Using OBDII engines

[Chris P.]

I've tried an OBDII forum but no one seems interested in my question. As you can see in my sig below, I will (someday) be building a car from scratch. Since I have to deal with emissions where I am (assuming I don't move beforehand), it will need to be OBDII. The easiest way is to grab a running OBDII engine. My question is, will this be possible or if putting a modern OBDII engine into a car with a different gearbox, overall weight, etc... will make the computer think something's wrong and throw codes? I'm hoping there are some OBD knowledgeable people here to give me some insight. My gut feeling is that a modern OBDII engine and harness by itself is not a standalone unit. I have a feeling that harness needs to hook up to other things such as the gearbox, instrument panel, etc... any ideas?

[Eric]

It all depends on what engine/tranny you plan on using. Gm LS series engines can easily ($$$$) be re-programmed to ignore engine lights, I'm not sure on the Ford stuff as I don't get alot of requests to wire them but the ones I have done have just been using the same tranny that came with the engine. If you are using a manual tranny, get an engine ecu that came out of a manual car. Stuff like traction control will set ecu codes so find an ecu that was on a car without it. Also, alot of OBD II cars started using immobilizers of some sort. They are easy enough to deal with, just get the control unit, receiver and key all at the same time. If you are more specific about what engine you plan on using, I can give you some more pointers. As for wiring it, if you have patience and a wiring diagram, it is not too bad, if you have neither, let me know, I'll see what I can do.

[Kalun D]

2 things that will make it difficult.

The catalytic converters, there's not much room for them and mufflers also.

The EVAP system is complex, you can't vent the gas tanks directly to the atmosphere.

I would think you could make a different transaxle work, you don't have much choice when it comes to midengine. As long as the computer was for manual shift.

[BillE]

Chris Ford has a complete package for the 4.6 it is a retro fit for earlier mustangs We have the parts you will need to mate it to the tyranny

[Chris P.]

Ford 4.6? OK - I will admit - I'm not up on American engines.

Bill - Would this be a later model Mustang engine that is also used in earlier ones or a crate motor? It sounds like if I were to use one, there wouldn't have to be any recalibration and I could mate it up to an Audi tranny without the computer throwing codes - is that right?

Eric - I don't have any idea what engine I'm using now because I know squat about OBDII. I don't want to pick up an engine and then find out that there is no way to use it without throwing codes because of a different tranny, weight of car is drastically different, etc... plus I don't have the benefit of doing any serious work on the engine but I guess I won't get picky.

Thanks for your input and patience...

[Ron Earp]

Chris,
You'll find Ford's 4.6L (D)OHC V8 in all sorts of cars and trucks. In auto Crown Vics, Mustangs (man and auto), Trucks (man, auto, 4wd), Vans, etc. It is the same basic thing as the 5.4L (D)OHC motor found in trucks, vans, and the new GT. There are stock Ford supercharged versions of both as well.

But to be honest, if I were you and designing a car from the ground up, with the intent to sell to a market, I'd use a GM SB, one of the late model ones. Lots more tuning support, smaller package than the mod motors, and more power with the expection of the blown 4.6L and 5.4L motors.
Ron

[Eric]

There is no motor that can't be used, it is just a matter of what you need to get with it. And I agree with Ron, GM's new LS2, all aluminum, DBW throttle, individual coils, over 400 hp, and is available for about $7000 CANADIAN new, I dont think you could build an engine for that, but if you go that route, you also need alot of peripherals like wiring, harness etc, easier to just buy a used LS1 from a corvette or camaro and get everything you need with it.

[Lynn]

Chris,

My car has an EEC-IV (Ford) management system, so I have some experience along these lines although it is not OBD-II. As mentioned, as long as the EMS you use was designed for a standard transmission, there should be no issue, BUT you will still need to provide load/no load inputs to the computer. I used a pressure switch on the clutch and fabricated position sensensing switch that is closed when the transaxle is in neutral. These inputs are in OR logic so that if either is "on", the computer knows there is no load on the engine (I am sure you will find that this is universally required.) In terms of the engine itself, you will have to implement the sensors required in one way or another if you plan to have the car's emissions checked by an OBD-II based test system. In the case of NC, custom/homebuilt cars are exempted from emissions testing. However, the only things that I did not implement were the airpumps and, of course, the catalytic converts (to which the airpumps connect.) The purge solenoid and charcoal canister for the tank vent were not difficult with my system. My point is that, even if it's not required, you can still make your drive train as clean as possible.

