I finally got to drive my 914 again! Back in June I was having fits with the L-Jet system that was on my car so I decided it was time to tackle a project I was wanting to do for some time, a CIS conversion.

I retrofitted a CIS Basic system to my stock 1.8L engine using parts from various VWs and Mercedes and today I fired it up for the first time and was able to take it for a long drive. It felt AWESOME. Smooth reliable power all the way to redline. It has a nice growl to it too. I'm quite impressed. I still have to make some small adjustments but at least now I can get back to driving the car daily and the best part, NO MORE JACKSTANDS! I'm going to drive the snot out of the car this week to get the system dialed in and hopefully next weekend I will take it for a day drive in the mountains. More details and pics to come later.


The cat is happy too!
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I always thought CIS off a VW Rabbit would work nicely. Post lots of details!

Great idea and congratulations. I'll bet a lot of folks will be interested in hearing about what you did.

Were's all the pictures from the build?

Information please!

Zach

Smokey wants more pictures!


Here kitty kitty.

CIS ='CALICO IS SLEEPING' ???

CIS works great on TIV engines.. I had the set up on my Grey shop Bus 10 years ago along with a stroked TIV.. The torque was phenomenal and so was the MPG.. The simplicity of the system is what I appreciated most.

I didn't touch it for 7 solid years.

CIS? Would that be "Cat In Situ"?

The Cap'n, typing with a cat on my shoulder.

you guys are nuts...I don't let the cats on my cars because they scratch the sh$t out of the paint!

Easy to train them. Just wait till they're settled in on the hood and fire it up!

I am working on the same thing except from what Rick suggested, from a Rabbit. Actually, Someone else is working on it (already installed one on his son's Teener) to teach me how to do it. I absolutlely love what he did.

You should see the top on my 1973 911 targa, they love that soft top for sleeping and clawing.

Okay here is a break down of everything I used.

Fuel distributor – VW Rabbit
Warm up Regulator- VW Rabbit
Fuel lines-Audi
Fuel Injectors-Audi
Fuel Pump, Filter, and Accumulator – Mercedes 300 class
And assorted flexible hoses and fittings from various German cars

I used stuff that was readily available at the local junkyard and I spent less than $150 putting this system together. The easiest route though would have been to just get everything off a VW rabbit and be done with it but the junkyard didn't have a complete Rabbit at the time.

The pictures show my initial installation of everything. I’ll clean up some of my workings now that I know the system works to my liking. The airbox/ fuel distributor is simply bolted to the intake runners, the warm up regulator is mounted to the firewall, and the Mercedes fuel pump assembly is mounted on the firewall under the engine.

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Sorry for the crappy pics...

For the injectors I had to fab up some brackets and spacers so that they sit at the correct depth.
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And finally since I was completely new to anything CIS, this book was a great reference!

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Oh and the cat is 18 years old and a HUGE 914 fan

One of these Volvo 240 Aluminum Air Box Tray's would probably fit in there a little better than the Plastic box.

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Yeah I need to do something about that. I had to remove the rain tray just so it would fit. I was thinking about fabbing up a new box. I'll have to look into the Volvo tray though.

Jeffs914/6 was or is installing CIS on his 3.0.

Volvo Intake with Porsche Injection... Click Here

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I was drooling over Dan & Jeff Dixon's CIS setup on Dan's Type IV at WCR and asked for detailed info. Jeff sent me this great site Ferrari400parts.com. The is a lot of documentation there.

Volvo 1800s also used this system and I've found some info by searching for it.

This is definitely something that is in my future since I've got my own 914, my son's 914 and my other son's VW Bus to think about. It certainly looks superior to anything VW/Porsche ever put on a Type IV!

Are there particular years of Rabbits that you want to find for this?

Thanks for all the photos!

whats with the long pipe on the air box?

Why didnt you just put a k&n cone on there instead of the pipe?

Link saved! Thanks! The Rabbit I got my stuff off of was a '77. I chose to go with a K-Jet Basic setup (no electronics/ O2 sensor) but I don't know all the specific years or models it came on.

