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Low cost fuel injection
Posted by: cnicol ()
Date: May 16, 2008 08:21PM

Tom said:
..well,here's the spare VW fuel distributor and airbox..the engine in the 84 Scirroco is complete,with the whole system-including fuelpump/accumulator..move along,,nothing 'electric' here...

Tom Z

Craig replies:

The K-Jetronic w/O2 is an excellent and easily adapted fuel injection system for a Corvair. I think the Scirocco was rated at 113 net hp and should map well the the Corvair engine requirement. The airflow meter/fuel distributor has four injectors that could be mounted in a 4-bbl manifold, with the fuel distributor where the 4bbl was supposed to go. I other words NO ENGINE MODIFICATIONS. IMO, this is the holy grail for simple Corvair FI and it's even adjustable!

This is it for simple, low cost FI and the O2 version will self tune.
Craig
P.S. I can't beleive how corroded things get back east! I guess I'm spoiled.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
66 Red Monza 2dr 140/4 EFI 60k
61 Seamist Jade Rampside 140 PG
65 Cypress Green Monza 140/4 4dr
65 White 4-dr 110/AC/PG (parts)



19 Tons of parts in boxes




Edited 1 time(s). Last edit at 05/16/2008 08:22PM by cnicol.

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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 16, 2008 08:48PM

Oops - forgot the picture of the rusty remains that got Tom Z and me thinkin' about this hardware.
Craig

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Re: Low cost fuel injection
Posted by: lgoodwin ()
Date: May 16, 2008 10:17PM

Uh, how do you adapt F.I. for a 4-cylinder application to a 6-cylinder motor?

1962 Corvair 900 sedan1967 Corvair Monza 140/4-speed1968 Corvair 500 coupe1983 Mexican Mustang 5.0
1962 900 sedan needs a home1967 Monza 140/4-spd1968 500 coupe (now my son's)1983 Mexican Mustang 5.0

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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 16, 2008 10:42PM

The K-jetronic is just a fuel sprayer. It's not sequential. Fuel flow is proportional to air flow and the airflow meter is integrated with the fuel distributor. The 02 sensor versions ('81-up) have a simpler airflow meter and use the O2 for fine tuning.

For a simple installation, use the Scirocco system and install the injectors in the four air tubes of a 140 - 4-bbl manifold. If you wanted to install a 6-cylinder version (like in my wife's 2.6L Benz), it would be more precise, but actually much more complicated, since you would have to modify the intake manifold, weld on injector bungs and so on.



Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
66 Red Monza 2dr 140/4 EFI 60k
61 Seamist Jade Rampside 140 PG
65 Cypress Green Monza 140/4 4dr
65 White 4-dr 110/AC/PG (parts)



19 Tons of parts in boxes

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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 17, 2008 03:42AM

I'm pretty surprised that there haven't been many responses to this. I consider it a fairly significant discovery. Granted, Tom's hardware looks pretty grim. Perhaps if I took a shot of the same system on my wifes nice shiny Benz, there would be a little more enthusiasm. Last week, everybody was asking "Why isn't there a low-cost FI system I can put on my Corvair". Well, here it is, in concept. Fuel pump, Air meter, O2 Sensor, 4-injectors in the intake pipes. It ain't gonna get any simpler than that and this is a full-feedback system.

Bosch calls this their CIS injection system and there were millions of vehicles sold with this system in the US. Earlier CIS systems (pre '81) did not have the O2 feedback and are to be avoided except where the engine displacement of the donor is very close. (A glace at my Bosch manuals found some BMW product in the range). Earlier systems had irregular "Hourglass" shaped cones in the air meter and the profile of the hourglass determined fuel delivery at various airflows i.e. a specific engine profile. Later CIS systems with O2, like the one Tom unearthed, don't have the irregular hourglass, but instead have a generic profile and the O2 matches the air and fuel for a consistent 14.8:1.

Since this particular system (Scirocco) has net horsepower in the same range as the Corvair, there's an extremely high probability that it will function very well. Note that some air cooled Porsches came with this system (80-83 911SC), so there is an engine temp sensor that's right for an air cooled motor.
Cool stuff!


Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
66 Red Monza 2dr 140/4 EFI 60k
61 Seamist Jade Rampside 140 PG
65 Cypress Green Monza 140/4 4dr
65 White 4-dr 110/AC/PG (parts)



19 Tons of parts in boxes




Edited 1 time(s). Last edit at 05/17/2008 03:44AM by cnicol.

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Re: Low cost fuel injection
Posted by: UGLYTRUK ()
Date: May 17, 2008 04:02AM

Oh.... If I only had the time... Used ta tinker... Now my day is cut into 5 minute increments... shame...

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Re: Low cost fuel injection
Posted by: lgoodwin ()
Date: May 17, 2008 04:04AM

So, I guess you do something to mount each injector in the middle of the intake tube? Would not have thought of that. I thought the injector had to be inserted into the top of the chamber for proper mixture/flow or whatever...

I've been wondering if there were any mechanical fuel injection systems from existing donors that would make for an easy conversion. If it was good enough for early Corvettes, should be good enough for the humble Corvair.

I had a '77 Audi with the early CIS mechanical injection system that I bought for parts for my '74 carbureted Dasher. Is this the same unit?
Are all the K-Jetronic units the same? I see them for BMW and Porshe.

Please post detailed instructions and photos on this forum when you get it done!

1962 Corvair 900 sedan1967 Corvair Monza 140/4-speed1968 Corvair 500 coupe1983 Mexican Mustang 5.0
1962 900 sedan needs a home1967 Monza 140/4-spd1968 500 coupe (now my son's)1983 Mexican Mustang 5.0

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Re: Low cost fuel injection
Posted by: Vairforce1 ()
Date: May 17, 2008 04:11AM

Found an interesting website and a book on this topic:

Retro-fitting Bosch CIS (K-Jetronic) fuel injection to air-cooled type-4 VW engines
[www.aircooledtech.com]

Bosch Fuel Injection and Engine Management / Charles Probst
[www.amazon.com]
[www.worldcat.org]

And here's something to consider: the six cylinder CIS injection system might work really well with those cool tri-ported heads the LeVeques modify. Since the intake logs are milled off, you could place the injectors fairly close to each intake port, thereby eliminating the icing problems inherent with the center-mount carb on top of the long intake runners. And with the extra breathing capabilities of the tri-port head, this would be a pretty strong performer, too.

Dave Muhlena
Cedar Rapids, Iowa
'65 Corsa 140 project - going nowhere, fast!

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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 17, 2008 05:14AM

I have the Charles Probst Bosch book in front of me and it covers the system in great detail, along with about ten other Bosch systems. Excellent book, evenif it is a little dated (1991).

As for Luke's comment about needing to inject near the top of the cylinder, except for the very latest GDI engines (which inject directly into the cylinder at extremely high pressure, like 10,000 to 20,000 psi) the opposite true. Even on a mulitport EFI, the injectors are 2 to 4 inches away from the intake valve and injection occurs when the intake valve is closed. (usually in two puffs). This allow some delay time so the atomized fuel can vaporize in the partial vacuum of the intake. Warmth helps too. If a carburetor can spray atomized fuel at the cylinder head intake port, and injector can do exactly the same thing, plus the fuel will be in smaller droplets than a carb can manage so the mixture will be more homogenous (leaner mixture won't detonate).

No, K-jetronics are not all the same. There are four versions. The earliest, like your Audi had, were purely mechanical. Later ones phased in an O2 sensor, and even later ones, KE-jetroincs electrically altered the mixture rather than mechanically. KE Motronic controls spark too.

The mechanical ones (what we are talking about) are rather like the Rochester units on the old Corvettes, but are FAR more reliable and the later mechanical units, had O2 feedback, which is key for Corvair application and the efficiency we all seek.
Craig

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Re: Low cost fuel injection
Posted by: SpyderMan ()
Date: May 17, 2008 05:31AM

I have had a number of water cooled VWs with CIS systems and they all worked very well. I guess what I do not get is how the system you are talking about using is going to work on a motor that is full liter larger?? I think the hole and the plate that controls the amount of fuel coming from the fuel distributor is designed around a 1.6, 1.8 or 2.0 motor and the o2 adjusts from there. Do you think it can make up that kind of difference?? I am all for it by the way, if you can make it run well the parts cheap plentiful and rock solid. Some one on here was talking about trying to install CIS off of a Volvo a while back, you guys remember that??

