Heloo all I am new here and i have desided to drag out the 71 maverick my dad had in the back yard for about 16 years and start restoring it as a family hotrod. I have a EFI intake from a 85 5.0 truck in which is taller than a car EFI was told they have biger ports and also produse more torq also a AL9 computer from a 89 mustang if i remember right with a superchip installed i have the coversion wiring kit to make the sd harness in to a MAF harness I also have the MAF sincer and housing and a 97 cobra throttle body from a 4.6 belive it or not it bolts right up but will have to make an adapter plate to carry the IAC sincer (Idle air control sincer). So what i was wounding is do you have to run the egr with MAF or can it be block off? here is a list the i thank that has to be hook up MAF sincer injectors Idle air control sincer Throttlebody position sincer fuel pump EGR ? thanks for any help or advice
If your going to retrofit a 302 motor, you need to rewire the computer to injectors to the 302 fire order, settle on a distributer configuration that fits the old block, new fuel lines (2), fuel pump, and a mass air computer to match the type of trans the car has and oxygen sensors placed in the exhaust head pipes. You have quite a job to begin with so stay with stock configuration to start and not try to mix parts until you get the setup running. The truck lower manifold won't fit the car upper half. The battery has to move to the trunk, a larger alternator, new firewall to spring tower braces made and a dozen little details. If you have no previous experience, plan on a long learning curve.
K. Merring thanks for the in put. The 5.0 engine i have is from a 89 crownvictory. I have not strip the engine yet so im not sure if its roller or not yet, it was sd & not maf. I also have the low and upper intake from it also I have the low and upper intake from the truck also and the ports are quite biger than the car intake. I was going to chang my truck to maf thats way i have these parts already but i desides to strip the sd off the truck and go with a carb sence i need some thing reliable to drive so the maverick will be a learning experience sence it will not be a dayly driver. the Maf computer i have is for an auto and going to use an auto trans. also do you have to have the egr hook up? my truck with the efi was on it the egr got stopped up so i unplug it and it run fine with it unpluged thats way i ask. thanks once again
The 89 should be a roller cam motor. The truck intake while bolting up to the 89 ok, will be to high to fit the Mav unless you put some kind of scoop on the hood. The ports are somewhat bigger but don't get rapped up on increased performance. You wouldn't be able to tell anyway. The truck has room under the hood for a longer intake track to help low end pulling torque. The cam was short on timing to also get the lower rpm torque. The truck motor was about done pulling at 4200 rpm. . I would recomend you not try to use the truck intake as it isn't worth the hassle. The Crown Vic motor should pull up to at least 5200 rpm. My Lincoln is speed density and pulls quite hard, a 4000 lb car, so don't sell speed density short on performance in a stock engine. The only difference might be that my Lincoln engine is the HO Mustang engine with SD control.
actually, yes the SD engines will make a few more ponies due to the lack of the Mass-air sensor which creates a bit of a restriction in the intake tract. If two engines are built almost identical, the mass-air engine will usually make less power...but they respond better to modifications. Kind of a catch-22. Everyone says mass-air is better, but if that was the case, why are most aftermarket EFI controllers speed-density type? Always wondered this. Also, if your going to use the engine in stock form, it'd be better to use the EGR. Clean out the throttle body and EGR pipes and use it...gets about 2-3 mpg better mileage, believe it or not. At least my truck does anyway. Good luck
Is Mass Air "better"? Well...the mass air computer is a learning computer and can adapt to changes that affect how much air the motor is getting. The Speed Density computer is preprogrammed from the factory with fuel tables and if things change from factory specs, the tables are no longer valid. That said, I took the EFI harness and parts from an '86 Grand Marquis(and later the upper intake from an '88 T-bird so that the throttle body opening faced the passenger side), and I ran speed density up until earlier this year when I converted to mass air. The motor ran fairly well with SD, but was always running a bit rich...with mass air, that problem has been solved. It also has better idle and better throttle response. I had a special chip burned to address the firing order issue(mass air 'puters are expecting the H.O. firing order) and shut off the thermactor and vapor canister stuff which I do not use. I run the EGR as I have been told it helps with economy. I love my EFI and I think it is worth the effort, but I guess it is not for everyone. I agree with the learning curve...but you always have those of us who have done it at your disposal if you have questions... Why do the aftermarket kits use SD? Probably because it is easier to implement..there are fewer parts and the computer is somewhat less sophisticated. That would be my guess.
Four items. The speed density and mass air still use the same tables. A speed density computer plugged into a mass air car will still allow the engine to start. ....... The difference being, the mass air meter indicates the load where the Map sensor on the speed density is the load indicator. ........ The Mass Air computer only need 4 leads changed to make it handle the 302 fire order. No chips involved. ......... The after market speed density (type) control has no learning ability, no diagnostics and will not change any setting or change a setting to satify any table, except possibly Ox sensor feed back for street use, so what is set up will stay so fine tuning is fully controlable.
