Finally driving again!, Type IV CIS conversion Options

[dlee6204]

I finally got to drive my 914 again! (IMG:style_emoticons/default/mueba.gif) (IMG:style_emoticons/default/biggrin.gif) 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. (IMG:style_emoticons/default/evilgrin.gif) 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. (IMG:style_emoticons/default/driving.gif) More details and pics to come later.


The cat is happy too!

[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...

[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

[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