Ford/ Saab Cologne V4 MFI + EFI conversion projects

[melle]

This thread started with a few questions about using Ford V6 EFI parts for a V4 injection conversion, and was then turned into a project thread.

I'm (slowly) building two fuel injected Ford Cologne 1.7 V4 engines ("Taunus" engines, not Essex V4s). The first one will use Bosch K-Jetronic MFI and VAG Hall ignition, the second one I plan to build as an EFI engine using Megasquirt or a similar retrofit stand-alone ECU. They will be mildly ported but otherwise standard street engines and I'm building them "just because"; I'm not after outright power or anything.

I can't get to my workshop for the foreseeable future due to the corona situation, so I'm doing some more desk engineering before continuing the actual builds. For the first engine I have all the parts, a plan of attack and lots of parts already built, I need some advice regarding the second one.

I'm thinking of hacking up a Sierra 4x4 2.9 V6 EFI manifold and plenum to fit the V4. I have two different types of those and I'm pretty sure I can make one fit with a bit of machining and welding (not sure which one yet). The 2.9 uses Bosch EV1 injectors, which are cheap and easy to get (I have 2.9 injectors and ones from a Fiesta/ Escort, which should deliver about the right amount of fuel I guess). If the TB butterflies turn out to be too big for my wee 1.7 engine, I'll knock up an adaptor plate and fit something smaller.

I know my way around the K-Jet system fairly well (I have a K-Jet Saab 900), but I have no experience with EFI. I've ordered a book to get a better understanding of what I'm doing, but in the meantime I have two questions:

- The 2.9 V6 manifold has a dual plenum with a separate air intake for each head, and it also has two MAFs. Why two, and can I merge them into one? I was thinking I could siamese the ducting between the plenum and the TB and fit one MAF with a cone air filter.

- I don't have any 2.9 V6 MAFs; should I get a set, or is it better/ easier/ cheaper to fit something else? If so, any recommendations? I prefer using standard parts that I can easily (read: cheaply) get from the scrapyard/ eBay.

You can see the 2.9 V6 MAFs at the right hand lower corner in this pic, they look rather bulky to me:

[kevins]

The vane air meters shown are old technology and quite restrictive (that's why they fitted 2) if you want to use a mass airflow sensor hot wire sensors are simpler and less restrictive. That said assuming you are not planning to meet the latest emissions standards an even simpler speed density system will work fine and is what most after market systems are set up for, these use engine speed and manifold depression to calculate the amount of air flowing into the engine.

having injectors and throttle bodies meant for a 2.9 is unlikely to be an issue either, it is possible to go so large they can't meter the small quantities needed at idle but that's when you are talking injectors designed to flow enough for 600hp, not the 160 odd the 2.9 produces, too large a throttle can make it too responsive and difficult to drive at low speeds but again the 2.9 was always set up for smooth response so I can't see this being an issue either.

As to how the manifold is designed will depend on what you are looking for, paired longer tracts are usually designed to boost lower end torque, shorter independent ones will be better for power. they are usually paired with the cylinder that fires 360 degrees away(so on an inline 4 that would be 1 and 4 and 2 and 3.

[Phil H]

If going Megasquirt, you don’t need air flow meters but you do need to add an air temp sensor in the plenum - it uses the temperature and the MAP signal to figure out the mass of air. Ford fitted the air temp sensor in the flow meters..well, the6 fitted one in each but only read from one of them.

As for injector sizing, it’s per cylinder. A 2.9 with 170bhp equates to suitable for a 125bhp 4 cylinder so about right. I think the hardware was unchanged for the 2.4 V6 so pro rata it’s still about right.

[Phil H]

Good point raised on the firing order - the V6 goes left/right down the banks. If the V4 doesn’t, you’ll end up with charge robbing so would do better with a single box plenum. There’s a formula for optimum volume as well - 2 to 3 times the sweet volume rings a bell for some reason between the throttle and inlet valves. Rarely achievable in reality though!

[melle]

Thanks kevins and Phil H , some good feedback there.

– I'm not yet set on what ECU to use. The book I've ordered is written by the founder of MS, so probably biased in that direction, but I'll read up on alternatives as well. I'll buy a Sierra V6 Haynes too to get a better understanding of the original Ford layouts.
– Regarding injector cc: I'll try the V6 ones first and see what AFR and performance that results in. I've found an Excel sheet with specifications for hundreds of EV1 injectors, so it should be possible to identify something that delivers more or less fuel if required. I wish something like that existed for K-Jet injectors!
– If the huge TB appears to be an issue it shouldn't be a problem to get something smaller from the scrapyard and make it fit, either single (if I remove the baffle in the plenum) or twin butterfly (if I don't). If anyone has ideas on TBs with the same stud spacing I'd be happy to hear from them, but not sure if it's some kind of standard like you find on carbs.

Apr 21, 2020 14:05:56 GMT Phil H said:

Good point raised on the firing order - the V6 goes left/right down the banks. If the V4 doesn’t, you’ll end up with charge robbing so would do better with a single box plenum. There’s a formula for optimum volume as well - 2 to 3 times the sweet volume rings a bell for some reason between the throttle and inlet valves. Rarely achievable in reality though!