The pipe goes from the Fuel Distributor/Airbox to the stock 1.8L throttle body. Fresh air gets sucked up from under the airbox.

I would think CIS would also be great as the basic system should do well with minor engine mods ( cam ) and even small displacement changes ( 2056 ) I too am considering this setup. I've had a couple 924's and my dad had several rabbits when I was young. CIS is stupid simple and brilliantly effective

It's "basically" a mass-flow system so displacement and altitude correction are built in, up to the excursion limits on the flapper.

However, like D-jet, it hates intake reversion and needs a mild cam with not a lot of overlap. Pulses in the intake drive the flapper batty...

There has been proof that CIS actually does fine with radical cams....I need to find where that was. I am putting CIS on my tweaked out corvair engine in the bus Already have it in the 914 on the 2.7 (stock).

There's a whole spectrum of meanings to 'radical'... And 'fine' for that matter ;-) Lift is OK, but when you get into lots of overlap there are going to be issues. Are they issues that have workarounds? probably...

Porsche ran CIS on the 934's because the FIA made 'em do it, and they ran just fine, but not with as much power as the Kugelfisher injection they could run in Group 5. They certainly didn't have 'street-car idle' either. I suspect they gave up a lot in fuel economy at idle and part-throttle - but no one much cares about those in a race car.


this being the bus that weighs half as much as my 5,6-liter Titan but gets just as good mileage?

Never did I say it couldn't be made to work. As Scotty says, it's a dirt-simple mechanical injection system, but it does have a few fundamental underlying principles, chief of which is that the instantaneous position of the metering plate is proportional to the fuel requirement at that moment. If the plate is fluttering (and it does have some hydraulic damping to it) that principle isn't true. 6-cylinder engines have pretty much continuous intake flow - 4's are a little choppier by their very nature. And yes, I ran a Techtonics 268º cam in the ur-GTI and it ran great. That was generally accepted as radical as you'd like in an emissions-rated street engine - and I think it might have given the cat a workout if I'd still had one...

Um, the bus comment was separated from the radical cam comment for a reason. They are not related. So, no need to argue The bis was related to the topic of adaptation, the cam remark was related to the concept that there is more cam variability available with CIS than more people think

twasn't an argument. trust me - if I am arguing with you, you will know it ;-)

...
I agree. So you don't need to argue ;-) ...
But it is something to be aware, especially if you're looking for efficiency (i.e. mileage) or need to be concerned about emissions (some do...). Overlap is the killer. I don't recall all the specs for the Techtonics 268º cam, other tha the signature duration. For 911's the sweet spot is somewhere between the '75 'S' cam and the 964 cam.

But the reality is that it's way easier to change cams in a 911 or Rabbit than a T-IV. I just want people to do their homework, think about what they're doing, and make an informed choice. CIS is a thing of beauty in its ability to provide efficient, smooth idle, broad smooth power band, and decent top end - with a minimum of constant tinkering. I used to go from 6000' to sea level twice a year in a 10,3:1 engine with no other attention paid than running premium gas at sea level - which was pretty much necessary only because I ran so much spark advance at altitude.

If you go in thinking you can run any cam you like because the CIS will adapt, you will probably be faced with driveabilty issues. Just look at the changes Porsche made between the last of the carb/MFI cars to the CIS cars. To be sure, a lot of those were driven by emissions requirements, especially in a leaded-gas no-cat environment.

Ok, Jake says it's a good system. He's the man who's done the testing.

Will this system let a 2056 make the kind of power that one with carbs would? What I'm getting at is that I often read a 2056 with D-Jet will be limited to 100-115 hp whereas a carbed motor can make 130.

I like the thought of injection AND the bigger power.

and IMHO yes. But Jake would cetainly know better than I

I have thought about CIS for my 2056, but have held back as I think my cam is too aggressive for it. I'd love to find otherwise.

Zach

Me thinks snot. CIS works on a basic principal. Throttle ( airflow) opens plate , position of plate increases fuel flow via plunger. Therefore the mid range cam you have MAY require a sight adjustment, but would not cause any real issue

Is this hard to integrate with a stock ECU? What are the drawbacks, if any?