Sam Russell
Chapel Hill NC
1962 Monza Wagon
1964 Spyder coupe


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Re: Low cost fuel injection
Posted by: Tom Z ()
Date: May 17, 2008 07:15AM

..I'm not sure what this unit came off,but my intentions are to pick up the 'vapor carb' project I started 'way-back when...a few things need to be resolved in the 'heat exchanger' systems that have been around for decades,one being cold starts and better control of the fuel/air into the exhanger..carbs just don't have my vote,but the simple Bosch injection would help determine just how 'lean' the fuel-air ratio can be..the intake 'disc' lifts up with air flow,moves a 'beam' that has a sliding valve (simply put..) that alters the fuel rate to the injectors on the other end,and *could be* operated independent of the 'throttle' setting...I may only need 2 injectors to spray into the miniature 'boiler' to vaporize the fuel BEFORE it enters the cylinder,which will result in more MPG/less crankcase contamination..Ray Covey,a Texan,did a setup on his 400-CI Dodge sedan,and claimed 79.8 mpg on a series of runs with full power,but also added a 'bubbler' system that drew fumes from the gas tank..realistically,I'm shooting for tripling mpg,not just adding fuel injection for the 'cool'factor ..yes,Craig,it's going to take some work to get this operational, this unit was in the trunk with more misc parts,and lacks the needed fuel pump..

Tom Z,,Rochester NY


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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 17, 2008 01:13PM

To answer Sam, while the standard VW with CIS was rated at 78 net HP, the system was no doubt up-sized accordingly for the Scirocco, which was rated at 113hp. If it can flow enough air to support 113 hp in a Scirocco I don't see why it wouldn't do it for a Corvair. Remember a 140 is rated at 109hp net and a 110 is 88hp net.

I'd like to find some specs somewhere and compare the CIS air meter diameters between various engines. The CIS system was applied to engines big and small, the big end was 5.6L. Aside from basic capacity differences, the system has some adjustability; there's a basic fuel rate scaling called the CO adjustment and idle air is also adjustable.

Something I'd like to know is whether the Scirocco sensor is updraft or downdraft, CIS came both ways and clearly downdraft is better for our needs. I have no doubt that the 2.7-3.0L Porsche versions or the 2.6-3.0 Benz versions are well suited but if we find the Scirocco air meter is anywhere near the diameter of those units, the simplicity of 4-injectors throws the pendulum that way.

Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
66 Red Monza 2dr 140/4 EFI 60k
61 Seamist Jade Rampside 140 PG
65 Cypress Green Monza 140/4 4dr
65 White 4-dr 110/AC/PG (parts)



19 Tons of parts in boxes

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Re: Low cost fuel injection
Posted by: Tom Z ()
Date: May 17, 2008 01:48PM

..I think the smaller 'Rabbit' system would work well enough if the 4 injectors were located in the 140 air cleaner runners,above the gutted carbs,allowing the stock throttle linkage to work the carbs, with a link connected to the fuel distrib 'beam' to vary the fuel rate..the 5th 'cold-start' injector could go in the stock air cleaner top-cover,next to the long 1/4" stud..it may/may not flow enough at full WOT, but for the street-driven car that shouldn't be a problem..

Tom Z,,Rochester NY


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Re: Low cost fuel injection
Posted by: gmgmtl ()
Date: May 17, 2008 03:57PM

This ecotech marine engine might be not be low cost and a bit off the wall, but at $1150 cheaper than a rebuilding a corvair engine to use modern fuel injection efficiently. Converting to this engine would be near equal to installing a V8.
See crate engine on link.

