Thanks for saying that, I didn't know that, and my thoughts would have been useless.

mgundry, did you swap computers, or are you still running on the six cylinder computer? The computers are behind the drivers side kick panel, and the plug on the computer goes through the firewall to the harness. You definitely can't run a V8 on a I6 computer - that will cause all sorts of problems. About the harness - I'm certain it is integrated, since it is a '92. What part of the harness did you trade out with the swap?

 

We have a new computer, or atleast one for a V8, but we have yet to put it in, due to failure to locate the computer, but we found it now, lol . In the swap we used the V8 harness for all the connectors and hook-ups on the V8. but we left all the other harness wires the same (like for everything else under the hood that is not on the engine. the harness that goes through the firewall is the origianal). about the computer that we do have, no-one is %100 sure it is the right one because I did not match it with a calibration number, I just narrowed down my options till I came to this computer. It is for a 1994 302 v8 4x4 manual. my truck is a 92, but the engine is a 94.

 

There is a list of calibration codes on http://fordfuelinjection.com if you want to try to find it. Mine's not on that list, but maybe you'll have better luck. I would go through the computer wiring harness and double check that pin locations match the V8 computer. If any of the V8 harness didn't match up with the stock I6 harness, it would show up when you check the pinout for the new computer.

 

Sorry for asking... but when you say check pin locations, are you just saying to make sure that the pins match up with the harness, and the V8 computer? Thanks for that URL, it has alot of helpful info on there.

 

Yeah, each pin is numbered in the computer harness, just go through and make sure the locations of each input/output is the same between the two computers. The plugs are all the same, but some of the wires might have different locations on one opposed to the other. I don't know for sure, but it would probably be wise to make sure all the sensors connect to the computer where they are supposed to.

 

Thanks for the help so far. I will not be-able to start work on my truck again untill probably Monday. Do you think I will be-able to put the clutch and pressure plate from the 300 on the 302 flywheel? If so then that would be great. This is a ways down the road... but I heard that if the O2 sensor is not hooked up correctly it can really mess things up, i have headers to put on so where should the O2 sensor go to get complete readings?

 

The O2 sensor should mount as close to the engine as possible. Do you have full lenght headers? It should be pretty easy if you have shorty headers, you could mount the O2 sensor in a location very similar to stock. With full length headers, I've heard of people running the O2 sensor in the collector of one header, which would only read air/fuel ratio of one bank of cylinders. It works, but it's definitely not ideal.

 

I found the computer behind the left kick panel, it is a ways back there, what would be the easiest way to pull it out? My headers are full length. If I put an equalizer pipe right after the headers, then do you think I could stick the O2 sensor there?

 

while it seems a bit odd to only sample one bank of cylinders, it should be fine. Most factory systems are like this, and barring something strange happening, the banks should be pretty much equal. I'm MUCH more used to/knowledgeable about GM EFI, but mounting in a collector should be fine. On the GM system, if you change to headers you have to change to a heated O2 sensor, but all of the Fords I've seen have heated sensors already, and they are usually mounted in the downpipe. As to the clutch, everything will bolt up if the disc is in backwards, and underneath a vehicle it's an easy mistake to make. My truck currently has a master cylinder, clutch disc and pressure plate for a 94, transmission and bellhousing from an '81, throwout bearing, fork, and slave cylinder for an 86, with a homeade bracket for the slave. (not really homeade. My brother is a machinist, so I drew him a diagram and he milled it out of aluminum.) and it all works OK. When I was researching it though, I just used AutoZone's website and compared part numbers for different vehicles. All of the different engines usually called for the same part number. The only differences seemed to be related to the different schemes for actuating the clutch. i.e. the mechanical linkage took one part number regardless of engine, the external slave linkage took another, and the internal slave yet another. Many years crossed over if you looked up the disc only. Apparently in the kits the only difference was in the throwout bearing setup. Measuring three different discs and pressure plates every way I could think of showed that they were all essentially the same. As to your harness question, the Haynes manual wiring diagram show sthe same for I6 or V8 except the distributor. I do know that on a GM the same computer is used with V6 or V8, and only the program in the chip need be changed, although that's on a TBI. I've never honestly looked to see if the Ford system was sequential or batch fired. I would think that it was batch fired, and if so, then it would stand to reason that everything is the same. If you don't change the number of cylinders parameter in the chip then it would throw the computer off, making it sense a different RPM than actual. It might run like this, but not good. Again, my information is based partially on what research I've done, and experience with GM systems. I'd really love to see someone who has dealt with the Ford system chime in and correct anything I may be mistaken about.

 

Unless things have changed Ford is batch fired.
Was a Chev guy for a while.

 

The computer is held in by one clamp at the back of the case under the dash. Take out the clamp and then pull the computer towards the inside of the truck to get it out. Make sure that you have disconnected the harness on the other side of the fire wall before pulling it out. The tricky part is getting the new one in with the rubber gasket around the plug. I found that going around the end of the rubber seal with duct tape and having someone on the engine side of the firewall wiggling while someone pushes the computer through from the inside works the best.

200000+F150, I don't think that Ford computers have interchangable chips like GM's do. I'm pretty sure the computer would definitely be thrown off with an extra two cylinders to control. Ford trucks were all batch fire except for mass air trucks which were sequential. As for the harness, I couldn't remember exactly what was different between the two, because there are a couple things different, but I think all the main things are in the same spots. I haven't looked at the Haynes wiring diagram in a while, so I couldn't remember for sure.

 

200000+F150 and EPNCSU2006, thanks for your helpful information and thoughts. To get the clutch to work we used the 302 flywheel with the 300 clutch and pressure plate, works like a charm so far. Next we will tackle the wiring... Thanks