I just thought I would post some links that I found helpful before I started down this road...

http://www.shoptalkforums.com/viewtopic.php?t=114309

http://members.rennlist.com/evill/ed1.htm

http://www.thesamba.com/vw/forum/viewtopic...c9d130f4f1aa114

http://www.stits.org/DMCVEGAS%20DMC%20Arch...CIS%20Thing.pdf

http://www.aircooledtech.com/CIS_injection/

http://www.thesamba.com/vw/forum/viewtopic...cis&start=0

I'm not sure how that system would interface with an ECU:

"K-jetronic is a mechanical continuous fuel injection system which does not require any form of drive whatsoever." "K-jetronic: a fuel injection system from Bosch"

Its not simple -- rather mechanically complex, but it is modular and not electronic so in that way it might be simpler to work on:
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Here's a picture of the air flow sensor that controls fuel:
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Here's a diagram describing how it enriches the mix when you stomp on the gas:
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I'm not qualified to comment on how a high duration camshaft might affect the operation of the sensor, but it is clear that strong pulsations in manifold air flow might. I thought that valve overlap acted to mitigate exhaust gas resonance, permitting more fuel to enter the combustion chamber? In the Bosch K-jet material they mention overlap as an important part of their performance/economy/emissions strategy.

I want to know what those who have actually worked on it (K-jet system) feel about the durability of all those the mechanical movements over 25-30 years. Are the necessary components obsolete? Are used parts reliable?

One thing I found very interesting in my research is that later K-jet usedan overlay electronic feedback loop with a lambda sensor.

Thanks to Thinair for providing the informative links.

I can't speak to the overlap limits with CIS (K-jet) but I spent a number of years working 5 days a week on cars with CIS FI.
The system as a whole was relatively trouble free. The common issues were typical of most FI problems, vacuum leaks, injectors wear or get dirty, fuel pumps fail, fuel pump relays fail and of course vacuum leaks.
Also there seemed to be a number of techs that would "adjust" the pressures to improve something (drivability, performance, mileage, etc...), this was usually a huge disaster that cost a lot to fix. Fuel pressures are used throughout the system to control everything and they all have to work together.
Fuel contamination (water/rust or dirt in the fuel) could be a huge problem and required replacement of most components that had fuel going thru them. We had quite a few cases of fuel contamination in the late 70's early 80's but after gas stations started paying some big repair bills there seemed to be a big drop in contamination cases.

It was just a few years ago I sold my last Audi quattro with CIS and it worked fine with an unknown number of miles. It had 190K miles when I bought it and the speedo cable was broke, after I fix the speedo cable I found the odometer only counted miles sometime. I drove it 7 years after that and only replaced a fuel pump relay and an ignition module, well those were the only parts related the engine running at least.

Used parts seem to be available but watch out for dirty parts.

Jim

Thanks Jim, I value your "narrative of experience." I take that the major cans/components are not normally serviceable and the typical cause of failure is contamination of some sort.

My 81 Scirocco, daily driver, has 417,000 miles on it and i have never had a problem with the FI system. I would think that qualifies for dependability.

The later CIS did use a fequency valve (lambda control) system that you can still use. Need to set it to 50 pulses or minimum to negate the 02 sensor but still it would work without the 02.

I had been thinking of doing this also as the system is trouble free and i have access to about 50 of the cars for parts. This thread was just what i needed.


Rex

I have to take that back. I had to replace the Lambda relay a couple of years ago. Damn FI anyway.

Since the system is volume based it is imperative that the engine have an excellent, very steady vacuum signature.

When I was building lots of these CIS engines I designed them like an engine that would run stock FI, but they loved more compression and head work.. Thats something that stock FI doesn't care much for.

It is VERY easy to over do it on the cam side of a CIS based engine, I used split duration and lift on the exhaust side to make my power along with a very mild arrangement on the intake side and was never disappointed.

Jake is your carb cam (the one similar to the 494) too aggressive for CIS?
Zach

Jakes probably under a boxter looking for a oil leak.

VERY cool thread - keep the info coming.
SO many folks jump to carbs instead of dealing with D-jet. If the K-jet system sounds like a great option.

