FE or FT?
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From: waco
FE or FT?
I have a 73 SWB F100. I had a 390 in it for a while and came across a good deal on a 460 so I made the swap. The 460 is good....but it's just not an FE. I used to be a realy hard core Chevy guy until I helped a friend put a rear main seal in his 360. From the moment I got the oil pan off of that 360 and saw the main cap design....I knew I had to have one, and I've been a Ford guy ever since.
I have 3 core motors to choose from to build the 460's replacement. I have a 360, that is parts as far as I'm concerned. I have a 390 that came from a 73 pick up. I also have a 391. All this leads to questions.
Would the 391 or the 390 be a better choice for performance?
If I go with the 391, can I put regular pick up heads and manifold on it?
The 391 has a welded "C" on the rear of the block. Ive never seen that before...what does it mean?
Any other comments and all information welcomed.
Thanks,
Doc
I have 3 core motors to choose from to build the 460's replacement. I have a 360, that is parts as far as I'm concerned. I have a 390 that came from a 73 pick up. I also have a 391. All this leads to questions.
Would the 391 or the 390 be a better choice for performance?
If I go with the 391, can I put regular pick up heads and manifold on it?
The 391 has a welded "C" on the rear of the block. Ive never seen that before...what does it mean?
Any other comments and all information welcomed.
Thanks,
Doc
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From: Iowa
Interesting. You've got enough parts to build quite a good FE. How good depends on what your priorities are and how much you want to spend.
The FT 391 is a little different than te FE 390. There are a lot of little differences that you dont see immediately. Such as, on the 391:
1. Heads are small port low flow high velocity to promote low end torque
2. Exhaust crossover is in a different place
3. Cast iron timing cover
4. Distributor hole is bigger
5. Oil pump driveshaft is bigger
6. Forged steel externally balanced crank
7. Low compression pistons, possibly 4 ring
8. Smaller valves
9. Crank snout is bigger
10. Rear crank flange is thicker
11. Heavy duty block with a higher strength alloy and extra main reinforcement
12. More head chamber volume for low compression
Basically they're truck motors. The crank can be used in an FE if you have the snout remachined to FE size, the rear flange thinned to FE size, and have it internally balanced. It makes a very good bulletproof crank.
The block can be used if you get a bushing for the distributor hole. DSC sells 'em for $26.
The heads and intake manifold are matched sets (FE intake must be used with FE heads, and FT intake must be used with FT heads). Unless you're building a torque / mileage motor with the smallest possible cam, use the FE parts.
Dont use the pistons out of any of 'em, when you get the block bored over you'll need new pistons anyway.
The rods are the same from the 390 and the 391. Use whichever ones are in better condition. I would suggest the 391 rods, since they most likely led an easier life in a low compression low revving motor.
So the question becomes... What are your priorities for this build? Mileage? Power? Torque? How much of all 3? How many cubic dollars do you want to spend on this? Good, fast, cheap: You can pick any two.
The FT 391 is a little different than te FE 390. There are a lot of little differences that you dont see immediately. Such as, on the 391:
1. Heads are small port low flow high velocity to promote low end torque
2. Exhaust crossover is in a different place
3. Cast iron timing cover
4. Distributor hole is bigger
5. Oil pump driveshaft is bigger
6. Forged steel externally balanced crank
7. Low compression pistons, possibly 4 ring
8. Smaller valves
9. Crank snout is bigger
10. Rear crank flange is thicker
11. Heavy duty block with a higher strength alloy and extra main reinforcement
12. More head chamber volume for low compression
Basically they're truck motors. The crank can be used in an FE if you have the snout remachined to FE size, the rear flange thinned to FE size, and have it internally balanced. It makes a very good bulletproof crank.
The block can be used if you get a bushing for the distributor hole. DSC sells 'em for $26.
The heads and intake manifold are matched sets (FE intake must be used with FE heads, and FT intake must be used with FT heads). Unless you're building a torque / mileage motor with the smallest possible cam, use the FE parts.
Dont use the pistons out of any of 'em, when you get the block bored over you'll need new pistons anyway.
The rods are the same from the 390 and the 391. Use whichever ones are in better condition. I would suggest the 391 rods, since they most likely led an easier life in a low compression low revving motor.
