Questions on distributor-less ignitions.

[chrispy]

Fred,

Thanks for putting Electromotive in front of me again. Just spent the last while reading up on their website. Let me put it to you this way, I AM SOLD. Do not really care what it costs (hopefully the dealer who sells it to me does not see this).

First let me say that their website is very informative. So much so that no email is required. Even better yet their manuals are the best I have ever seen in the after-market world. Honestly whomever writes for them should be given some type of award. I am sure that we all know how a distributor-less system works in theory. Want to be an expert (or about as close as you can be just from reading) read Electromotive's manual on their XDI system. It should be named "This is how distributor-less ignition works, using XDI as an example". It was actually fun to read.

Link to manual for the XDI system:
http://www.distributorless.com/pdf_f...di_man_1_2.pdf BTW check out the domain name, nice attention to detail.

Now imagine adjusting advance using a knob on the dash (or hidden under it like it should be). Even more fun it would be linear to what is already programmed.
Also has a Nitrous retard curve as well, also linear. Using an input feed from the N20 relay.

So I was sold on this. Read some reviews as well. All seem positive (than again they all do).

So then I wondered over to the TEC3 fuel management system also from Electromotive. First question was, how does it integrate, with the XDI ignition system??? Well I was wrong in my first assumption. The TEC3 system is not just fuel management system, it also does the spark control. Just what I was looking for. Even has a atmosphere sensor (boost sensor), and intake temp sensor. Perfect for turbo or supercharged applications. Even has the ability to control N20 as well. Thanks to it controlling the injectors, you would not need a wet N20 system, but could use a more controllable dry system.

They do use only a crank trigger. No cam trigger. Problem is they have no crank trigger for a FE block, you have to use the universal and machine it. Everything else but.

The manual is even more insane for the TEC3 system. Same thing can be said. If you want to learn all about ECUs read their manual.

http://www.directignition.com/pdf_files/tec3r.pdf

BTW when was the last time you got a 164 page manual for any aftermarket product.

There is only one question that arises for me. It has to due with the coils used. I had thought that you needed 1 coil per cylinder. The system would trigger that particular coil to fire. With their system you need one coil per two cylinders. There is only one trigger for each coil. Each coil connects to two cylinders that are 180 degrees apart. Why would this be? To save the number of coils is the only reason I can think of. Or is there an advantage to firing the other plug when it is at BDC and the other at TDC (or whatever timing)?

Another thing that peaked my interest is the almost true linear timing curves.

Another is the "valet"switch (just a rev limiter, another timing curve would of been cool as well especially for BBs). Could also be useful when you let someone else drive your beast.


Thanks again,
Chris

PS I can close out this part of the build sheet.

[chrispy]

OK nobody needs to answer the question on the one-coil two cylinders. Just learned that this is what they have been calling the "waste-spark" system. I was also wrong it is 90 degrees apart (exhaust stroke), not the 180.

Also explains the issue with Bosh and there platinum plugs, and why Ford uses different plugs on different sides of the block in a waste-spark system.

Chris

edited my mistake out calling it waste-gate

[CSX4815]

Chris,

It's called a "wasted spark" system. The spark plug with the most resistance fires the majority of the energy. Even though the other plug (the one not on the compression stroke)fires it receives much less energy than the cyl on the compression stroke. Don't ask me how this works...I was told all of this (and a lot more that went in one ear and out the other) by the tech support guy at Electromotive.

I might add, look at the Motec I have been shopping systems and have settled on the Motec system. Download their catalog and it is also good reading. One warning though...be sitting down when you see the prices! High end stuff from what I understand.

Mike

[ffindling]

Chris - These systems will operate with
only a crank trigger in batch mode, but
camshaft position sensor input is required
for true sequential operation. This is all
explained in the TEC3 manual which as you said is well written. Mounting the
reluctor wheel and the hall effect sensor
for the crank trigger is pretty simple. You'll
have to fab up a little bracket to hold it.
Hidden in depths of this site are several
photos of a sensor bracket that someone
fabbed up for an FE install. George Anderson as I mentioned earlier has what
he calls an EFI oil pump drive - distributorless ignition which is made
out of an MSD distributor body. This nifty
piece gives you a camshaft position sensor
output. This no doubt would be much easier than mounting a sensor on the
timing cover and fixing a magnet to the
camshaft sprocket.

Gessford Machine scroll to bottom of page

.....Fred

[chrispy]

Fred,

You are indeed correct. I misplaced that particular sentence. That sentence "it will only need the crank sensor", Should apply to the XDI, and not the TEC3 system, if you want to run sequential.

Chris

[ffindling]

Chris - Waste gates are used with exhaust-driven turbochargers. It allows
boost to be regulated by dumping unneeded exhaust gas out directly rather
than routing it into the turbo. The TEC3
can be used to control the waste gate
allowing it to regulate boost.

