Ford F834 Posted January 30, 2018 Author Share Posted January 30, 2018 As of 1987 through 1989 all the F-series trucks used the same fuel pump, regardless of engine. I don't know how many psi that is, but there isn't a diff between 6 and 8. But after 1989 I don't know. (There's that need for a 1990+ catalog again.) As for the diff between SD and MAF, my understanding (I haven't done it) is that if you are going with a fairly stock engine that SD works fine. But I'm not sure I agree with the extra complexity statement. Yes, there are more pins in the connector, but you don't really need all of them as you don't need all that much more in the way of I/O. Both take the same # of O2 sensors w/o a cat - one on the six - although with a cat the MAF can use two. And there's the four or so wires to/from the MAF. Plus six wires to the injectors instead of two. But, other than that there's not much difference. And with MAF you are set for whatever changes you want to make. Another difference is in the use or not of a power distribution box/center. Bill can tell us, but somewhere between 1990 and 1995 they introduced the power center that sits on the driver's fender. I think the it is a good thing, but it does require a few changes in the electrical wiring to accommodate it. And it is the combination of power distribution center and style of EFI that can make it a bit more tedious to find the donor vehicle. In other words, up to some date the trucks will be SD but w/o PDC. Then from that date until the change to MAF they'll be SD and PDC. After that date they are MAF and PDC. I'm not trying to talk you into anything, but I am trying to get my head, and yours, around the options. Thanks for the input Gary. Maybe he is making the crank position sensor out to be a bigger deal than it is... I don't know him or his background, he was just offering casual advice based on the information I gave him. This is why I posted here to get other input. I still wish I could buy up the sefi specific parts, but buying a major system of parts like that can be a gamble at my junkyards. Some workers want to charge like crazy for every nut and bolt and strand of wire, while others are almost too lazy and under charge. I figure it evens out, but if I pulled the efi and got a stickler scaling my cart it could get insanely expensive. I wouldn't get around to installing it for some time, and if any of it was bad my warranty would be long over. I hate to miss an opportunity but I think I need to keep my focus here and save EFI for another day. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 30, 2018 Share Posted January 30, 2018 Thanks for the input Gary. Maybe he is making the crank position sensor out to be a bigger deal than it is... I don't know him or his background, he was just offering casual advice based on the information I gave him. This is why I posted here to get other input. I still wish I could buy up the sefi specific parts, but buying a major system of parts like that can be a gamble at my junkyards. Some workers want to charge like crazy for every nut and bolt and strand of wire, while others are almost too lazy and under charge. I figure it evens out, but if I pulled the efi and got a stickler scaling my cart it could get insanely expensive. I wouldn't get around to installing it for some time, and if any of it was bad my warranty would be long over. I hate to miss an opportunity but I think I need to keep my focus here and save EFI for another day. That makes perfect sense. Trust me, I really need to heed that advice. As for the crank sensor, if the 300 is like the 460, that sensor is not needed. From what Bill and Adam have told me, and I've read it elsewhere many times, the distributor provides all the crank-positioning info the PCM needs. But, I don't know for sure that that is true for the 300. Link to comment Share on other sites More sharing options...
Ford F834 Posted January 30, 2018 Author Share Posted January 30, 2018 That makes perfect sense. Trust me, I really need to heed that advice. As for the crank sensor, if the 300 is like the 460, that sensor is not needed. From what Bill and Adam have told me, and I've read it elsewhere many times, the distributor provides all the crank-positioning info the PCM needs. But, I don't know for sure that that is true for the 300. Is this where I envoke the childhood dare: "you first!" Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 30, 2018 Share Posted January 30, 2018 Is this where I envoke the childhood dare: "you first!" Bill doesn't have the crank sensor on Darth, although he's asking Mark to watch for one there in CA. And I won't have it on Big Blue nor Dad's truck - which will also use a 460 dizzy. So the real question becomes if the 300 dizzy is like the 460's, and probably that of the other V8's. The #1 pin or arm on the reluctor is more narrow than the others, so the computer knows when it goes by and sets the engine timing from there. Link to comment Share on other sites More sharing options...