So the question becomes... What are your priorities for this build? Mileage? Power? Torque? How much of all 3? How many cubic dollars do you want to spend on this? Good, fast, cheap: You can pick any two.
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Joined: Oct 2004
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From: CT
The welded or sandscratch "C" on the back was common to the 428 CJ/SCJ blocks. You sure it's a 391? It could be a 428 CJ block someone stuffed a 391 crank into. I'd be taking a better look at that block. Look for the "428" inside the water passages on the deck or inside the center freeze plug on each side. While your inside the block see if a 13/64" drill bit shank fits between the cyl wall cores. Also measure the cyl bore for a 4.13 bore keeping in mind overbore. If these all check out your looking at a 428 block. Is that crank out of the "C" block a cast iron of forged steel? Iron will have a parting line running down the from the mold. Forged will be smooth. The 391's came with a forged crank standard. Look for a IU, IUB or IUA for a 428 crank and C4TE-B or G, C6TE-C or E, C7TE-B, D2TE-EA for the 391 forged cranks. G.
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From: waco
Rusty 70, I want to build for mileage with a heavy emphasis on torque. I don't care a bit about the horse power. I'm in a squared off heavy truck. Horsepower won't move it like torque. How would it work to use the 391 block, with the internals, and externals 390? Would I gain any real torque by putting a 428 crank in it? I'd like to get about 450 pounds of torque at around 10 MPG. I'm not sure what combination to use. I've never seriously built an FE.
FFR, It is definately a 391. It has different heads and intake than a refular passenger car FE. They aren't different by much....but they are different. It has FE valve covers, and the FE bolt patern for the bell housing. It definately has a welded "C" on the rear of the block to the right. It's a big "C" maybe 4 to 6 inches tall. The motor is completely together right now, so I can't give any specifics. It did come out of a grain truck. There is a tag riveted to the side of the block that says a place from Dallas Texas rebuilt it at one point. On the tag it says the block is over board .60, the rod and main journals are under cut by 10. I'm not sure what crank is actualy in it. I would like to use that heavy truck block for my build. It has the big ribs running down the out side of the block.
Doc
FFR, It is definately a 391. It has different heads and intake than a refular passenger car FE. They aren't different by much....but they are different. It has FE valve covers, and the FE bolt patern for the bell housing. It definately has a welded "C" on the rear of the block to the right. It's a big "C" maybe 4 to 6 inches tall. The motor is completely together right now, so I can't give any specifics. It did come out of a grain truck. There is a tag riveted to the side of the block that says a place from Dallas Texas rebuilt it at one point. On the tag it says the block is over board .60, the rod and main journals are under cut by 10. I'm not sure what crank is actualy in it. I would like to use that heavy truck block for my build. It has the big ribs running down the out side of the block.
Doc
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From: Iowa
Well I'll tell ya, my high(er) performance 390 in my '70 F100, I recently got 17mpg on a trip. Hot-rodding it around town gets about 10mpg though. Admittedly, this is with a Holley fuel injection system. However, the motor was most definately NOT built for mileage. You should be able to duplicate my results with a motor built for mileage and a carburetor. 10 might be a good number for a 460, but FE's can do better if you know what you're doing.
First, you will gain torque by putting a 428 crank in it. However, you will also decrease mileage. Personally, I dont think it's worth spending the money. Here's how I'd build the motor, considering what you have already:
1. Perform the FT block modifications I listed above. It should go another .020" to 4.130", or 428 bore size. Most FT blocks do, but have your machinist check it for current bore size and sonic check it to make sure it will take another overbore. If it wont take another overbore safely, you've got a 360 block that might actually be a truck block. Most 360 blocks were converted FT blocks.
2. Dont use the FT crank. For what you're doing, the 390 crank will hold up just fine. Using it will save a lot of money on machining. Besides, it's almost bulletproof in it's own right.
3. Edit: Never mind, see #7.
4. 391 rods.
5. We'll figure 10cc for the valve relief volume in the pistons you're going to get.
6. Pistons could be an issue, depending on your final bore size. For now, we'll figure a .030" over 390, with .012" of deck clearance. (this is how mine came out)
7. Another question: Is the FT intake manifold a 2 barrel, or a 4 barrel? If it's a 4 barrel, then I recommend you use the FT heads and intake, along with a smaller Holley 4 barrel carb. Something like a 500cfm 4 barrel would be good. Be sure to port those FT heads so that they'll flow at least a little air. FT heads were very restrictive, but do promote good torque and mileage.
