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

[914efi]

SDS has an option for locking in a fuel value at a certain throttle position. I did this for while but gave up on it because as soon as you opened the throttle and moved off the locked value, it would revert to the MAP signal and cause a sharp jump in the fuel value. This made low speed driveability poor. If you need to have a very different idle fuel amount than is given by the proper tuning of the MAP signal, you will have this jumpy condition.

SDS is not good for low speed driveabilty with engines that have low idle vac (like my 2.2E). I think the 2D map like mega has is a better solution for these engines. You will notice that almost all of SDS projects posted are turbo engines. I am still running SDS and it works pretty well, but I would like to change to mega at some point. The SDS is so easy to tune that I am not looking forward to losing that. I would have to piggyback the mega onto my SDS crankfire system I think. I have not looked at what is involved in using the mega ignition.