Planning bolting Holley on 2.4T

[Zendalar]

Yes, this friend of mine suggested me bolting a Holley electronic injection system on my 2.4T. It is a very simple design and can be bolted on V8 and V6 engines so why not on a Porsche? Friend of mine told me he had carbs earlier and of course like every carbs they have "dead spots" somewhere along the revolution range. This holley had changed it all, car is running very smooth now and its also very responsive (fast) to throttle.

The Holley has an external "computer" that has adjustments for idle, middle, and full throttle positions. Also it has adjustable fuel pressure. This electronic injection is meant for "every" car and so the car does not need to be certain brand like General Motors.

I will build the intake manifolds myself.

What are your opinions on this matter? Should I give it a go?

[dwil]

I think this sounds like a good idea
(posted on cis to efi conversions topic
earlier) Somebody has surely tried this!

[john walker's workshop]

do it. nothing ventured, nothing gained.
even a single holley CARB would be interesting.

[911pcars]

Zendalar ,
Too many people are satisfied with the status quo. I like your inventive spirit. Go for it and let us know.

Sherwood Lee
http://members.rennlist.org/911pcars

[rvanderpyl]

Which Holley System? What is the cost and dos it have an ignition module??


Robert

[Oldporsche]

Why not modify an MFI unit. Just install digital injectors where the mechanical ones are.

This is a doable project.

Good luck,
David Duffield

[RarlyL8]

If I am thinking of the same system, the Holley Pro Jection, is isn't EFI but TBI.
This is a wet system requiring equal length intake manifold runners to prevent a possible lean condition in any one cylinder.
I started a project some time back to put a Holly 4bbl (390cfm) on a 3.0L SC. Shelved the project when it became obvious that equal length runners would take more time to build than I wished to invest (stock CIS runners are not equal length). Also, because the system is wet, the main plenum that the carb or throttle body sits on must be able to withstand constant fuel contact.
You probably knew this all ready, thought I'd mention my findings just the same.

[Zendalar]

No, this holley is the general type and does not come with ignition unit. It does have only one sensor (well, 2 actually) that is the sensor for "fuel enrichment" when engine is cold. Another one is the "sensor" you have to attach for the revolution meter points, or would I say, directly to the distributor.

I was planning on TBI also, but its a bit more complicated. This holley I am planning is known for its inability to spread fuel "evenly" on all cylinders (too lean/rich) because its designed to be attached to "one throat" intake manifold. TBI would inject gasoline directly to each cylinder. These units are a bit costy, but I can get one used (full set) for 600$.

[RarlyL8]

Throttle Body Injection (TBI) is the single throat carb style unit.
Tune Port Injection (TPI) has an injector for each manifold runner.
My earlier post was referring to the carb style TBI unit.
What materials are you planning to use for the plenum? My initial thoughts were aluminum, but there are now composite materials available that can do the job as well.
Several years ago (OK, many years ago) the aftermarket had an adapted system out to place a single 4bbl carb on a Corvair engine. If you can find one of these units you would be ahead in the fabrication. The intake runners numbered only four due to the engine having siamese ports on each bank. The plenum is what you need, so the runners could be discarded.

[clevy70911T]

Zendalar, Please keep us informed on your project as I too would like a more "drivable" and reliable fuel system in place of my Zeniths. This is very interesting as I had thoughts of this with my first 911 and it's carbs were toast. Bought PMO instead. Thanks
clevytr6@home.com

[Wrecked944]

Sounds like a great idea. Have you seen the parallel "CIS to EFI" thread? Some of the folks on that thread have considerable experience in this area. Does Holley have a website where we can see the specs on the system?


------------------
Janus Cole
1980 911SC & 1987 944

[Zendalar]

Dunno about website, but I am planning to do this, so I will keep you posted.

//Zen

[stlrj]

Here's how it might look if you used a 2.7 airbox and manifolds.


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