....Fred

[chrispy]

Mike,

Thanks for the info, guess I was not quick enough with answering my own question. Which was answered by their manual.

The compression stroke receiving the energy (or amps) is understandable to me. Let us just call it physics (my head hurts to much to try to explain). In very, very simple terms ( did I say very), think path of least resistance.

Thanks for the tip on the Motec system. Are you looking at the M800 system? I swear I was on their website on and did not see it.

One thing that I am trying to figure out is combining ignition and fuel management system. Now I am thinking out loud here, and very vague. Lets say that the 02 sensor in your fuel management sees something it does not like. Now with a combined system, one of the options available would be to adjust the timing accordingly. It seems the TEC3 system works this way. I did ask if the FAST and eDis system could work this way (being separate boxes), but got not response.

Now I see Motec has a combined system with their 800. I swear I looked at their web-page yesterday and it was not there. Thanks though, now I have another option, but I have to admit the TEC3 boiled me over.

I did see the pricing on these systems, Do not really want to think about that part at the moment. Buy a couple of high-powered laptops or an ECU.


Thanks again,
Chris

P.S. I did mention "very simple terms" please no flames. LOL

[chrispy]

Fred,

You are once again correct. You should get a star

Got my terms mixed up. Late here, EST. Waste-spark is indeed the correct term.

[chrispy]

Fred,
In general terms waste-spark would be for emissions????

I can see no other advantage to it with the exhaust port open.

Chris

[CSX4815]

Chris,

I am looking at either the Motec M48 or the M800. Both of there units will operate in full sequential mode with 8 cylinders. The M400 I think is for a 4 cyl. engine in full sequential mode. The catalog has all the units as well as accessories and prices.

I am building a 526 Shelby with the TWM setup and the guy that is doing the dyno tuning and setup for me is an ex Motec employee and is most familiar with their systems. The one big selling feature that was pointed out with the Motec units is the great degree of adjustment (trim) that they offer. Also that they have increased memory for data logging than some of the other units on the market and depending on the sample rate used can record data for quite a while. The M48, as a Motec tech guy told me is the older technology of the two compared to the M800. The M800 is the newest technology with the latest windows interface and has all the whistles and bells including traction control, drive by wire and even remote data logging telemetry. Way more than I would ever use.but pretty neat stuff non the less.

Mike

[ffindling]

Chris - I don't think waste spark systems
have any implications as far as emissions
go. Its main advantage is simplicity. By
sharing a single coil between two cylinders, you halve the number of coils
needed. Since the waste spark cylinder
is not under compression at the time of
firing, plug wear is of no significance.
Most of the energy ends up going to the
cylinder that is under compression because the plug in that cylinder is offering a lower resistance path to ground. So in effect, waste spark systems
use cylinder compression to manage
spark distribution. The auto industry has
been using waste spark systems since
the mid 80's and they are well proven.
Although some newer engine designs
such as GM's GEN III and Ford Mod motors (99 up) use coil-on-plug ignition systems where each plug has a separate coil, the main reason for this
was not out any preceived disadvantage of waste spark systems but for OBD II compliance reasons. OBD II mandates that the ECM or powertrain control module report misfire problems and return an error code for each specific cylinder.
By having a separate coil for each plug,
the ECM can determine which cylinder
has a misfire because the separate
coils give each cylinder its own unique
feedback source.

....Fred

[chrispy]

Fred,

Thanks again for the answers.

Of late I have been working on trying to find some books or documentation on fuel injection. Not a simple book........... For example, I am looking at injector placement within the plenum. Not to get into the details but I am unable to find any scientific info on the subject.

Does Fred the expert or any others have any good advice on a book of such or documentation???

Thanks again,
Chris

[ffindling]

Chris - I might suggest How to Tune and Modify Engine Management Systems by Jeff Hartman. (ISBN 0760315825) It's available from Amazon,
but probably any other Book Store (Barnes & Noble, Borders, etc.) can order
it as well. There really isn't a definitive book on EFI/management systems but Hartman's
probably comes as close as any of them.
There are plenty publications dealing with
specific OEM systems, GM, Ford, etc. but there are few generic
books on the subject. Funny thing is
that there are considerably more publications dealing with constant flow
systems (Hilborn, Enderle, etc.) and
mechanical systems. (Lucas, Telecamit-
Jackson, Bosch K-Jetronic, etc.) then ones
dealing with electronic systems.
As far as material on injector location/placement goes, that's probably beyond the scope of most
commonly available books. The technical archive of the
SAE Society of Automotive Engineers probably has a number of
engineering papers on that very subject. But if you go to their site and
search with the keyword "fuel injection," you'll get over 27,000 hits.
So you will probably have to narrow the
search with different keywords. You
can order whatever engineering papers
you want on-line.

