Tbi research

"Ok guys, i know ive brought t

"Ok guys, i know ive brought this up before but i wanted to inform those of you that dont know, and those that would like to know. been doing my home work for a while now before i start my boat project of swapping a chevy 1990 model tbi in place of a carb 260 mercruiser.
First of all i was wrong with what i had said in a previous blog,You can not find a o2 simutator for a tbi engine, there is no such thing.
what you do do is get a harness made and a chip along with it which specificaly made to your application, it excludes the o2 sensor, the egr and the knock unless you want them. Im guessing the set the engine to run off of the temp instead of the o2 in the exhaust. the result, a engine that probably doesnt adjust as much, but is still better than a carb.
the harness is $225 and the chip for it is $95
web site is"http://www.affordable-fuel-injection.com/tbi-wiring-harness.htm" they will tell you what ecm you need from gm.
There is a list of other items you need. I know this is going to be quite a project, but it is doable. any questions or comments are welcome.
also do you really need the big water fuel separator filter that is on the 260 mercruiser????"

"What are you using for the ma

"What are you using for the main harness fro the ECM, sensors, etc? I wouldn't recommend just getting a bunch of terminals, crimping them on and calling it good. It will need to be water resistant (nothing is totally waterproof) and unless the right crimper is used, they won't work well. I'm only asking because it wasn't stated. I suspect that this application is really for cars, right? You're also going to need to add some relays and as was mentioned in the other thread, some way to kill the fuel pump in case the motor stops. It's easy enough to do but it needs to be in place and in the marine ECM programs, the RPM signal from the distributor being absent will cause the ECM to interrupt the trigger to the fuel pump relay.

If you have the right harness, you can use a commonly available ECM, made by Delphi. Then, you need to program it. That way, you won't need anything to simulate an O2 sensor since the pre-'07 marine motors don't use one anyway. You do, however, need a knock sensor (the KS module is internal on the newer ECMs). Since the Delco distributor with the IC module built in is controllable via the ECM, the timing is pulled back in 5º increments if there's any detonation picked up by the knock sensor and assuming the base timing is set correctly (10º BTDC, for marine apps in Indmar motors), the total advance will normally be 35º. If the motor runs hot, the air temp is high and the air is very dry or the fuel octane is too low (or all three), not having a knock sensor could very well kill your motor.

Re: the separator- how much crap do you want getting into your injectors?"

I assume all this claptrap wil

I assume all this claptrap will be USCG approved for marine use? Sure it will!

Jeff

"Jeff, I just wonder what'

"Jeff, I just wonder what's really going on with the mixture by eliminating the o2. Its been a few years, but i think by lowering the temp sensor reading, the system will interpret that the engine is in "warm up" mode thereby enriching the mixture (significantl) and disregarging the O2. Seems a little crude. just thoughts..."

"If the ECM is programmed to s

"If the ECM is programmed to see an O2 sensor and doesn't, it sets a fault code. If the program doesn't need one, there's no problem. The mixture won't be controlled to the degree that it would be if there was an O2 sensor but it will still run fine for a long time as long as the ECM is programmed to run without one. The fuel table will be adjusted according to the normal operating temperature range, set during development of the program. Some of the new motors have an actual warm-up cycle, where the ECM won't even allow high RPM operation until normal operating temp is seen and the only thing the ECM does in that case is leave the fuel/air mix richer than when it's warmed up. When the ECT reading is too low (out of the normal range, i.e below freezing or zero), the ECM throws a code. If the ECM is supposed to see an O2 sensor, it never disregards it, it just makes sure that the amount of O2 in the exhaust is correct for the temperature, MAP (or MAF), throttle position and timing.

The marine applications didn't use an O2 sensor or catalytic convertor. until this year. They work fine without it but they are programmed as "open loop" systems, not "closed loop", like the ones with the O2 and cat.

As for crude- it's in a boat, not a car or truck and the emissions guidelines aren't as stringent as land-based vehicles but they're catching up. EPA and C.A.R.B. are making it necessary to run boats a lot cleaner than ever before."

"guys if you check out the web

"guys if you check out the web link i attached in my first post, the company is offering this harness and chip for a marine application. im not crimping ends or making a harness from scratch! Just check out the site before you go posting stuff. As for the ecm, it runs on what ever the chip tells it to do. thats what the company does on the site i described up above. they provide a Harness, a chip and tell you what ecm computer you need to run with it, its all designed for a marine appliction. they program the chip for what you need, for instance, a boat in the past has been designed without a o2 sensor, so thats how the chip they program for you will be programed.
I dont know how they run without the o2 exactly, but im sure it is much like a carb choke does idleing up when its cold and back down when it warms up. its probably got a more specific set of instructions in the chip and doesn't adjust as much as a normal truck setup would. thats just my guess. You tell me, How are they making efi boat untill 07 without o2 sensors? its gotta work somehow...as for the other sensors i know you need them, was just saying the company can custom make you a harness and chip to your needs. just check out the web site.."