8. Use .018" thick steel shim head gaskets. This will result in .030" quench area, with excellent detonation resistance.
9. With the above components, including the FT heads, you should have close to 9.3:1 compression, depending on final combustion chamber cc's.
10. Use a Crane 343901 cam, to promote good torque.
11. Use headers. Stock exhaust manifolds suck, even for a torque setup like this.
12. Adjustable valvetrain setup to replace the non-adjustable setup. Allows accurate lifter preload.
According to desktop dyno, you'd have 432ft-lbs @ 2000rpm, and an even 300hp @ 4500rpm. Of course, that hp number is dependant on the porting done to the heads. Unported, it would be more like 250hp @ 3500rpm. Should get you excellent mileage.
Just an idea I cooked up off the top of my head. Let me know about the intake manifold, the heads, and on the actual bore size of the FT block. Yes, you'll have to start tearing stuff apart. Have fun!
First, you will gain torque by putting a 428 crank in it. However, you will also decrease mileage. Personally, I dont think it's worth spending the money. Here's how I'd build the motor, considering what you have already:
1. Perform the FT block modifications I listed above. It should go another .020" to 4.130", or 428 bore size. Most FT blocks do, but have your machinist check it for current bore size and sonic check it to make sure it will take another overbore. If it wont take another overbore safely, you've got a 360 block that might actually be a truck block. Most 360 blocks were converted FT blocks.
2. Dont use the FT crank. For what you're doing, the 390 crank will hold up just fine. Using it will save a lot of money on machining. Besides, it's almost bulletproof in it's own right.
3. Edit: Never mind, see #7.
4. 391 rods.
5. We'll figure 10cc for the valve relief volume in the pistons you're going to get.
6. Pistons could be an issue, depending on your final bore size. For now, we'll figure a .030" over 390, with .012" of deck clearance. (this is how mine came out)
7. Another question: Is the FT intake manifold a 2 barrel, or a 4 barrel? If it's a 4 barrel, then I recommend you use the FT heads and intake, along with a smaller Holley 4 barrel carb. Something like a 500cfm 4 barrel would be good. Be sure to port those FT heads so that they'll flow at least a little air. FT heads were very restrictive, but do promote good torque and mileage.
8. Use .018" thick steel shim head gaskets. This will result in .030" quench area, with excellent detonation resistance.
9. With the above components, including the FT heads, you should have close to 9.3:1 compression, depending on final combustion chamber cc's.
10. Use a Crane 343901 cam, to promote good torque.
11. Use headers. Stock exhaust manifolds suck, even for a torque setup like this.
12. Adjustable valvetrain setup to replace the non-adjustable setup. Allows accurate lifter preload.
According to desktop dyno, you'd have 432ft-lbs @ 2000rpm, and an even 300hp @ 4500rpm. Of course, that hp number is dependant on the porting done to the heads. Unported, it would be more like 250hp @ 3500rpm. Should get you excellent mileage.
Just an idea I cooked up off the top of my head. Let me know about the intake manifold, the heads, and on the actual bore size of the FT block. Yes, you'll have to start tearing stuff apart. Have fun!
Last edited by rusty70f100; Jun 17, 2005 at 11:53 PM.
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From: waco
Rusty 70 F100,
I'm lucky enough to have the FT block, but not lucky enough to have it with a 4 barrel. It is a 2 barrel manifold, with a little motorcraft on top. I'm pretty sure it's not a regular 360 block because of the big ribs running down the side. My 360 and 390 both have smooth sides. The FT block has (I think) 3 ribs that are maybe an inch wide running from just under the heads to just over the oil pan.
One more question: I saw on another web site where a guy took a regular 390 block and bored the cylenders completely out of it. Then he put 427 sleeves back in. I called my machinest earlier today, and he said the only draw back is I would have to have the block decked. He told me to get all 8 holes sleeved would run me right around 450 bucks. If I did something like that, and used the FT steel crank....it should be a screamer. What is your opinion of boring a block that far and sleeving it?