Indeed you can switch the injector wires around to make the firing order work out when using a mass air computer with a non-H.O. firing order, but you cannot change the fact that computer will be polling the wrong Ox sensor each time those switched cylinders fires. Will it run? sure. In fact I have read that it doesn't make that much difference and in fact some guys don't bother to change the firing order of the injectors at all and they have claimed that aside from a slightly rougher idle, all is well. Don't get me wrong, you don't need to have a chip burned; I just chose to go this route because I liked the idea of being able to override the emissions equipment that I am not using and also have the firing order/Ox sensor problem corrected all in one shot. I counter the guys who say that speed density is "better"...if it is, why did Ford move away from it and towards mass air as time went on? I have never been privy to the fuel tables programmed into any of the computers, so if they are the same, I stand corrected.
Another thing...I guess it also would make a difference what you want out of the car. My father drag races a Cheby Malibu and runs speed density because it is easier to tune. The car has one purpose in life...wide open balls-out for a quarter mile and then a slow ride back to the pits... I want power, of course, but I am also building a driver and I want better than average fuel efficiency and a smooth idle, etc. Mass air seems better suited for the task. My $.02..er maybe more like $.03 or .$04
You are correct on ox sensors ability to (follow the fire order) which is always after combustion takes place in any cylinder that the sensor see the results of, and tries to correct injection into the next cylinder to fire. Changing the injection from HO to 302 is only half as bad as it seems because all cylinders are not out of phase with the sensor feed back. If a compare is done, it can be seen that only four cylinders donot match up out of eight. To carry on just a bit farther, the reccomended distance for ox sensor location is about 15 " from the exhaust ports. Two reasons for this are to be sure the their operating temperature comes up quickly enough for emmissions considerations, and optimize their response for injection correction of the next cylinder to fire. Unmatched fire order, Ox sensor location do degrade ultimate results but not to the point of causing major engine running problems for all but race situation. I do however disagree with those who put Ox sensors in the collectors of long tube headers. That is pushing the limits of good injection control and timing whether a 5L or 302 is being controlled. Good discussion; your on your way to a good understanding of Ford fuel injection. Now just get Dad to change over to Ford.
To test my understanding some more....if the Ox sensors never heat up to operating temperature(or if they were disconnected altogether), the computer would never get to 'closed loop' and the injector firing order and all of that would be somewhat irrelevant because the computer would be running on fixed tables, right? Then again, if the injectors are not firing in the same order as the spark plugs, there would still be an effect, even if slight. I have recently started thinking that the Ox sensors in my SD incarnation of my project were never functioning at all and that may have contributed to my rich running problem... I had another motive for swapping to MAF. I plan on building a stroker motor at some point and I thought that the SD would probably not react as well as the MAF. Any thoughts about that? I dunno about converting the ol' man to Ford...he worked for GM for 25 years and now has an abundance of parts and knowledge...but he is a car guy in general and he gets into my Ford stuff as well. At least it's not a Ricer, right?(Growing up near the Motor City, I coulda been disowned for that... )
Yes thats right if the sensors don't get up to a temp. of 600*+ they won't work and the computer falls back on fixed fuel tables, asumming there is not wire problen. Most of the tables that have sensor inputs can change up to about 25% +/-. This provides an amazing range of ability to adapt both forward and backward and correct for componant aging, fuel quality, barometric changes and intentional changes as well as reliability. When changing a part or making an adjustment, this has to be relearned by the ECM and takes some 5 miles of driving to happen. People think that making a change shows up instantly next time the engine is started so get fooled into thinking the change made no difference. A code reader should show that the sensors are not working by the codes stored in the ECM. On the 302 conversion, the injectors would be pluged up to follow the ignition same as a 5L would. The computer would not know the difference except for the minor difference in ox sensor phasing. Most don't know that the ECM is that fast and able to track that well. About 93, the ECM processor speed was increased to help all this out.
Another interesting setup is my Kenne Bell super charger operation on my 90 Lincoln speed density. It has it's own special requirements and gets yet into other aspects of operation to be succesful on that kind of engine control. I have done extensive research on setup for this and now have the ability to go from an economy setup to a power setup by finding the limits of each as far as drivability goes.. The next area I am working on is a controllable change over using either an automatic or manuel control assembly. For battle times you understand! This involves a change in ACT sensor locations, water injection and some other items I won't mention for moment until it is worked out. Insturmentation is used to see the results of the changes as well as the seat of the pants dyno and the fuel gauge.