I see the injectors need a custom part, intake routing is custom but simple enough...
throttle body mods?

I used to be a die hard carb die THEN I LEARNED how to work with fuel injection. I have yet to look back. I am currently planning on upgrading the 360 in my CJ-7 to F.I. And considering flipping my dads 1.7 over to CIS if I ever get the metal work finished

Maybe one could get some stainless lines made up from Chris Foley ( Tangerine Racing ) to run the pump up front and have lines that would take the pressure for this. A fella on evilbay sells stainless lines for the Mk1 Rabbit with the bubble flair on them for Rabbit replacement , Chris might be able to do this as he's familar with 914s.

Jack

curious?

if one were to use a megajolt jr with edis parts and mcmarks crank position sensor for ignition only ...

http://www.914world.com/bbs2/index.php?showtopic=97550

could cis be used with it - versus carbs?

or does cis tie ignition to fuel some how?

jim

I've followed this thread hoping to find relief from the oppression of the MAPS, a part that is, in my limited experience, too fragile, too hard to find, and too critical to operation of the d-jet system for my comfort. Under that criteria, and given the fact that I don't have a super-sized motor to fuel, I don't think of k-jet as a viable alternative to my imperfectly stock FI.

The OP, jcl914, and Rex-n-effect are obviously talented mechanics and/or have identified a supply of spare parts. They put their talents and resources to good and productive use. I'm very grateful they shared their interesting information about CIS

but...

I've been checking pull-a-part inventories for three cities for the past two weeks for a 1977-79, Rabbit, Dasher, Jetta, or Scirocco and have only found one (later models had the lambda circuit and an ECU).

Assuming I found a donor with its fuel system intact, after the conversion I'd be in the same position as I am now with d-jet. No, the critical k-jet components are not obsolete, just insanely expensive (mass airflow sensor/fuel distributor = $1800 at Rockauto). I didn't check the e-bay but with that new price as a point of departure, used k-jet parts are probably just as pricey as d-jet parts. At (new) $200 for an accumulator $75 for an idle air regulator, $200 for a high pressure pump, and $50 for Bosch injectors, repair costs could be prohibitive.

I don't know where a stash of late 70's VW' donor's are anymore than I know where a supply of early 70's 914's are. so tracking down a solid ECU MPS, TPS, CHT, and dizzy fuel points for my stock motor doesn't feel different that tracking down a fuel accumulator, mass air flow sensor and fuel distributor, idle air valve, and special injectors. Maybe easier since the stock components have fewer moving parts?

Now if you went the next step and converted to K-L - jet ('81 Scirocco's were really neat cars, BTW) with an O2sensor and a lambda control circuit, that might be a different and even more interesting story...

Don't know nothing about it except what read; however, fuel delivery is continuous. ("K" means "Konstant") There are no injector distributor points. I have to believe it doesn't make any difference how you fire it.

You are probably correct that piecing together a system from bits you pick up off seperate cars would be too difficult for most, I would not want to try. You would indeed want to find a complete or mostly complete system from a single source. How possible is that anymore? I don't know.
Often I think of things as they were for me when I was working in the shop everyday. Well I have been working in an office for 16 years now and I don't come accross too many CIS parts here but we do have a huge library of factory manuals to go thru.
VW & Audi used CIS or CIS w/lambda up thru 1983 and a lambda system would only add a little extra to the installation.
The key components that need to be matched to each other are the air flow sensor and fuel distributor. The injectors and comtrol pressure regulator should be close matches and you could use many different CIS fuel pumps, accumulators, aux air regulators. You would still be faced with patching together a system that you won't know for sure how it will work until you are done and you will likely have to do some teaking to get the mixture correct accorss the board.
It can be done and has been but I Would consider it an experimental project rather than a cheaper solution to D-jet.
An L-jet system on a D-jet engine work pretty good and the earlest L-jets were newer technology than the oldest D-jets.
I put a 1.7L long block in a 74 1.8 914 using the 1.8 L-jet system and it ran better that any 1.8 car I ever drove. The L-jet system really like the extra compression the 1.7 had.

Jim