Doc
I'm lucky enough to have the FT block, but not lucky enough to have it with a 4 barrel. It is a 2 barrel manifold, with a little motorcraft on top. I'm pretty sure it's not a regular 360 block because of the big ribs running down the side. My 360 and 390 both have smooth sides. The FT block has (I think) 3 ribs that are maybe an inch wide running from just under the heads to just over the oil pan.
One more question: I saw on another web site where a guy took a regular 390 block and bored the cylenders completely out of it. Then he put 427 sleeves back in. I called my machinest earlier today, and he said the only draw back is I would have to have the block decked. He told me to get all 8 holes sleeved would run me right around 450 bucks. If I did something like that, and used the FT steel crank....it should be a screamer. What is your opinion of boring a block that far and sleeving it?
Doc
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From: CT
Hey Doc was that Wes Adams "Poor mans 427" buildup on the net54 forum? Pretty cool stuff. Hope she runs good for him and should be finished soon hopefully. The 391 cranks have a 1.76 snout vs the std 1.36 FE. Anyway that block is a good find. George Anderson at Gessford machine did one of these years ago without much success. G.
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From: Creedmoor, North Carolina
Originally Posted by FFR428
The welded or sandscratch "C" on the back was common to the 428 CJ/SCJ blocks. You sure it's a 391? It could be a 428 CJ block someone stuffed a 391 crank into.
I'd be taking a better look at that block. Look for the "428" inside the water passages on the deck or inside the center freeze plug on each side. While your inside the block see if a 13/64" drill bit shank fits between the cyl wall cores. Also measure the cyl bore for a 4.13 bore keeping in mind overbore. If these all check out your looking at a 428 block. Is that crank out of the "C" block a cast iron of forged steel? Iron will have a parting line running down the from the mold. Forged will be smooth. The 391's came with a forged crank standard. Look for a IU, IUB or IUA for a 428 crank and C4TE-B or G, C6TE-C or E, C7TE-B, D2TE-EA for the 391 forged cranks. G.
I'd be taking a better look at that block. Look for the "428" inside the water passages on the deck or inside the center freeze plug on each side. While your inside the block see if a 13/64" drill bit shank fits between the cyl wall cores. Also measure the cyl bore for a 4.13 bore keeping in mind overbore. If these all check out your looking at a 428 block. Is that crank out of the "C" block a cast iron of forged steel? Iron will have a parting line running down the from the mold. Forged will be smooth. The 391's came with a forged crank standard. Look for a IU, IUB or IUA for a 428 crank and C4TE-B or G, C6TE-C or E, C7TE-B, D2TE-EA for the 391 forged cranks. G.
John
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From: Creedmoor, North Carolina
Originally Posted by rusty70f100
Well I'll tell ya, my high(er) performance 390 in my '70 F100, I recently got 17mpg on a trip. Hot-rodding it around town gets about 10mpg though. Admittedly, this is with a Holley fuel injection system. However, the motor was most definately NOT built for mileage. You should be able to duplicate my results with a motor built for mileage and a carburetor. 10 might be a good number for a 460, but FE's can do better if you know what you're doing.
First, you will gain torque by putting a 428 crank in it. However, you will also decrease mileage.
First, you will gain torque by putting a 428 crank in it. However, you will also decrease mileage.
I saw my first FT block last week opened up by a big time FEer. Together we couldn't see any big difference in the FT over a FE block (standard issue). We know there are some fatter blocks over standard.
If it aint exotic yall can't post about it. An out of the box fresh 390 is one heck of a motor, torque oozing. If the docster aing rolling in the dough, he can still have one strong pulling engine.
How much do you have invested in your engine to get 17 mpg?
I'd like to see it more real here and fun on FE.com.
my 2
John
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Hey FFR428,
Yep, that's me that's doing "The Poor Mans 427"! I didn't know that word of mouth got this far LOL. I hope it works LOL. I've just started posting on "The Poor Mans 427" again! I have sooooooo much to post on that it will be a little bit before I'm done with the engine. We still need to gather up some parts to complete the project. But I'm glade that Doc is asking Q's about it from others. Take care
Wes
Yep, that's me that's doing "The Poor Mans 427"! I didn't know that word of mouth got this far LOL. I hope it works LOL. I've just started posting on "The Poor Mans 427" again! I have sooooooo much to post on that it will be a little bit before I'm done with the engine. We still need to gather up some parts to complete the project. But I'm glade that Doc is asking Q's about it from others. Take care
Wes
Last edited by Ford428CJ; Jun 18, 2005 at 09:08 AM.
