CIS on a 914/6

red-beard · red-beard's Garage

Has anyone tried this? Experiences?

James

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Wayne did. He has some notes and pics about it elsewhere on this website. His was a 2.7 with CIS (because his 914 is a 74, so the engine needs to be a 74+ which means CIS unless you go to a 3.2+). He did not have to cut the rear trunk wall.

Others I've seen have needed to cut the wall. I think Wayne got a bit more creative with mounting the fuel distributor and intake boot.

MikeZ who sometimes stops by here did the CIS 3.0 motor in his 914. He did cut the trunk wall.

I've seen others.

--DD

red-beard · red-beard's Garage

If the MSD unit doesn't help...I'm going to try to install CIS.

No, I'm _NOT_ selling the carbs...

Dave, do you all have a used or rebuilt CIS fuel pump?

James

J P Stein · 07-23-2002, 09:35 AM

Do some research BEFORE you start spending any money.

If you insist on doing this, you'd be better off with a motor made for CIS. The heads on your 2.0 are a show stopper. Everything else *could* (I think) be dealt with.

It takes some time and patience to learn to deal with Webers.
This assumes that they are in good working order to start out with.

If you were to take the car to someone like Otto's, they WOULD make it right and prolly let you look over their shoulder while doing so.

red-beard · red-beard's Garage

I was planning on buying an engine and rebuilding it and putting the CIS on, then installing it, carefully storing the original engine....Gotta keep those numbers straight.

Atually, it looks like I should go MFI, if I do this....

James

GregS · 07-23-2002, 11:29 AM

James. I noticed your reference to MFI and thought I'd offer up a couple of thoughts. I have no expertise with it, but have asked a couple of questions and here's what I've learned. I'm not sure of what p's & c's/cams you will be running or whether you've got an MFI system yet. If not, a pump, throttle bodies, etc., can prob ably be had for around $200. I have talked with Gus, at Pacific Fuel Injection, about pump rebuilding costs and you can figure somewhere in the area of $1000 to have the pump rebuilt and space cam matched to your engine configuration. I also spoke with the folks at Eurometrix about the costs involved with machine work on the intakes, and depending on your engine configuration, you figure anywhere from about $500 to $900. All told, I think I figured somewhere around $2600 or so for a complete (read: nearly new) MFI install for a 2.7RS clone, based on starting with an MFI system for a 911T. Again, based on my very limited understanding of the system, the most critical phase of an MFI conversion is the initial installation and setup. If that's done correctly, I've been told they are pretty reliable. I've also heard that there's nothing quite like the sound of MFI at WOT! If you have additional information, I would sure appreciate hearing more from you. If not, I hope the above is helpful to you. Greg.

rdvnac · rdvnac's Garage

Actually, Mike Z currently has a CIS euro 3.0 for sale elsewhere on this site (I'll take that C-note now, Mikey).

I thought Clay P. from rennlist was doing an MFI 914-6 motor, but in a quick check I didn't notice any particulars on his site: http://www.perrinefamily.org/project914-6.htm

I really feel your pain on the Webers, hope you can get 'em sorted out. Mine have been really excellent once dialed in (by my mechanic, not me--I was great at dialing them *out.*).

If you want me to send you my "Weber Carb Tips" file, miscellaneous info I clipped from many different sources, let me know.

red-beard · red-beard's Garage

I'll take any help, short of a gun. Several people have tried to steer me away from CIS, but reading through Miller Fuel Injection site, it seems like it should be a no brainer on the 914/6. Maybe a little modification to get it to fit.

This weekend, I plan to work on the carbs. New Gaskets for the driver side, already have done the passenger side. Then next will be changing the idle jets.

James

campbellcj · 07-23-2002, 09:42 PM

I'm an MFI fan too, but changing from Webers to MFI on a 914/6 to circumnavigate a carb difficulty seems like a kinda odd approach to me. Besides coming up with an MFI setup that is 'correct' for a 2.0 911T (which was never made, AFAIK, so Gus would have to modify something), you would also have to change cams so you'd have the pump drive. And you'd have to figure out/fabricate the pump preheat and starter solenoid systems. All told, probably up around the cost of a brand spankin' new set of PMO's, or a "modern" EFI system like the Electromotive TEC-III or similar.

It could seriously be cheaper to buy an entire 2.2-2.4 MFI engine to drop in

Then again, like JP says, you could probably just bite the bullet and get your Webers straightened out for something between a sixer of good German beer and a couple of c-notes...

Just my $.02

jabb · 07-24-2002, 02:15 PM

If you have an original 914/6 motor that you want to put CIS
on you will have issues with the Heads Cams and Pistons....

All very different for CIS...... or maybe I miss understood what you are trying to do.....

thesey914 · 01-15-2003, 11:00 PM

Does anyone have a link for pictures or details of how to fit the K-jet (cis) with out cutting the rear trunk?
I've searched the entire PP sit for details of Wayne's but haven't found anything.