Not sure I fully understand this. The V4 firing order is 1-3-4-2, the cylinders are in this order:

Front

3 1

4 2

Back

I've never seen a complete 2.9 V6 in real life, only got some intake parts off eBay, so don't know about those. I assumed the 2.9 has batch injection (i.e., the injectors squirt simultaneously) on basis of the injector loom that came with one of the manifolds I bought, so firing order shouldn't be a problem? I'm probably missing something! I'll need to hack up the plenum anyway to shorten it, so if desirable it'll be easy enough to remove the baffle between the two sides and transform it into a single box. Do the simpler MS ECUs (don't think I'll need a fancy one) allow for sequential injection, and (how) would that be beneficial?

[kevins]

sequential injection injects the fuel as the inlet valve is opening so it's drawn directly into the cylinder and gives a more accurate and homogeneous mix of air and fuel which helps emissions and fuel economy and possibly a little extra power.

This is important in the world of modern cars with very tight emissions and CO2 requirements but probably not going to be noticeable on a 60's engine.

I'm sure your throttle bodies will be fine, my Lotus runs 4 40mmm throttles on a 1550cc engine and is perfectly driveable.

[Phil H]

You’ll suffer charge robbing if you have the plenum split left/right):

The V4 firing order is 1-3-4-2, the cylinders are in this order:

Front
4 1
3 2
Back

V6 is 1-4-2-5-3-6 with:

Front
1 4
2 5
3. 6
Back
V6 goes left-right-left-right-left-right
V4 goes right-left-left-right-right-left-left etc.

That means you’ll end up with suck-suck-rest-rest from each side, leading to a very uneven airflow. Does nothing for maintaining air/fuel ratios and it won’t be sequential on that - needs a cam sensor for that. I think the 24V does, but not the 12V.

[melle]

Thanks again both, the effect of firing order on the dual plenum set-up is something I'd never considered, so very helpful info again!

[mk2cossie]

24v is batched injection, 1,3 and 5, and 2,4 and 6 I seem to recall.
As said above if you are going to use MS or equivalent then you wont need to use MAF sensors on there. Just use a MAP sensor and throttle position for load sites.

On the MFI setup, it may be worth looking to use a metering head off of a mk2 Golf GTI as they have individual fuel trims for the injectors.

Sounds like a couple of interesting projects tho

[Phil H]

The 24V isn’t sequential injection either then.

Just a thought for some desk engineering - see if the hardware bits (injectors mainly) are the same for the 2.4i and 2.9i Granada. If so, then they should be fine for your mildly warmed 1.7

[melle]

Apr 21, 2020 21:55:25 GMT mk2cossie said:

On the MFI setup, it may be worth looking to use a metering head off of a mk2 Golf GTI as they have individual fuel trims for the injectors.

That's what I'll be using I think, they come with nice braided fuel lines from the factory as a bonus. I have built up a nice collection of Saab, Volvo, Porsche, Audi, Ford and VW K-Jet parts to play with. Just not sure on what injectors to use, can't find much info on them .

[melle]

I've been busy cleaning another 2.9 manifold and plenum today. Hopefully this thread can go to the projects section in a while, but for now that's what needs to happen first as I don't like working with mucky parts. I have a parts washer in the workshop, but a little elbow grease gets me there as well if needed; I find it weirdly satisfying to clean castings for some reason.

Does anyone happen to have PDF parts books for the 2.8 and 2.9 injection engines? Please let me know and I'll PM you my email address. I'll also consider "real" parts books if the price is right. I'm still missing a few parts, will post a wanted thread once I know what I think I need. In the meantime, if you have any surplus 2.9 EFI parts, please give me a shout.

[melle]

I assumed I had two different 2.9 EFI manifolds, but I learnt yesterday one is an ultra rare 2.8 one, apparently Ford used this for one model year before the 2.9 was introduced.

The one to the left is 2.9, the right hand one is 2.8:

(Forgot to flip the 2.9 plenum over for this pic, but you get the idea...)

Apparently 2.8 and 2.9 heads and inlets are not interchangeable (so 2.9 inlets can't be used for a 2.0/2.3/2.8 EFI upgrade), but I think I can make either manifold fit the V4. I used a template of a V4 inlet manifold gasket from my website printed on transparent paper to check the fit. The V6 is 12cm longer than the V4, and that's the amount the manifold will need shortening; the middle ports will have to go.




A little port matching will be needed, but that also is the case with standard V4 manifolds because "that'll do" was apparently good enough for Ford.


The 2.8 manifold came complete with TB, injectors, fuel rail, injector loom, idle valve etc, but I only have a fuel rail with injectors for the 2.9 one. That being said, I'm worried about the total height and bonnet clearance in a Saab 95/96 and it looks like I can get away with milling 1-2cm off the 2.9 manifold and plenum combined, so although I need to find more parts that's the most likely candidate for this conversion. Lower engine mounts is another option, but I'm afraid I need those anyway to make sure the plenum clears the bonnet cross bar. The water channels in the manifold will need modifying, I'll talk about that later, and the 2.9 manifold is the best candidate for that as well. I have to say I like the looks of the 2.8 manifold with the shield over the TB, I may use it to convert a 2.3 V6 I have should I ever get bored....

