I have a 914/6 conversion with a 3.0l SC engine. I have installed PMO 46mm carbs and considering switching to fuel injection. I would prefer to use stock fuel injection. Has anyone had success installing 3.2l engine Fuel injection components on a 3.0 engine?

I have only seen stock CIS injection on a 3.0 914-6 conversion.
I would also post in the Pelican 911 technical forum.
https://forums.pelicanparts.com/porsche-911-technical-forum/
I have seen some threads over there on the topic of using 3.2 DME injection in place of CIS injection

Quite a few done on pelican.

Search - motronic injection

I did a SC 3.0 with 3.2 manifold and aftermarket programmable FI many years ago (20+). Pretty easy to do. The whole system is still installed and working on my friends car.

john

If your PMOs are 40s send me a pm .. I might be interested
sorry... I just read 46s

Sounds like a good option, but be aware the prices on 3.2 intake manifolds are pretty high. I was thinking about something similar on my 2.7 build, but the price was too high for my budget.

Let me ask this. Will the stock 3.0 fuel injection components work on a motor that has JE pistons(10:1) and aggressive webcam cams or will it require a custom fuel/air map, therefore an aftermarket FI setup

Custom chip for the stock ecu.

Great thanks. How do you map the programming for the Air/fuel on the chip? Are there people out there that can do that?

It is my understanding that the CIS can take more compression
but it is not great with much more cam..
I think 964 type cams will work and add a modest amount of power
but I think the timing is critical..

You mean stock 3.2 intake right?

It should, check with Steve Wong at 911chips he can do a custom chip for the 3.2 intake and ecu. I think they used to have a bigger TB too.

The cis will not be able to accept your cams
Too aggressive

Use the stock CIS intake and throttle body. Put EFI on it.

Here is a link to the kit to do it.

https://www.bitzracing.com/products/Partial_EFI_KIT/



This is designed to replace the CIS on a 911 with EFI. It should be easy to find the CIS intake hard parts.


Hope this helps.

Clay

Would that setup work with a 3.2 manifold? Seems like it would work with any manifold?

If so, would I use the stock 3.2 throttle body?

Yes, it would work with the 3.2 manifold. But they are harder to find, and CIS heads may need an adapter to work with the 3.2 manifold. I am not 100% sure on that though.

Plus... the CIS manifolds, plenum, and throttle body are readily available and cheaper than the 3.2 motronic manifolds.

Clay

I was planning on running a 3.2 EFI on my brothers 3.0 but went with the Weber 40ida instead. One reason was it looks period correct. Yeah carbs can be a pain to tune and keep in tune. Here's the deal with the Carrera intake install. You will need manifold to head adapters. Turbo craft sells them for around $275 for the set. If you can get your hands on a good used intake more then likely you will need to replace some of the injection lines. Look up the prices they are nuts. The injectors you'll need depends on the engine combo. New efi pump and lines to and from tank. Don't forget the sensors you need to install to make it all work. Depending on your trans a mod to the bell housing for the sensors. Engine management is another thing. You can run the stock motronic and have a custom chip made or get another system. Either way it's not cheap and I'm sure I'm forgetting a few other misc things that need to be done. So you get my drift why we went with the Webers yet? Look at spending well over 3 grand on the low end to make it all work. The kit that Clay posted maybe your best bet if you want to get away from the carbs. Depending on your head ports you'll need either small or large port manifolds for the cis. My brother's 3.0 seams to be similar to your combo but he's running 40ida Webers. I drove the car and seamed to perform well. I was doing 2nd gear burn outs without a problem. Now his dizzy isn't re-curved yet either so I'm sure there's a few horses left there.

Why are you running 46's? I feel the 40's work well on my brothers 3.0 .
You happen to know your head port size?

Maybe it would be easier to just trade my 46s for 40s, would be easier replacement.

Anyone want to trade?

Before you start trading. Why are you wanting to get away from the 46's?
What's your engine combo with head port size? 40's maybe your best bet but answer these questions 1st.

This engine has been in my wife’s 911 for a number of years..
It was initially built to increase HP and still be able to pass California Emissions.
It was built by Ralph Meaneys engine builder in Massachusetts back in the day and
lived in California for a number of years. It is back in Massachusetts now and still runs well.. For what it is worth…???

Click to view attachment

Love the twin plug!

How easy is it to get a cap and rotor set for it?