"as for all the cracks about t

"as for all the cracks about the safty and measures that need to be taken and the enviromental stuff. here's what i got to say... i know this is going to be a tuff project especally for the average joe. but i assure you i do very good quality work, all the fuel lines will be high pressure lines set up with a return which means," no rubber lines to crack and leak at all. a flame arrestor will be used, proper connections will be made with fire sealed crimps where needed, a sealed batt box will be used to house the ecm. as for the inviroment. it should be happier, the engine should run cleaner and more efficient. As for coast guard regulations, im not sure on all of them , but its a small boat, i plan on taking out to our mid size lake to do some skiing, not the ocean. and trust me all precautions will be done to make sure everything is secure and working before i go out, cuz i hate breaking down at the lake more than anything."

"Hell to make things easier, t

"Hell to make things easier, the web site i provided even sells complete engines and the hole set up at a fair price. here it is again...http://www.affordable-fuel-injection.com/marine-fuel-injection-systems.htm"

"The O2 sensor only matters as

"The O2 sensor only matters as far as the fuel mixture, not idle speed. The IAC (Idle Air Control) handles that and opens or closes while under way with hard acceleration or deceleration. The ECM is programmed for a specific idle speed and since the throttle plate is almost totally closed at 0º throttle, the idle air has to come from somewhere and the IAC is that somewhere. It's a stepper motor that is told to park itself on key-off and go to a particular setting at key-on. The idle works exactly the same as in a truck since it's a truck motor that goes into marine applications in the case of the GM motors.

The O2 sensor wasn't needed to get the motors to run well in boats but since the emissions numbers are getting tougher, it became necessary to use one (boats were somewhat exempt from meeting emission standards until recently). The other part of the equation is the fact that if you have an O2 sensor AND you want to burn off the combustible exhaust gases, there's usually a catalytic convertor and they needed to come up with a way to get those to live in a motor that squirts water out of the exhaust. I don't think they'll be using an EGR any time soon. I was in Indiana for Mastercraft training in 2000 and there was a motor of the stand in the test facility with an O2 sensor and convertor and that shop had been working on ways to get the system to be as bulletproof as possible.

One thing I can't stress enough is this, from the webpage, near the bottom:

"You will be required to provide your own Coast Guard Approved fuel line and air cleaner for your application. It will be your responsibility to install the system consistent with U.S.G.C. regulations. This system requires a return line to your fuel tank which many of the newer boats already have."

I would call them and ask if the ECM cuts off the trigger to the fuel pump relay if the motor stops and the key stays on. "

You can contact the USCG to ge

You can contact the USCG to get the regs on fuel systems.

"This all sounds good. If the

"This all sounds good. If the ECM is programmed to not use O2 - great. Lots of EFI systems around the world (mexico) that aren't designed to meet stringent EPA and California ARB emissions standards aren't closed loop. My comments about "seems crude" referred to retrofitting a system without recalibration... fooling the system,etc. Good luck."

"If the system comes with an E

"If the system comes with an ECM, they probably have it set for a general range of conditions. The fuel mapping isn't all that complicated and it's done like a matrix. Air, temp, throttle position (actual and +/- delta) all determine the pulse width. They want to make it work for a wide range of applications but they aren't doing anything too tricky."

"Prediction time: Without an

"Prediction time: Without an O2 sensor to tell 'Oz' whats going on, that engine will either run richer than witha carb, or leaner and fry a piston!

Carbs--properly set up--work well for a narrow engine speed/ throttle range--even when compared to fuel injection. Kinda makes one wonder why the engine manufacturers went to them so slavishly, doesn't it? Crusader was the last holdout and, considering that they are the BEST marine engine company on earth--it makes you wonder what they knew!

Jeff"

"Jeff- Look at all of the Merc

"Jeff- Look at all of the Mercruiser, Indmar, PCM, Volvo-Penta and other marine engines in use since late '93 (Indmar's case) or whenever they started using TBI and MFI, then find the ones that had problems due to the calibration. You won't find many. You'll find a lot that had problems from bad maintenance, fuel, winterization and general neglect but not many that ran badly because they were a little rich and definitely not many that ran lean unless it was from the PCV valve going to the #8 runner on the intake. You don't seem to want to believe they did thousands of hours of development design and testing for these motors but they definitely did. I don't know how much the company in the link did but I would think they did a lot, too- otherwise, they wouldn't offer a decent warranty.

Slavishly? I don't know about that. Have you ever talked to a boat owner who didn't have starting issues because of a carb? A motor with no O2 sensor may run a bit rich at times but they'll never develop much power if there's no fuel being delivered, either. Which starts easier- a TBI or a motor with a carb that sits for a few weeks? People want to turn the key and go, not think about how to start the motor. No motor is perfect but injection has cut down on the problems so drastically there's no question that it's a better way AS LONG AS IT'S WELL MAINTAINED. Some people don't want to accept this and some don't want to know how to work on the new motors (I met some of them when I was at Mastercraft training).

Crusader may be the "best engine company on earth" but they still use someone else's motor. Maybe their boats are maintained better than others because the owners know that you can't just let them sit out in the elements and then expect them to be trouble-free. Why are they the best, in your opinion?"