Clay Perrine · 01-16-2003, 04:23 AM

I have done lots of work on CIS systems in the past. It is a very good system, but not tolerant of radical cams. If you want to use CIS, use the whole 911 CIS engine. The heads, pistons, and cam profiles are very different for a CIS motor. Also, be very careful, and DO NOT use the factory fuel lines with CIS. The fuel pressure is Much higher with it.

As for MFI, Porsche actually intended to put it on a 914/6 if the production had kept going. I have found some parts that show this was the case. I have a set of factory, unmodified heat exchangers that have the heater tube for the MFI injection. That brings up another note. If you decide to go with MFI, you will need to get a set of heat exchangers, as MFI uses the heat from it to change the mixture after warmup. You will also need to modify the engine tin to allow space for the injection pump drive belt. I have the engine tin modifed for mine, and I will be taking pictures as I get to that stage of the project.

For what it's worth, the MFI will get you more horsepower.

Hope that helps.

Mike914six · 01-16-2003, 04:52 AM

I have a 2.5 l (short stroke, big bore) in my 914 w/MFI. I makes some of the best sounds. I like to just set in it and blip the throttles. Nothing like an MFI Porsche motor howling away a foot behind your head.

Jim Smolka · 01-16-2003, 05:02 AM

The first 6 cyl motor I installed was a 3.0 CIS motor. Fortunately, the CIS motor had a Stainless Steel Air box. The SS was a little lower, therefore, no need to cut the trunk. However, I needed to move the engine latch assy to the passenger side.

Things you will need depending on which year CIS system you have.

1. Air boot with out openings in the that point toward the trunk wall.

2. Adjustments to the fuel lines (bending lines, different connections [Wayne has pictures])

3. Modification to the engine throttle assy. (not a big deal, a little grinding here and moving the pivot point to the other side)

4. Fuel line connectors (strange metric to ???).

5. Fuel Accumulator / fuel filter bracket.

6. Fuel Accumulator and Fuel Filter

Number 4 is not easy to do. The fittings are European and fuel in and fuel out lines are difficult to match.

IMHO, a 3.2 DME system is much easier to install. Plus the DME system operates better.

It is possible to install a 3.2 DME system onto a hot 3.0 engine

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Anything is possible, with enough time and money. If you use an aftermarket ECU (and quite probably aftermarket sensors as well), then the 3.2 manifolding and other "hard parts" are an easy way to go.

I'm not at all sure that the stock 3.2 Motronic system will work if just bolted up to a 3.0 motor. (Even assuming you get the flywheel sensor stuff dealt with and so on!)

Hmmm.... I can't find Wayne's write-up with pics of his CIS setup. I'll have to check around for it later.

--DD

thesey914 · 01-17-2003, 04:23 PM

*Bump*
Hey Dave, did you have any luck finding Waynes article?

Mountain914 · 04:23 PM

I've got an 82 3.0L w/CIS in a 72 914, and no cutting involved.
You loose your engine cover latch is about all. I'm very happy with it. I have an access-panel to make belts, adjustments much easier.

morgan_harwell · 01-20-2003, 08:02 AM

I installed a 1973 911T 2.4L CIS FI engine in my 914/4 back in 1987. I did it originally for smog reasons. Every time I drive it, and I drive it alot*, I'm so pleased with the engine choice. It was a fun car prior to the engine swap, now it's a Great Fun Reliable car!

I did not have to cut the body. I did move the engine lid latch to the passenger side of the engine bay to clear the fuel distributor (the engine lid & bay are designed for this). I fabbed a right angle fuel fitting, to replace the stocker on the back of the fuel distributer, to clear the rear firewall.

The 911T 2.4L CIS FI engine is SWEET!
Compared to the carbed 2.0L 4 cylinder it replaced it gets better gas milage*, has 50 more HP(140) and passes smog easily. The engine now has 248K miles on it and running strong. I doubt carbed engines live this long between rebuilds. We also have a 911sc with a 3.0L CIS engine. That car now has 269K miles on its original engine (heads have never been off it).

The CIS FI systems on both cars have been mostly trouble free. Work has included replacing manifold boots, injectors, 1 cold start injector, 1 warm-up regulator. After all these miles I can't complain.

If CIS engines have a draw back, it's that they don't like sitting around unused for long periods of time. The fuel injection system needs fresh clean fuel. Fuel gone bad will clog things up and corrode parts. CIS engines may not be a good choice for Garage Queens.

--Moe--

*It's my daily driver, except on rainy days.
*21 vs 19 mpg city, both engines 35-37 mpg hwy.

Dave at Pelican Parts · Dave at Pelican Parts's Garage

I talked to Wayne, and he cannot find his write-up at the moment either.

GregD · GregD's Garage

I just got the 2.7L CIS in my car. Everything is working, but the throttle linkage is wierd. Gas pedal movement from idle to WOT is very short. So short, it's hard to drive. I noticed in the picture above that part of the stock linkage has been removed. What's the trick setup for this?

Jim Smolka above listed :

3. Modification to the engine throttle assy. (not a big deal, a little grinding here and moving the pivot point to the other side)

What all needs to be done for this?

Greg DeBord