You will have to do quite a bit of research and study to either marry your chassis harness to the factory engine/computer harness or build your own harness from scratch. I found it easier to do the former. (In doing so, I actually found an error in the Ford circuit diagrams for the WOT A/C cutoff.) The biggest issue you will have is physically fitting the various devices in an already cramped engine bay. You may want to see if Oregon will give you the option of actual emissions testing (sniffer) vs direct reading from the OBD-II EMS system. With some engines, I have been told that it is quite possible to achieve legal emissions levels without every single device that was on the original car if a little tweaking and programming is done. Remember that manufacturers are striving for fleet emissions numbers, as well as, individual model emissions, so sometimes devices are used to help this overall fleet rating and may not be required for the individual engine type.

What is absolutely maddening about all of this is that, often, if you use a '60s engine, on which emissions wasn't given a second thought, everyone is happy! That is totally stupid if the goal is really to clean up the air. To me it is far better to be cleaner (while maybe not exactly to current specs) than to just pollute at will. But, that's just me. The Aussies have very strict requiements in this area, so maybe some of our brethern from down under can help. (Bye the way, even California exempts the first 500 kit/custom cars to be registered each year. At least, I think that's the right number, but you get the point.)

Regards,
Lynn

[Chris P.]

Wow - lot's of responses and good information - thanks. Oregon is telling me that they will title a scratch built car (which is not a replica) with the year it is completed and title assigned, and emissions testing will therefore by default will have to be OBDII. It's beginning to sound like it may not be as bad as I was thinking. It's obviously not going to be a simple install and drive off situation, but at least it looks like the stock computer / programming can stay the same. Boy NC sounds nice... damn, haven't been planning on moving though... sure would make this project a whole lot easier... Hmmmm... or maybe I should make a 330P4 replica... no emissions on that baby...

[Mark Scrivener]

Hey Chris,

what did you wind up doing? Any good info to share?

There are others of us out here who would just as soon be smog compliant if possible without undue cost or performance loss.

Thanks,
Mark

[TimB]

There were also OBDII complian 302's used in some late model Fords.....my wifes 01 explorer for example. Ford EEC V can be easily reprogramed with the right software package. My current daily driver has been reprogrammed to accept a F150 Lightning mass airflow sensor and ACT sensor, a M112 blower and 30# injectors using this

http://www.sctflash.com/main.php

There are many parameters this allows you to do yourself and if you want some real custom application stuff like I have they can email you a tuning file to upload

[Chris P.]

I still have not reached that part of the design / build yet. Things are not moving lightning fast at the moment - all I have so far is a tranny and a steering rack. I would have wheel bearings / hubs / brakes by now if I could figure out what I'll be able to use. Vette part prices are beyond ridiculous, unless I get lucky on eBay.

Anyway, I'm not at the engine quite yet. I figured I'd make my body pieces first, then build the frame to fit inside it - that seems easier then the other way around. At the moment, I'm running different ideas on the bodywork in CFD software I have at work. When I'm happy enough with that then I'll start to make the body buck. (I forgot - I need to pick up a windshield this weekend...)

As soon as I find out anything more on adapting OBDII engines, I'll be sure to let you guys know. As years go on, more and more of us will probably have no choice. Just hope OBDIII doesn't sneak in to soon on us.

Tim - that kind of thing could be real handy to me if it would allow me to reset parameters to keep error codes from popping up. That's my #1 concern. As long as I can get it legal and titled, then I'm on my way to tuning. Thanks for the link - I'm going to read up on that and ask them some questions.

[TimB]

Chris it can definitely be used to turn parameters on and off. A common one that is disabled is the downstream O2 sensor that verifies the car has CATS or disabling the egr function so you can remove the egr valve without a code. The company was founded by a former Ford powertrain engineer and he has access to parameters that other tuners can only dream about.

[Hershal Byrd]

Chris,
RF has built a few with all of the smog requirments. OBD II
systems are available as well. I believe the Australian ADR's are tougher than most American States.

Hersh [img]/ubbthreads/images/graemlins/smile.gif[/img]