Apr 21, 2020 22:03:10 GMT Phil H said:

Just a thought for some desk engineering - see if the hardware bits (injectors mainly) are the same for the 2.4i and 2.9i Granada. If so, then they should be fine for your mildly warmed 1.7

I still haven't been able to find out what injectors the 2.4 uses, but I found the injectors I have in this spreadsheet:

Type	Bosch part number	Resistance	Test medium	Operating pressure	Q-stat (at operating pressure) (g/min)	Q-stat with 300 kPa (g/min)	Q-stat with 300 kPa (ml/min)	q-dyn with 300 kPa, ti 2,5 ms (g/1000 Imp.)	Spray type	Spray angle alfa-80 Spray distribution (area, spray amount)	Spray distribution (area, spray amount)
2.8	0 280 150 219	16.15 Ohm	Ch20v3	250 kPa	131.8	144.4	206	4.33	A	18˚	8°-30° >40%
2.9	0 280 150 727	14.4 Ohm	Heptan	270 kPa	103	108.6	155	3.44	A	14˚	8°-30°>70%
Fiesta/ Escort	0 280 150 743	15.9 Ohm	Heptan	300 kPa	150	150	214	4.87	A	19˚	8°-30° >40%

I'm not claiming I understand all the information, but it looks like the 2.8 injectors have a higher flow rate, at slightly lower operating pressure. We'll see what works I guess, the dimensions are identical so they can easily be swapped over if needed and if nothing works there are hundreds of other ones available. Not the greatest worry at the moment, testing is probably years away anyway!

[mk2cossie]

That is indeed the rare 2.8 efi inlet. Fitted to the 1985 (possibly) mk3 Granada in the UK (and know as Scorpio elsewhere)
If you can avoid it, DON'T chop it up! It will be a good source of income if you sell it on

Also meant to be a good upgrade for the 2.8 MFI as it apparently flows quite well!
Especially compared to the original 2.8 inlet with 4 inlet ports

[melle]

No worries mk2cossie , it would be stupid to chop it up, mainly because the 2.9 manifold seems to work so much better for what I want do do with it. There's one on eBay for £270; it's missing the TB shield and mine's in cleaner condition, so I'll keep that in mind for when I need funds for this project.

I have one of those 4-port 2.8 K-Jet manifolds as well. It wouldn't be easy to chop 12cm out because of the way it's designed, and the square plenum looks proper horrible too. For my K-Jet engine I'll be using a modified standard V4 manifold, I'll write about that some other time.

[melle]

Parts wanted.

[melle]

After reading Kelvinator 's excellent Rover SD1 thread (sorry for the sad ending...) I'm leaning towards buying a Speeduino kit.

[Kelvinator]

This is a very interesting project and I'll be following along.

Speeduino is a great system to work with. Powerful enough, yet simple enough even I could get it working.

Out of curiosity, since you have the 2.8 mfi and 2.9 efi manifolds there, can you see the differences that apparently stop you swapping the 2.9 manifold onto the 2.8?

I intended on converting my 2.8 mfi TVR to Speeduino using a 2.9 efi manifold the car came with, but a combination of hearing the manifold doesn't fit, and getting the non-running kjet working properly again means I have stuck with the mfi.

[goldnrust]

Is the v4 an even fire engine? i.e. does each piston fire 180 crank degrees apart? Or being a 60 degree v4, is it odd fire like some V6s and V twins, where it fires the cylinders in a 150-210-150-210 type pattern?

I mention because when I was looking into it I'm pretty sure Speeduino only supports even fire, whereas Megasquirt will do both. I've done several Mehgasquirt builds but if I do another EFI conversion Speeduino certainly looks interesting.

I'll be interested to see how you get on with Speeduino if you go that way.

[melle]

Kelvinator, I searched this forum for Speeduino and your thread was the only one that popped up. Quite surprised not more people on here are using it (or they may be keeping it to themselves of course).

Regarding 2.8/2.9 manifolds: the shape of the ports to the heads is slightly different on the 2.8 and 2.9 manifolds, but nothing a carbide burr couldn't sort I'd say. I think the main issue is that the cooling layout is different, the 2.9 has the thermostat in the intake manifold whereas on the 2.8 it's in water pump as far as I know. Doesn't really matter in my case as it'll be a hack and weld job anyway and I could use the front/ thermostat part of a V4 manifold if needed.

K-Jet is great, but fault finding/ fixing can sometimes be a pain. I've had a slight idle and hot start issue on my Saab 900 for about eight years. It wasn't stopping the car from being usable, but annoying enough to look into it twice a year or so. I've never been able to figure out what was wrong, until I spotted some discolouration on one of the (plastic) fuel lines last summer. At close up there appeared to be a tiny crack, and replacing the fuel line has completely solved the issue. I'm planning to replace the fuel lines with braided ones at some point, but for now it's running fine and it's not getting much use anyway at the moment...