914 FI as a starting point

[fusername]

As a pure thought experiement, how is the 914 intake setup for a MS conversion? I have most of a 914 2.0 fi system, intake runners and cetner section, injectors and the brain, but no sensors or TB to speak of. I have a long term project on the brain for a bus motor, 76-84mm stroke, 94 mm bore, 914 2.0 heads. i want a low end grunt, and cool running all day long so FI seems the safest thing on such a strange motor. Would the 914 intake tract be a good starting point for someone to put together a simple FI system? or will dual webber progressives or a set of 40 dells be better bang for the buck?

I guess I am most interested in the practicality of the 914 intake, or are long runners and a cetner manifold not compatible with MS? just trying to get my feet wet in thinking FI. electronics don't scare me, but spending a couple hundred to a thousnad dollars to end out with somethign that runs as well as a center mount progressive would be a very dissapointing end to a build.

[tango]

That is what I started with on my MS conversion from dual Dells.

The plenum and runners are probably best suited to /designed for the 1971cc and characteristics, so possibly not optimum with the different config you mention but probably not noticeable without spending on dyno time. The 914 2.0 plenum is considered slightly inferior for NA peak power.

I cut off the 2 bolt flange and replaced it with a 4 bolt flange to mount the TB I got off Ebay complete with TPS and cold start valve, with an extension tube between them to mount the IAT. I blanked the other fittings except for a single vac line.

At the heads I opened out the injector openings to fit modern bosch type injectors and cut up and welded an Audi fuel rail to to mount the bosch injectors onto the existing studs.

Works great.

Oh, don't forget to add a turbo.

[fusername]

so are you saying it will limit upper end power? thats ok with me, call 5k my redline.

[raygreenwood]

I would say that Tango is pretty much on the mark. The 2.0 914 center plenum has a few issues with shape. It works but its TB entrance angle is not as advantageous as the 1.7/1.8 plenum. But...the plenum from the 1.7/1.8 is too small. See if you can get ahold of a 2.0 bus plenum and mode it to fit the runners.
Or....if you can make a splitter or pyramid to go under the down draft TB of the 2.0 914 plenum....that will help....as will a bit of a stand off tube between TB and plenum to allow a little bit of disippation of the turbulence plume from the TB. Ray

[fusername]

with the realtive ease of finding bus parts, I would probably just hunt down another 2.0 bus center section and TB and mate it to the 914 runners. This sounds very promsinig to me. One day I will do fI either on the big motor i just mentioned, or it just occcered to me on a T4 in a square, cause I don't wnat to do a tall decklid to make carbs work. I am picking up a square project car pretty soon if thigns go well, so this fi may happen sooner than i thought...

[Sneaks]

So I wonder who will go turbo first....

[Piledriver]

with the realtive ease of finding bus parts, I would probably just hunt down another 2.0 bus center section and TB and mate it to the 914 runners. This sounds very promsinig to me. One day I will do fI either on the big motor i just mentioned, or it just occcered to me on a T4 in a square, cause I don't wnat to do a tall decklid to make carbs work. I am picking up a square project car pretty soon if thigns go well, so this fi may happen sooner than i thought...

I promise I'll post pics of my T4-in-a-squareback this weekend.
I'm hoping to get it inspected this weekend, but had to work tonight, we'll see.

It's been running for a few weeks, the only issue I'm having now is the MAT and CLT readout is totally wrong, but hacking the curves with TS works well enough to allow good cold starts/warm up at ~38F.
(coldest it's been so far, this AM)

I used 2L runners and a widened Wasser plenum/TB, the holes on the flywheel for clutch venting are the "wheel" and I'm using a neutered Hall effect late Vanagon distributor (3 of 4 "wings" cut off" for TDC#1 sync. MS2 sequential fuel and CNP...)

For the whole thread laying out the good bad and the ugly...
http://www.shoptalkforums.com/viewtopic ... 3&t=131803

[fusername]

very fun, I have a NOS 1.9 dizzy i had planned on using on my big t4, but I think it will be better suited for this? just use the build in curve for now, upgrade the spark itself. go to comp controlled later. budget budget budget, I am a scrounger so if I can't get it for free or build it myself, it always takes a while.

see sneaks, i have no choice, gonna just have to go turbo eventually.

[aircooledtechguy]

I have used a Porsche 914 2.0L in my '67 Square and it fits under the deck lid. Here's what I did.

used the 2.0L Porsche runners as these are the only ones to fit the heads and are bigger. I used a bus plenum and clocked it (clockwise) a few degrees by shimming the mounts with washers until the runners lined-up nicely on all 4. I used radiator hose as plenum stub connectors to the runners (this is cheap!!)

Then I used the Porsche 2.0L TB and welded a flange to mount it onto the plenum. Then cut and relocated the arm where the accelerator cable attaches so that it was a pull-type throttle again.

[raygreenwood]

Nice! Hey....did you happen to possibly cc that bus plenum? its the only one I have not cc'd. Its a nice shape. Ray

[j-bro]

Nice! Hey....did you happen to possibly cc that bus plenum? its the only one I have not cc'd. Its a nice shape. Ray

Years ago I cc'd some plenums including 2.0 bus. Off the top of my head, I think it was around 1275cc.

[Piledriver]

Nice! Hey....did you happen to possibly cc that bus plenum? its the only one I have not cc'd. Its a nice shape. Ray

That looks much narrower than the 2.0 Bus plenum I have (off a `78) that's ~same size as 2.1 WBX, give or take.

I used a WBX plenum on mine... made it ~2" wider. Volume is around 1800cc (post mod) using 50mm WBX TB.
(on a 1.8.. with 2L 914 heads, at least temporarily)

Yeah... I finally dragged my butt outside with the camera.
Both are 2.1L WBX plenums. One of these things is no longer like the other...

plenums.JPG