Old_Ironsides
Registered User
Hello,
I just joined the forum recently, since I want to do a thread on my latest project, dropping a 7.3 IDI into my 1979 f150. I have done a great amount of research prior to taking on this project, and since quite a bit of the information I have found has come from this forum, I want to share how this build goes in the hope that it helps someone else considering doing something similar.
Anyhow.. here's some background on the truck. Earlier in the year I purchased this f150 from a gentleman who bought it new back in 1979. When I got the truck, it was in pretty sad shape, on top of which it had been sitting for several years due to a burnt up automatic trans. This was the end of the trucks life for the previous owner, and the condition that I bought it in. By the way, the name the truck was already given when i bought it was "Old Ironsides", so that is where my username and the name in the thread title have come form. What the truck is exactly is a 4x4 with a 351M, C6 auto, married NP205 transfer case, a ford 9 inch out back, and a high pinion dana 44 up front. Here's a picture of it as it was when I first got it.
Not very impressive looking... and although the body is pretty well rusted out (besides the bed, although it doesn't match lol), the frame and rest of the chassis is in excellent condition. The first thing I did when i got the truck was to source a good c6 trans for it, and got it running well. Then it over the next few months it got a complete brake job, new tires, and other miscellaneous parts to make it a safe and somewhat reliable driver. I then finally did something about how ugly it was, and painted the whole truck one color... It isn't fancy, and was done with a paint brush, but it doesn't look too bad from a ways away.
This is how i drove it for a while, and it was running pretty well, though even with a rebuilt carb and whatnot, it still had issues running well all of the time. The engine was pretty tired anyway, since this truck used to travel around with a slide in camper. This truck even went to Washington state twice from here in CT according to the gentleman i bought it from, so it has certainly been well used. On top of this, I couldn't afford to keep driving it very much at the 6-7 mpg it was getting....
And that is what brings me here... since i made the decision to pull out the old 351M and c6, in favor of a 7.3 IDI and ZF5. This obviously started by me sourcing a good used engine and transmission, and i was lucky enough to find one locally from a great guy that was parting out a badly rotted 1989 f350.
I did hear this IDI run and was able to make sure the transmission seemed alright since the setup was still in the truck when I went to go look at it a few weeks before picking it up. Once I had the engine, transmission, clutch assembly, etc that i bought back home, it was time to start taking my truck apart.
And just like that, It is down to bare frame rails to start the measuring and modifying that needs to be done to get the IDI slid back in there. I started out by taking the transmission and seeing how it sat on the old mount for the auto, and how far off it was.
From where it is sitting in those pictures, it needs to go back a few inches, so some clearance may need to be cut into the cab. The way i am approaching this build it to locate everything off of the transfer case mount, so that in the end the t case will be back in its original position, and i should not have to do anything as far as lengthening and shorting drive shafts. I don't think this will be too difficult to accomplish, since the overall length of the ZF5 is only 1/4" longer than the C6. To locate the transmission where it needs to be, i decided to use the newer style trans mount that is much smaller, and easier to re mount on the cross member. The bigger greasy mount in the picture is the one from the C6 that will not be used.
After carefully measuring and remeasuring and measuring one more time to be sure i was where i needed to be, i laid out the marks on the crossmember and grabbed the drill, with a final bit size of 1/2" and drilled the two new holes for the transmission mount.
And this is as far as i have gotten so far on my conversion. Next is going to be to remount the transmission in the new location, and to figure out where new motor mount towers need to be fabricated. I plan on posting updates as I go through this project, and I hope everyone enjoys!
I just joined the forum recently, since I want to do a thread on my latest project, dropping a 7.3 IDI into my 1979 f150. I have done a great amount of research prior to taking on this project, and since quite a bit of the information I have found has come from this forum, I want to share how this build goes in the hope that it helps someone else considering doing something similar.
Anyhow.. here's some background on the truck. Earlier in the year I purchased this f150 from a gentleman who bought it new back in 1979. When I got the truck, it was in pretty sad shape, on top of which it had been sitting for several years due to a burnt up automatic trans. This was the end of the trucks life for the previous owner, and the condition that I bought it in. By the way, the name the truck was already given when i bought it was "Old Ironsides", so that is where my username and the name in the thread title have come form. What the truck is exactly is a 4x4 with a 351M, C6 auto, married NP205 transfer case, a ford 9 inch out back, and a high pinion dana 44 up front. Here's a picture of it as it was when I first got it.
You must be registered for see images attach
Not very impressive looking... and although the body is pretty well rusted out (besides the bed, although it doesn't match lol), the frame and rest of the chassis is in excellent condition. The first thing I did when i got the truck was to source a good c6 trans for it, and got it running well. Then it over the next few months it got a complete brake job, new tires, and other miscellaneous parts to make it a safe and somewhat reliable driver. I then finally did something about how ugly it was, and painted the whole truck one color... It isn't fancy, and was done with a paint brush, but it doesn't look too bad from a ways away.
You must be registered for see images attach
You must be registered for see images attach
This is how i drove it for a while, and it was running pretty well, though even with a rebuilt carb and whatnot, it still had issues running well all of the time. The engine was pretty tired anyway, since this truck used to travel around with a slide in camper. This truck even went to Washington state twice from here in CT according to the gentleman i bought it from, so it has certainly been well used. On top of this, I couldn't afford to keep driving it very much at the 6-7 mpg it was getting....
And that is what brings me here... since i made the decision to pull out the old 351M and c6, in favor of a 7.3 IDI and ZF5. This obviously started by me sourcing a good used engine and transmission, and i was lucky enough to find one locally from a great guy that was parting out a badly rotted 1989 f350.
You must be registered for see images attach
You must be registered for see images attach
I did hear this IDI run and was able to make sure the transmission seemed alright since the setup was still in the truck when I went to go look at it a few weeks before picking it up. Once I had the engine, transmission, clutch assembly, etc that i bought back home, it was time to start taking my truck apart.
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
You must be registered for see images attach
And just like that, It is down to bare frame rails to start the measuring and modifying that needs to be done to get the IDI slid back in there. I started out by taking the transmission and seeing how it sat on the old mount for the auto, and how far off it was.
You must be registered for see images attach
You must be registered for see images attach
From where it is sitting in those pictures, it needs to go back a few inches, so some clearance may need to be cut into the cab. The way i am approaching this build it to locate everything off of the transfer case mount, so that in the end the t case will be back in its original position, and i should not have to do anything as far as lengthening and shorting drive shafts. I don't think this will be too difficult to accomplish, since the overall length of the ZF5 is only 1/4" longer than the C6. To locate the transmission where it needs to be, i decided to use the newer style trans mount that is much smaller, and easier to re mount on the cross member. The bigger greasy mount in the picture is the one from the C6 that will not be used.
You must be registered for see images attach
After carefully measuring and remeasuring and measuring one more time to be sure i was where i needed to be, i laid out the marks on the crossmember and grabbed the drill, with a final bit size of 1/2" and drilled the two new holes for the transmission mount.
You must be registered for see images attach
You must be registered for see images attach
And this is as far as i have gotten so far on my conversion. Next is going to be to remount the transmission in the new location, and to figure out where new motor mount towers need to be fabricated. I plan on posting updates as I go through this project, and I hope everyone enjoys!
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