MFI throttle bodies and turbo injector blocks

[Alan Cottrill]

assuming that turbo injector blocks can be modified to accept EFI injectors...(I think it can be done).

is there any reason you couldn't run an MFI intake system on top of these blocks?

you'd just need longer studs...right?

that way you could have individual runners and EFI at a much lower price than the commercially available throttle bodies on the market.

i know there are other hurdles to jump like TPS, MAP, and air temp. but those can be jumped.

[Grady Clay]

Alan,

I don’t see any reason why not.
Huge advantages and in the best Porsche tradition.

Best,
Grady

[cowtown]

What's the port size of the MFI system?

[Alan Cottrill]

I don't know. I don't actually have a set of mfi throttle bodies yet. I've never even seen a mfi system in person. i was just thinking of ways to get around $2500 for throttle bodies.

[dean]

I think you might have a problem machining the stock 930 injector blocks. They are a really hard plastic material. They do sell Alu. blocks though.

[911pcars]

You could also just use carb bodies and a jet holder underneath. Strip the carbs of secondary venturis, floats, jets, accel. pump, etc. It doesn't look as sexy as a dedicated throttle body but then again, you're not buying a $2000+ throttle body setup.

Anybody have a pic of this conversion?

Sherwood

[KobaltBlau]

I like your line of thinking! I was thinking about compromising by using a carrera 3.2 manifold on a smaller engine, but it ain't the same! I'll be curious to see what you find out.

Andy

[304065]

MFI throttle bodies will curve your spine, cause your car to rust, cause all the hair to fall out of your domestic pets and turn every other tooth brown. I'd leave them for the T, E, S and RS crowd to use to keep their cars alive!

[Matt Smith]

John, you're right.
There is also the problem of oil dilution from petrol- and the fact that there is nowhere to mount the mfi pump belt spells mayhem in my eyes. This idea is mindless lunacy.

[RarlyL8]

I did this a couple of years ago.
You don't need to use the turbo injector blocks. MFI throttle bodies can be modified to accept EFI injectors. The only problem that was a show stopper (for me) was the size of the MFI stacks. I had access to several sets, all too small. The only set that came close was from a racing engine - very high $$$. So I chucked the idea. I gave my complete 2.4T MFI setup away to a fellow Pelicanhead so I have no pix to point things out.

[Tyson Schmidt]

The throttle plates are 38mm. The openings can be opened up to this diameter.

keep in mind that 6 38mm throttleplates will probably yield more performace than the one big throttle plate that comes on CIS or DME. And the magnesium stacks can be bored out.

Even though the MFI throttle bodies are 38mm, which are smaller that 40 or 46 Webers, the MFI intakes don't suffer from venturis or pre-atomizers blocking the intake path.

One more thing. You could buy a set of T or E throttle bodies, and have them enlarged by Eurometrix for far less total investment than a set of TWM's.

Oh crap, I'm supposed to steer people away from this stuff! I'm a terrible MFIWDP operative!

[thethrill]

Why recreate the wheel? A cost effective performance EFI set up with induvidual throttle bodies is the TWM 3003 series manifolds. They mount on Weber/PMO manifolds. The TB's are less than $1,200 for the pair and the PMO manifolds with linkage etc. is approx. $400. They come with throttle plates sizes of 40, 44, 46 and 48 mm. So they will work witha 2.0 to 3.6 motor! Get the vintage look and feel with EFI performance and tunability! Add a coolant, TPS and map sensor, a fuel pressure regulator, wiring harness and ECU and there you go! This is not rocket science.

It works great! I have this set up on my daily driver 3.2 w/big cams ported heads etc.

[KobaltBlau]

Originally posted by RarlyL8
I did this a couple of years ago.
You don't need to use the turbo injector blocks. MFI throttle bodies can be modified to accept EFI injectors.

Exactly how, Rarly?

[jluetjen]

Did anyone ever try just drilling and tapping some old weber carb bodies to convert them into throttle bodies. You get to ditch the venturis, jetting and stuff and just keep the bodies and the throttles.

[RarlyL8]

I played with a set of junk Webers as well. If you strip them bare and cap all the holes they may work. By the time you get the machine work done, rebuild the plate bushings, and fiddle with everything to make it work you're probably better off with the $1200 units posted above. They are sharp and probably flow better.
The same logic killed the MFI deal. I picked up a set of junk injectors and machined out the small stock injector ports. Then I made adapters, then needed fuel rail mods and various bracketry. You get the picture. A true machinist could do this right for small bucks. Not so simple or cheap for the regular backyard mechanic.

[KobaltBlau]

Thanks for the response, RarlyL8. makes sense to me ....