85lebaront2 Posted January 30, 2018 Share Posted January 30, 2018 As of 1987 through 1989 all the F-series trucks used the same fuel pump, regardless of engine. I don't know how many psi that is, but there isn't a diff between 6 and 8. But after 1989 I don't know. (There's that need for a 1990+ catalog again.) As for the diff between SD and MAF, my understanding (I haven't done it) is that if you are going with a fairly stock engine that SD works fine. But I'm not sure I agree with the extra complexity statement. Yes, there are more pins in the connector, but you don't really need all of them as you don't need all that much more in the way of I/O. Both take the same # of O2 sensors w/o a cat - one on the six - although with a cat the MAF can use two. And there's the four or so wires to/from the MAF. Plus six wires to the injectors instead of two. But, other than that there's not much difference. And with MAF you are set for whatever changes you want to make. Another difference is in the use or not of a power distribution box/center. Bill can tell us, but somewhere between 1990 and 1995 they introduced the power center that sits on the driver's fender. I think the it is a good thing, but it does require a few changes in the electrical wiring to accommodate it. And it is the combination of power distribution center and style of EFI that can make it a bit more tedious to find the donor vehicle. In other words, up to some date the trucks will be SD but w/o PDC. Then from that date until the change to MAF they'll be SD and PDC. After that date they are MAF and PDC. I'm not trying to talk you into anything, but I am trying to get my head, and yours, around the options. For all of you, Ford introduced the PDC to the trucks starting in 1992 with the introduction of the aeronose body. This is also the point where the PCM was moved slightly to the right from the 1987-1991 location in a recess in the left air box. The chassis to dash harness interface was also revamped. Up though 1991 the rear chassis harness plugged into either the dash harness (1980-1986) or the front harness (1987-1991). Starting in 1992 the rear harness has a dedicated plug on the firewall that goes into the dash harness. As a result, when looking down next to the left end of the firewall there are 3 plugs, in order outside to inside, 60 or 104 pin PCM, 76 pin Front harness, 24 pin? rear harness. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 30, 2018 Share Posted January 30, 2018 For all of you, Ford introduced the PDC to the trucks starting in 1992 with the introduction of the aeronose body. This is also the point where the PCM was moved slightly to the right from the 1987-1991 location in a recess in the left air box. The chassis to dash harness interface was also revamped. Up though 1991 the rear chassis harness plugged into either the dash harness (1980-1986) or the front harness (1987-1991). Starting in 1992 the rear harness has a dedicated plug on the firewall that goes into the dash harness. As a result, when looking down next to the left end of the firewall there are 3 plugs, in order outside to inside, 60 or 104 pin PCM, 76 pin Front harness, 24 pin? rear harness. Good info, Bill. Need to figure out how to capture this kind of stuff. I have harnii from Huck (1990), the '95 that Jim parted out, the '96 that Ray sent me, and the '96 that Mark got in CA. So I have a bit of a progression in both PDC's and in batch/SEFI. And having some place to turn to the 'splains it with pictures would certainly help when the time comes to do the deep dive and start teasing out the wires I need and those I don't. Link to comment Share on other sites More sharing options...
85lebaront2 Posted January 30, 2018 Share Posted January 30, 2018 Good info, Bill. Need to figure out how to capture this kind of stuff. I have harnii from Huck (1990), the '95 that Jim parted out, the '96 that Ray sent me, and the '96 that Mark got in CA. So I have a bit of a progression in both PDC's and in batch/SEFI. And having some place to turn to the 'splains it with pictures would certainly help when the time comes to do the deep dive and start teasing out the wires I need and those I don't. You have an excellent resource in your hands, the one I used, 1996 EVTM. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 30, 2018 Share Posted January 30, 2018 You have an excellent resource in your hands, the one I used, 1996 EVTM. Well, "in my hands" might be an overstatement - I let it get 2' away for a bit. But, its brother should be here any day and then yours will wing its way back to you - along w/some other bits and bobs. Yes, it is an excellent resource, and unless we create the definitive how-to EFI your 460 on here, I think it is required reading for doing the job. However, it doesn't explain what the other years have in the way of PDC's, connectors, etc. And the info you provided re that also helps significantly. One reason for that is trying to tell the potential EFI'er why they need to pick "stuff" from this particular year, or years. Link to comment Share on other sites More sharing options...
Ford F834 Posted January 31, 2018 Author Share Posted January 31, 2018 So I am reading that if you EFI a 300, you really want to switch to the EFI cylinder head because the compression ratio and swirl chamber are what the system is designed to work with. According to my machinist these have thinner casting and are somewhat prone to cracking as EFI runs leaner/hotter, so you want to have it checked/mangafluxed before using one... then there is the block. EFI blocks have a threaded port for a knock sensor. You can fab something for this on an early carb block, but it's another thing to do. I have to say the whole project sounds more like one should just do an engine swap rather than update a carb engine. Link to comment Share on other sites More sharing options...
Gary Lewis Posted January 31, 2018 Share Posted January 31, 2018 So I am reading that if you EFI a 300, you really want to switch to the EFI cylinder head because the compression ratio and swirl chamber are what the system is designed to work with. According to my machinist these have thinner casting and are somewhat prone to cracking as EFI runs leaner/hotter, so you want to have it checked/mangafluxed before using one... then there is the block. EFI blocks have a threaded port for a knock sensor. You can fab something for this on an early carb block, but it's another thing to do. I have to say the whole project sounds more like one should just do an engine swap rather than update a carb engine. Jonathan - I'm certainly no expert. But, what you are saying about a transplant makes sense given the variables in carb vs EFI engines. This is somewhat similar to the 460 where if you go with the EFI intake/plenums you'll need the EFI heads as the ports are different. And, if you do that you have to use the EFI exhaust manifolds as those ports are different. So, your suggestion of transplanting an EFI engine makes sense as then you don't have to worry about the differences. Link to comment Share on other sites More sharing options...
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