Questions about setting up fuel injection

[Matt S]

Hello everyone,

I'd like to solicit your opinions about what would be the best way to go about setting up a duratec with fuel injection.

Sorry in advance for the long post. I have many questions on this topic and am happy to learn whatever I can.

I recently acquired an SV with a duratec fed by twin webers. The car is running well right now and the more I drive it the more I like it. However, I can't help but feel that with the propper EFI setup this engine would have more to offer. So, what's the best way to do it?

Is it worth dealing with the OEM ECU? I could go to a junkyard and pull the entire intake and ECU from a focus or ranger and re-program the ECU. This would be the cheapest option (besides just keeping the webers), but what would I be giving up?

As fas as programmable ECU's go, which ones do you like and why? It seems like pectel is fairly common on sevens. Why would someone want a T6 over a T2?

I have been searcing blatchat about this for a while and I noticed that motec doesn't seem to be common on the sevens and many people like the emerald. What do you think of the emerald ECU?

Is jenvey the way to go with throttle bodies?

What else is needed, such as sensors, software, gagues, etc.?

Thanks for any input on this. I'm trying to figure out which way to go on this and where to best focus my energy.

-Matt

[JohnCh]

I have an Emerald on my Duratec and I love it. The product is affordable, very easy to use, has phenomenal support, and includes 8 channels of data logging. They are also getting ready to release some updates that will enable you to run a wide band O2 sensor directly into the ECU without something like an Innovate LM-1 to translate the signal, and traction control.

For the conversion you will need the ECU, throttle bodies, a coolant temp sensor, throttle position sensor, air temp sensor, fuel rail, fuel pressure regulator, injectors, and if your car isn't already plumbed for fuel injection then you will also need a fuel return line plumbed into the tank, ensure that high pressure fuel hose is used on the main feed, a high pressure fuel pump, and a swirl pot (assuming you don't have one built into your existing tank). The hardest part of my installation was the wiring, but that is because I built my own loom. At the time, Emerald didn't have one for a Duratec, but I understand that has changed (at least for a Caterham installation)

I have the Jenvey direct-to-head throttle bodies from Raceline and have no complaints. The SBD tapered units also have a good reputation, and then there is always the TWM units which are very nice, but a little pricey.

-John

[slomove]

If I remember correctly from looking at the car at the Streets the fuel rail and injectors were already there. Somewhat surprising together with the carbs. In the simplest case you could just plumb in the fuel pump/regulator to the rail with an Emerald ECU and use the Webers as your throttle bodies (venturis removed and without fuel supply). A little bulkier than the Jenveys but I would suspect they work just as well. Could save you a buck or two.

On the other hand the prices for used Webers are good on
e-bay
and the Webers could almost pay for the Jenvey TB. That is what I am going to do when I retrofit TBs.

Gert

[magnusfeuer]

The easy, although probably most expensive route to go here is to purchase a complete throttlebody kit from raceline or some other European company. You can also give Cosworth here in CA a call and see what they have.

The upside is that you get all the parts ready to install with a minimum of problems. The kit can be expensive though.

Sensors are not a problem, and are often already in place (although they do sometimes have to be replaced). A throttle position sensor (TPS) is often included in a throttle body kit. As Gert pointed out, your fuel rail is already there with injectors. If I remember correctly when having a look at your car while Martin had it, the submerged fuel pump had simply been disconnected and was replaced with a low pressure pump suitable for carbs. Easily reversed in other words.

You will also need to buy or manufacture the necessary wiring between the sensors and the ECU. If you can find a complete harness fitting a Caterham, it will save you a lot of work. At a price as usual.

Don't worry about maps, I'll help you out with that.

/Magnus F.

[Matt S]

The car is mostly ready for injection as is. It has a fuel return line that is capped off at the moment and it does have a fuel rail along with some unuesed plugs that I assume are for the fuel injection.

It seems like the choice of the ECU is a big one as it it the most difficult to change after the fact and many other choices depend on the ECU. I like the fact that the emerald ECUs are well supported on the caterhams and are affordable, but what can the pectel or motec units do that you can't do with the emerald? I would like to get the most power out of a stock duratec longblock that I can while maintining reliability and acheiving decent emissions and fuel mileage. Maybe that means I need to maps, one for power and one for "economy".

I think I will put in the ECU first and use the webers as throttle bodies and then swap them out for some jenveys later. It seems like I will be debugging less at a time that way. Are there reasons to just wait unitll I have all the parts and then put it all in at once?

I haven't spoken to cosworth yet aside from looking on the web site. The stuff on the web site is aimed at the focus, but I would assume that they would at least know what would be a good route to take with my engine. Maybe I'll call just to ask some questions.

Thanks,
-Matt

[magnusfeuer]

All modern club level ECUs such as the emerald will give you all the control you need over the engine.