Clay

I don’t know why everyone says the 3.2 manifolds are expensive or hard to get. I’ve sold plenty for $500 and a wtb on pelican will get you a pair.

That may be true.. but using the CIS intake means not having to purchase the intake adapters to make the 3.2 intake work with CIS heads. That saves $275.00.





Clay

The problem is getting everything else to go with the manifold. Most fuel lines are shot by now. New replacement fuel lines will cost you around $650. I don't care either way if one wants to use a 3.2 intake. Just making them aware of the hidden cost that follows.
I went down that road and it turned out to be too expensive. I ended up selling my manifold in 2017 for $900..

As for the op lmk your engine setup. I can look up the jetting I used in my brothers carbs if that helps you.

I will admit.. I am biased. I hate carburetors. Not just a little bit, but a LOT.

The funny part is that the factory six we have has Webers on it. So I have to maintain them.

I prefer an EFI system over carbs any day. Easier cold start, easier to drive, and much easier to maintain.

Go up and down a mountain without having to stop halfway up and halfway down to change jets. No fuel smell in the garage from bowl vents. No having to pump the accelerator to get enough fuel to make the car start.

There is a reason no new cars are built with carburetors. Same reason we don't use external band drum brakes or wooden wheels anymore. Obsolete tech.


Clay

It is a 3.0l with JE Pistons (10:1), webcam 502/104 grind. The heads have the larger intake size(can't remember the exact size). Then the 46 PMOs.

Again, when driving under 3k RPM it tends to sputter but once 3K hits it is fine

I am with Clay I hate carbs as well. Your problem sound like a tuning issue. If you decide to go with fuel injection couple things.
The adapters that have been mentioned are for running a 3.2 manifold on a Turbo motor with stock small 32mm inkakes . The intake on the 3.0 big port and 3.2 head are almost the same. 3.0 39mm 3.2 41mm and adaptors are not required.

3.2 head

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big port 3.0

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The indent for the fuel injector is a slightly different shape between 3.0 and 3.2. I gasket matched the 3.0 head to the 3.2 gasket with a dremel and bolted the intake directly to the head.
The main difference between 3.0 and 3.2 is the intake port height is different between a 3.0 and 3.2 head (beside port size) is the 3.2 is shorter and there is a thick (about 1/4" thick) gasket that goes between the manifold and head in stock application.

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To use the complete 3.2 fuel injection system on a 3.0 is difficult. It would require complete rebuild of the motor, head machining for Temp sensor and 3.2 flywheel. The distributor on the 3.2 rotates the opposite direction of the 3.0 and would require changing the gear on the crank to use 3.2 distributor on 3.0. The 3.2 distributor does not have any trigger or advance mechanisms as the advance is controlled by the ECU and the trigger is from a sensor that reads the teeth on the 3.2 flywheel to provide speed and possition information to the ECU. Temperature sensor screws into 3.2 cylinder head.
It is much easier to use a aftermarket ECU. You can feed engine RPM information to the aftermarket system from the trigger wheel in the SC distributor (or use tach signal).
In my conversion I used the factory 3.2 manifold, throttle body (modified to include Throttle position sensor), fuel rails, injectors and lines.
ECU was aftermarket. Had to add the TPS, Map sensor, intake air sensor, O2 sensor and Engine temp sensor, these were all GM parts on my conversion. I used the SC idle air bybass for fast cold idle.

If you still have the SC intake the blitz system is a pretty complete kit for conversion to EFI.

john

My brother has the same p/c's, webcam 120/104 , heads are 3.0 euro/big port (39 mm intake/35 mm exh) , and Weber 40 ida. Carbs are setup as follows :

36mm venturi
short aux venturi
155 mains
F3 emulsion tubes
170 main air correction jets
60 idle fuel jets
50 accelerator squirter jets

It's been a while but pretty sure this was what Paul at Performance Oriented recommended. You maybe able to re jet your 46's but not 100% if that'll work.
I believe Paul has retired from the carb business but try over on Pelican site as he may answer. His user name there is 1QuickS .

I have a 3.0 case and crank but I’m going to use 3.2 p&c’s and 3.2 heads to make a 3.2 short stroke. Not sure on induction yet. Maybe a 3.2 intake with VEMS engine management.

3.2 tip - you can get your fuel lines rebuilt for about $250.

short stoke 3.2 means 98mm pistons and bored out 95mm cylinders and the 70.4mm crankshaft. been thinking about this same build. Jim