....Fred

[chrispy]

Fred,
Thanks again for the info. I will try the SAE sight. I already have the book from Mr. Hartman. Although I did not go through it 100%, I may take a second look.

I am probably sure the SAE site will have what I am looking for. Might just take a while.

It does amaze me, that in its simple form, fuel-injection is that simple (apart from the calculations that the computer is doing). Far more simple than any carb, when you actually think about it. Bare bones injection needs just a MAP sensor, TPS and wires to the injectors. Done. Makes me wonder why.

At this point I plan on running TPS, MAP, heated O2 sensor, inlet temp, plenum pressure, water temp. One thing I do need to sort out is the EGR, but from what I can tell that is for emissions, and we do not NEED that. Although I do remember the late model Mustangs having and EGR with water running through it (at least I thought it was EGR). I can only assume that this worked with the same principal as a choke with water.

I do need to do some more research on the O2 sensor. The TEC3 system seems to only mention one (might be wrong), and I would think that 2 would be the way to go. Given the end cost of the system, why would I want only want one? Than I turn to the manufactures and see them running two (if a V8), so I think I will follow along.



Thanks again,
Chris

[CSX4815]

Chris,

Look again at the Motec M800. One of the differences between the M48 and the M800 is the M800 allows for two O2 sensors instead of just one. Makes a lot of sense to measure both sides of the exhaust instead of basing the engine management on just one bank. I know on my 02 Corvette there are 4 O2 sensors, both in front of and behind the cats. As I was told by the Motec guys, this was done for a reason!

Mike

[chrispy]

Mike,

Will definitely take a look at the Motec again. Maybe TEC3 forgot that there are still V8s in this world.

I agree it just seems foolish to base calculations on just one side. Makes absolutely no sense at all.

I do have to double check that the TEC3 does not support 2 O2 sensors.

Than again the Motech has that cool steering wheel interface. Have you seen that thing?
http://www.motec.com/products/steering.htm Not that it should be in a Cobra, but it sure would be fun building a car that it belongs in.

I need to find an oil pump drive. I did look at the Gessford website. Now I like to give the small guys my business, but "395.00$ w/gear (Brass gear extra)" seems awfully pricey????? As far as I can tell it does not have the cam locator in it either. How much does the original distributor cost???

I also am keeping an eye out on the used market. One thing I found and should share is at : http://www.motec.com/products/used_units.htm . Worries me, and as I read it, it seems the theft was from their plant.

Thanks again for all the help. Started ordering parts today.

Chris

[CSX4815]

Chris,

The billet distributer that George Anderson makes is from a modified distributer and I understand that it does have the hall effect sensor for the cam position sensor needed for full sequential operation. I personally think $395.00 isn't a bad price considering you are going to pay around $300.00 for a Mallory or MSD distributer and then have to pay again to have it modified for the efi sensor. I couldn't build this for $395.00 Just my .02. Good luck!

Mike



By the way, I just came back today from my engine builder, Shelby Enterprises, took them the TWM manifold for port matching and polishing and met with the fuel injection guys that are going to be tuning my engine. I know how you feel to be at the beginning of a "fun engine build"

[ffindling]

Chris - You probably won't have to deal
with EGR on replica car. Most people manage to register their cars in an emisions exempt category. EGR first appeared around 1973 as an attemp to
lower NO2 emissions. Since most OEM
intake manifolds have a heat riser passage that has exhaust gas passing
through it anyway, it was a simple matter
to install a vacuum-operated plunger valve that seated on the heat riser passage and when it opened it would
allow exhaust gas into the intake
section of the manifold where it would mix
with the air on its way to the cylinders.
The idea was that the spent exhaust gas
being recirculated would quench
combustion chamber temparatures to the
point where NO2 emissions would be reduced. In pre-ECM cars, the EGR valve
was usually operated by a coolant temp actuated valve. When the coolant reached a certain temparature, the
EGR valve would open. While EGR
may have reduced N02 emissions, it
also made the engine run lousy as one
might expect when you contaminate the intake charge with exhaust gas.
Back in those days, EGR was the first
thing that went when we de-smogged cars. You couldn't
simply take the valve off as that would
leave a hole between the heat riser
passage and the intake side. Easiest
fix was to simply swap intake manifolds
for an earlier non-EGR OEM manifold or
use a non-EGR aftermarket manifold.
If a non-EGR manifold wasn't available,
we'd either weld the hole shut or tap
it and screw in a steel plug. Then fab
a metal plate to cover over the hole
where the EGR valve was mounted.
Often just getting rid of the EGR made
the engine run much better with improved fuel economy. Since FE engines were phased out of passenger
car use in 1969, EGR is a moot issue
with them. Many aftermarket heads
don't have heat riser passages in them,
so EGR wouldn't work with them anyway.

....Fred