Finally driving again!, Type IV CIS conversion Options

[Jake Raby]

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.

[VaccaRabite]

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

[charliew]

Jakes probably under a boxter looking for a oil leak.

[Chris Pincetich]

Jakes probably under a boxter looking for a oil leak.

(IMG:style_emoticons/default/av-943.gif) (IMG:style_emoticons/default/shades.gif)

VERY cool thread - keep the info coming. (IMG:style_emoticons/default/beerchug.gif)
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?

[scotty b]

Jakes probably under a boxter looking for a oil leak.

(IMG:style_emoticons/default/av-943.gif) (IMG:style_emoticons/default/shades.gif)

VERY cool thread - keep the info coming. (IMG:style_emoticons/default/beerchug.gif)
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?

(IMG:style_emoticons/default/agree.gif) 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 (IMG:style_emoticons/default/dry.gif)

[jaxdream]

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

[jimkelly]

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

[Prospectfarms]

(IMG:style_emoticons/default/confused24.gif)

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...

[Prospectfarms]

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

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.

[jcd914]

(IMG:style_emoticons/default/confused24.gif)

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...

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

[jcd914]

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

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.

Correct CIS does not care about your ignition. Some used a fuel pump relay that would not stay on without an ignition signal but that is it.

Jim

[jaxdream]

This mod would be a great alternative to buying a complete carb setup , if one didn't have a fuel induction system to begin with. If you already have a fac. FI setup , then it is probably the best way to go , although the critical parts are getting harder and $$$ to source. The CIS was used on a lot of different cars and is still more plentiful .I checked over eBay for a current price check gauge and the hard parts didn't seem any more expensive than what it would take to piece together a d-jet or l- jet setup from scratch. There seems to be alot of fellas that have had good experiences with the CIS a very good gauge of reliability of the system. It's not modern FI by a long shot just another way to get air and fuel to the cylinders. I like what I have read about it and probably will in the future ( when the engine side of my project gets there ) dig into this mod for my induction needs , as what I have at present , carbs that may be junk , this setup would be very doable .
My $.02 and I hope my posting doen't kill the thread .

Jack

[Prospectfarms]

jcd914 wrote: "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."

You are the third person I've heard say something positive about l-jet on a 1.7. One was a member here, who referenced to me a thread from several years ago. The other was a local guy who I met the other day. I'll look for some more threads on that topic. If there's some information I'll report back in a new topic. Sorry for going off-post.

(IMG:style_emoticons/default/confused24.gif)

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...

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

[nein14]

I can speak of it's reliability and performance, I currently have owned the Evil Ed 914 GT Turbo for the past 7 years. I was building a clone of Ed's car when he put his car up for sale and I bought it.

the CIS system that I got from Gary Miller that Ed used I recently sold to a friend who recently installed it in his 914 2.0 with grest success!

I have tweaked the CIS in my GT Turbo with the injectors fro a 6.9 liter V 8 Mercedes which has provided increased fuel flow as well as 20 degree lower cylinder temps, also changed the WUR to the one used on the 930.

The CIS components are avaliable and as far as the intake runners if you find a set out of a VW bus that accept the CIS injectors you don't have to mod the 914 runners they bolt right up.

[dlee6204]

A little update on this….

The car is running great! I had some trouble getting the fuel mixture set correctly (long story but I shouldn’t have messed with the mixture in the first place) but I got through it and have been driving the car the past few days. Everything is running smoothly and even in extreme heat the car runs fantastic. I filled up the tank tonight and will be doing some mileage tests to see what kind of numbers I’m getting. I’ll report back. (IMG:style_emoticons/default/biggrin.gif)

[jaxdream]

Great (IMG:style_emoticons/default/piratenanner.gif) , I was wanting to see an update on this mod. Keep the info coming please.

Jack

[pete-stevers]

great thread!!

[rohar]

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

After years of working CIS on other engines, I suspect it is. If the cam gets too agressive, the air lever in the fuel dizzy starts to move erratically. In theory, this can be abated by adding anti revision geometry to the intake track, but I've never tried it/seen it. I've only read about it from some of the ancient notes from Drake Engineering. That said, as you increase air velocity, cam becomes less and less important. I've run rabbit 8v engines well over 200hp on CIS. In that environment we could get away with cams that simply wouldn't work at lower air flow.

I've seen CIS come up a lot lately, is there something in the air? Anyone ever thought of going digifant? Digifant I lends itself easily to an engine like the type iv.

[rohar]

...
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...

I've not had the problem tracking down used CIS parts in the NW like you're seeing. I can drive about 2 miles and score a whole system.

By phone, you might want to give Campbell Nelson a call in Edmonds, Spaldings or Whitey's Wrecking in Spokane. There's probably more, but those three have been good for me over the years.

BTW, I was buying K-Jet dizzys for $150 new 10 years ago. Given what they're selling for today, I shoulda bought more off them (IMG:style_emoticons/default/sad.gif)

[rohar]

After sleeping on it, I could be convinced to go out and pull full systems and bench test them if the money's right. Might take me a little time as I'm packing right now for the move, but it's an idea.