[www.ecotecmarine.com.au]


Gary Moore near KC Missouri

"The internet: A magnificent new technology combining the credibility of
anonymous hearsay with the excitement of typing." Jon Stewart 2004

61 RedRampside 110 automatic
61 Green Rampside 102 4speed

Heart of America Corvair Owners Association
[www.HACOA.org]

Corvanatics
[www.corvair.org]

Cactus Corvair Club
[www.cactuscorvairclub.com]

Google CORSA Chapter Map with links to chapter sites.
[maps.google.com]


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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 17, 2008 05:13PM

$1150 cheaper than rebuilding a Corvair engine? I'm confused! The CIS system in question will probably cost $100 at a boneyard, plus a new pump and filter. A conversion would also need a 4-bbl intake setup.

The two EFI Corvair engines I currently have are bone-stock except for the head modifications. The CIS conversion would require no mods to the engine except for maybe a cam with less overlap. Fuel economy, increased engine life, and better driveability, not to mention the fun of tinkering.
Craig

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Re: Low cost fuel injection
Posted by: gmgmtl ()
Date: May 17, 2008 05:29PM

I am talking a complete rebuild which may or not be needed to make the Corvair engine as efficient as a modern day injected engine.

Gary Moore near KC Missouri

"The internet: A magnificent new technology combining the credibility of
anonymous hearsay with the excitement of typing." Jon Stewart 2004

61 RedRampside 110 automatic
61 Green Rampside 102 4speed

Heart of America Corvair Owners Association
[www.HACOA.org]

Corvanatics
[www.corvair.org]

Cactus Corvair Club
[www.cactuscorvairclub.com]

Google CORSA Chapter Map with links to chapter sites.
[maps.google.com]


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Re: Low cost fuel injection
Posted by: RAV_AIR ()
Date: May 17, 2008 06:28PM

I'm confused. would there eventually be six injectors? if not you've got one injector that has to do twice as much or both doing 1 1/2 times as much work....I don't know how you could program that...


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Re: Low cost fuel injection
Posted by: beaulieu ()
Date: May 17, 2008 09:45PM

there are 2.8 amd 3 liter BMWs and Mercedes using this injection ,

and probably Volvos too,

If you were going to use the 4 banger parts you could use larger injectors off of a larger cubic inch motor ,

its an interesting idea , I hope someone does it !

Beaulieu

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Re: Low cost fuel injection
Posted by: cnicol ()
Date: May 17, 2008 09:46PM

Ah, GMoore, I see what you're saying. I'm not sure we could ever get to modern standards because of the 4-valve, variable intake and exhaust timing, split ports, roller cam yadda yadda. However if one looks at the gross factors that are way off, that would be combustion chamber and lean mixture pockets (non-homogenous charge density) in an overall rich mixture, engine friction, and volumetric efficiency. We can get most of the way there by improving the chamber design to promote squish and tumble, fuel injection, and a more up to date gearing and cam combination. The gearing and cam issues are easily solved with a 3.65/3.08 trans & axle combo. The PG140 cam is an off the shelf answer to the cam side, though there are probably better solutions there. Fixing the intake and exhaust flow is doable (fabricated intake like leVeque six-tube and slant tube exhaust) but that's moving us to the costs you mention.

My shopping basket includes
3.08 gearset
3.65 trans to recover the takeoff
Torque cam with wider lobe separation
FI
140 engine with dual exhaust

My '66 has most of this, but has the wrong cam :-(, (it's a 304, not enuf bottom end). The '67 I just sold had all of it except for the FI and it was a terrific car to drive.

RAV_AIR, the number of injectors does not have to equal the number of cylinders (30 million 6s,and V8s have only two, for example). The CIS system has no programming, but if it did, being continous injection, (spray) all you would do is to program more volume.



Craig N. Coeur d'Alene ID.
66 Black Monza 4dr, 4.2L V8 49k
66 Red Monza 2dr 140/4 EFI 60k
61 Seamist Jade Rampside 140 PG
65 Cypress Green Monza 140/4 4dr
65 White 4-dr 110/AC/PG (parts)



19 Tons of parts in boxes

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Re: Low cost fuel injection
Posted by: RAV_AIR ()
Date: May 17, 2008 09:53PM

RAV_AIR, the number of injectors does not have to equal the number of cylinders (30 million 6s,and V8s have only two, for example). The CIS system has no programming, but if it did, being continous injection, (spray) all you would do is to program more volume.<<<<<<<<<<<<



Ah, I get it. thanks for the clarification.

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