a certian volume required for engine displacement? Looking at space requirements, I see running the TB on top of the plenum is the only way to go. That, of course - begs the question... Is the stock 914 2.0L plenum a good starting point to modify to allow for the Ford TB? Here are some pics for reference... I had a Bus 2.0L intake system to borrow, so I am basing my measurements and ideas off of that. http://www.qtm.net/~persot/MS/ Any ideas, suggestions, etc, are appreciated! Thanks, Tom |
airsix |
Feb 5 2005, 01:20 AM
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I have bees in my epiglotis Group: Members Posts: 2,196 Joined: 7-February 03 From: Kennewick Man (E. WA State) Member No.: 266 |
My input here won't be very scientific, but... When I was planning the turbo project I needed to move the TB to a location better suited for the turbo plumbing. This is on a 1.7 so the TB was horizontal on the driver's side. I cut my plenum neck off, rotated it 90 degrees, added about 1" to the length of the neck, hammered to shape, and rewelded it back together with the TB in the vertical possition. I estimated that I added about 5% to the plenum volume. The effect was a slight, yet noticable decrease in throttle response between about 2,700-3,100rpm. At other rpm's there was no noticable difference but it definitely lost some snap in that narrow rpm range. It was a little disheartening since that is typical cruise rpm and it's exactly the rpm I'm generally in when I decide to goose it. The good news is that for whatever reason, after increasing the plenum volume I was able to increase the timing advance by about 2 degrees (at that spot - not across the board) and got most of the snap back. I drove it like this for many months before the turbo was added. -Ben M. |
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