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From: waco
8 to 12 MPG may be the norm for a 390, I think that's shooting a little low.
17 MPG may be possible with a 390, I think that's shooting kind of high....actualy, real high.
I do know for sure that on my last 390, I did a stock rebuild with an RV cam, added a duraspark distributor, MSD ignition module, headers, and Edelbrock performer manifold, and dual 2 1/2" pipes. The truck would pull a house down with ease and got 12 MPG in town and 14 MPG on the highway. The funny thing was it got the same fuel mileage no matter how I drove it.
FFR 428, Wes Adam's build up was what I was talking about. It would take me 2 or 3 months to duplicate that engine due to budget constraints, but I'm in no hurry and I think it would be well worth the wait.
I would like to run a combination by ya'll to get opinions:
391 block bored and sleeved to a 427, 428 crank, 391 rods, heads from a 390 engine hogged out for the C/J valves, Edelbrock performer RPM manifold, headers, and that 343901 cam, not sure about pistons yet but shoot for a 9 to 1 - 9.5 to 1 C/R.
I want another FE so bad I can taste it, but bear in mind....I currently have a 460 and no matter what you do there is no replacement for dicsplacement and I don't want to loose all my cubes. Going back with a good stout 390 rebuild is good....but it's 70 less cubic inches.
FFR 428, where can I get more information on that 391 build that you mentioned earlier? I've built some pretty wild chevy motors....but nothing much more than stock for a Ford. I don't mind spending the money for an engine (with in reason) but I don't want to spend a bunch and have a dog or worse yet blow up on the first trip out.
Thanks for all the replies. All the information has been realy informitive.
Doc
17 MPG may be possible with a 390, I think that's shooting kind of high....actualy, real high.
I do know for sure that on my last 390, I did a stock rebuild with an RV cam, added a duraspark distributor, MSD ignition module, headers, and Edelbrock performer manifold, and dual 2 1/2" pipes. The truck would pull a house down with ease and got 12 MPG in town and 14 MPG on the highway. The funny thing was it got the same fuel mileage no matter how I drove it.
FFR 428, Wes Adam's build up was what I was talking about. It would take me 2 or 3 months to duplicate that engine due to budget constraints, but I'm in no hurry and I think it would be well worth the wait.
I would like to run a combination by ya'll to get opinions:
391 block bored and sleeved to a 427, 428 crank, 391 rods, heads from a 390 engine hogged out for the C/J valves, Edelbrock performer RPM manifold, headers, and that 343901 cam, not sure about pistons yet but shoot for a 9 to 1 - 9.5 to 1 C/R.
I want another FE so bad I can taste it, but bear in mind....I currently have a 460 and no matter what you do there is no replacement for dicsplacement and I don't want to loose all my cubes. Going back with a good stout 390 rebuild is good....but it's 70 less cubic inches.
FFR 428, where can I get more information on that 391 build that you mentioned earlier? I've built some pretty wild chevy motors....but nothing much more than stock for a Ford. I don't mind spending the money for an engine (with in reason) but I don't want to spend a bunch and have a dog or worse yet blow up on the first trip out.
Thanks for all the replies. All the information has been realy informitive.
Doc
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From: waco
Ford 428,
I'm pretty srious about giving it a shot and I'm gathering up all the information possible. I called my machine shop yesterday and asked about machine work that wild....and they thought it would work, but did say the block would have to be decked...just like you had said. They also said that a sleeved block should be better than a factory block. I think I may have to find out.
Doc
I'm pretty srious about giving it a shot and I'm gathering up all the information possible. I called my machine shop yesterday and asked about machine work that wild....and they thought it would work, but did say the block would have to be decked...just like you had said. They also said that a sleeved block should be better than a factory block. I think I may have to find out.
Doc
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where is DSC?,i could use a dist bushing you mentioned for my 330ft to use a different dizzy,do you happen to know where to get a flexplate with a weight to bolt up a c6 behind the 330ft,the external balance issue has been a real pain to address for my c6 swap.
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From: Klamath Falls OR