A wide band O2 sensor capable ECU is recommended, as it allows you to map the engine "on the fly" (to a certain level of detail) without having to install a standalone sensor package. Check out peoples opinions on blatchat.com regarding different makes.

Higher end ECUs usually give you increased data logging, multiple maps, launch control, traction control, and other things you rarely need outside the professional race circuit. My T6 is, even if I am using it hard, a vast overkill for me; half of its sensor inputs aren't even hooked up.

The ECU usually turns out to be the platform from which you continue to upgrade your car. Once you have it and its wiring harness in place you can use more and more of it by adding race stacks, engine upgrades and other things to your car.

Sit down and think what you want to do with your car during the next couple of years and select an ECU that can match that migration path.

/Magnus F.

[Matt S]

Thanks Magnus, that sounds like good advice.

I am not quite sure how I will wind up using the car as I am still in the "I can't believe this car can do this" phase, but I envision using it for driving around town, blatting, autocross, track days, and drivers schools. I'd like to have an engine that is reliable, has clean emissions, and good fuel milage for driving aroun town and lots of power for everything else. Currently, when I am stopped at a red light, it REALLY starts to smell like unburnt fuel in the air. I can't help but feel bad about that.

Is it practical to run closed loop with a wide band O2 sensor and use knock sensors to adjust the timing?

I've got some thinking to do. I like the idea of being able to expand in the future, but I don't want to waste money on something I will never use.

-Matt

[slomove]

I think the reason for the popularity of the Emerald is that it does exactly what most people need (i.e. inject fuel and ignite at the right time) reliably and at pretty low cost. Easy to tweak and install. I am happy with mine and I have not even used the data logging feature (I use the Innovate gadget for that).

If you are a tinkerer you may want to try adapting the fuel/ignition with the lambda and maybe a knock sensor. But that could end up rather a sizable engineering project for the fun of it but a practical advantage. Getting a clean knock reading may also be a challenge due to the required signal processing.

Gert

[magnusfeuer]

Don't worry about getting a clean running car with a good mileage, as it is a consequence of a correct map.

Normally you try to focus on getting good mileage on the part of the map you use for city/highway driving while going a tad rich on higher RPM/load to avoid knocking with a bad batch of fuel.

It can be a hassle of getting a knocking sensor to function correctly since the ECU has a tendency of getting confused by the different engine harmonics reported by the knock sensor. A lot of people just setup standard ignition timing that is safe and call it a day.

Closed loop is only in effect when you are cruising on a constant speed/load where the parameters are stable enough for the ECU to fine tune its settings. Closed loop can adjust for varying humidity, intake air temperature, barmotetric air pressure, deposits in your engine etc, but will probably not have a major effect on your engine.

You can also add explicit modifiers in your map for
most of the factors listed above. Especially barometric air pressure and intake air temperature modifiers can make a difference, and will be in effect even when you are not cruising.

My limited experience with engine mapping has told me that it is pretty much an art (like adjusting carbs) where there is no absolute right or wrong. What I like in my maps may be hated by the next guy.

A typical example would be engine overrun (engine braking) where you can adjust how much braking you want the engine to do. When I helped Brad adjust his map, I routinely corrected a rich condition in his overrun profile, which he didn't like since it induced less engine braking (if I remember correctly). I had to reset that part of the map to the original setting.

Technically, his engine runs rich when he lets go of the throttle while in gear, but that is the way he wants it and is hence the correct setting.

/Magnus F.

[Matt S]

I didn't know that running rich on engine overrun caused more engine breaking, but it makes sense with what I have seen on my car. The carbs run quite rich at all times and I noticed pretty strong engine braking and hear lots of pops in the exhaust when doing so which I assume are afterfires due to a rich mixture. I found this out when I let the cluch out in second while coming into a turn fast without blipping the throttle and the rear tires chirped. I thought it was due to driving a car that is lighter than I am used to. It is probably a combiniation of both items.

I am currently trying to read as much as I can about engine management. Are there any good books you can reccomend? I am reading an online intro that is interesting so far:

http://members.aol.com/DVAndrews/ems.htm#topics

Also, do you know if the pectel units can send information from the sensors it has to a stack dash such as the 8130? While I have the luxury of not having to actually install or pay for anything at this stage, I can consider all kinds of options. :)

-Matt

[moosetestbestanden]

Give a look at http://www.sbdev.co.uk/Main.htm for a kit approach. My car has em on a 2.0L and it came out of the box running real well. Probably pretty pricey though, especially given the strength of our currency.

Btw, whose car did you buy?

[Matt S]

I bought Martin's car. He was the one with the Aluminum/Black SV at the streets.

I just got back from a short drive in it and it IS a nice car. However, it tends to sputter at light throttle. Oh well, I guess that means that I should only drive at WOT!!

-Matt

[Roll a 7]

I have Dave Walker's book and you are welcome to borrow it. Just give me a call and come on over!! It amounts to the Emerald text book.