FI Plenum Design, MS'ing my 2270 Options

[Tom Perso]

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

[DNHunt]

Tom

Don't give up on this. I believe there is an option in the MS and S extra code that allows you to run a combination alpha-N and speed density in the fuel map. Alpha-N plots throttle position against rpm and speed density plots vacuum against rpm. I have not looked into it but, I assume it allows you to tune the idle independent of vacuum and switch to vacuum at some defined rpm. I know there are some pretty impressive cars that run a similar system.

That might solve the idle issue but, you still need to find a plenum solution.

Dave