I have a 75 f-150 with a 360 and a c-6 automatic tranny. I have ordered my 390 engine from advance auto parts along with most all other parts I think I need. The mechanic I talked to today told me that there is a lot more to it than just swap them out. He said that I would need a new torque converter, radiator and a few other things and that the 360 and the 390 did not have bolt holes in the same places and that things off the 360 would not bolt up correctly to the 390. The reason that he said that I need a new torque converter is that the new motor will have more power and the motor will burn the tranny up if the converter has the incorrect stall speed. Any truth? Is he full of it?? I bought the 390 v-8, edelbrock performer intake, performer carb #1406, new dizzy, cap and rotor, new plugs, wires, coil, starter, starter soleniod, motor mounts, water pump, thermostat and housing, valve covers, air cleaner, fuel filter, new gaskets for all things needing one, and an oil pan. All I did not buy is an air conditioner compressor, alternator, and headers. Hopefully, I will get some headers here soon. I'm trying to do a little homework on the headers. Do you guys think that this will be a problem to do? I have some mechanical knowledge, but, not enough to try to do the swap myself. ANY help or ideas would be very comforting after buying all this stuff. Thanks. :+

Also, on the valve covers, both have holes in them. I know that one is for the oil fill. What is the other one for?? The PCV valve or just crankcase ventilation or what. Thanks again for reading this long post.

 

The mechanic is full of it. The 360 and 390 are EXACTLY the same on the outside except for the notch in the crank flange which means absolutely nothing as far as interchangeability goes. The torque converter will be the same and the flywheel will be the same. If this is the mechanic who is doing the work he is just trying to get more money out of you or he knows nothing about the FEs.

 

Thanks for the reassurance. I had thought that all things were the same. I am just talking to a few guys about doing the work right now. This guy i'm talking about will not be getting my business. Thanks again. Does the set up I have chosen sound like a decent one? I have read a lot of posts on this site and tried to do my homework. I am looking to get a dependable ride and one that has a little more power than the 360. Thanks again. Sean.

 

I think you will really like your new 390. If you don't care about looks flowtech makes headers for your truck for about 100 bucks. They fit my truck perfectly and don't leak when I use the hooker gaskets that they recommend. I tried the gaskets edelbrock recommended and even though they port match perfectly they leak like crazy.

 

I have power steering on my truck. Will the flowtech headers clear power steering and other stuff that's down there? Sean

 

Well my '70 has power steering so I think it will. I believe that the headers are the same for both of our trucks but there is a chance they have a different set for the '75.

 

Question. I have found the flowtech headers on a web site where they are ceramic coated for $294. I hear the ceramic coating is a good thing to have. Is it really worth the extra $190? What do you think? Sean

 

Also, would a copper gasket be better than the other types of gaskets?

 

I would suggest that you also buy a Pertronix Ignitor kit and the Flamethrower coil to convert that distributor from points to electronic ignition, unless the distributor you said you bought for the 390 is already electronically controlled.

In terms of the headers, where do you live? If you're in the desert, I don't know that the ceramic header coating would be worth much. If you have any exposure to moisture, however, the ceramic coating will make them last a lot longer. In that case, $200 is cheap insurance.

The holes in your valve covers are for crankcase ventilation and oil fill. You can get by with just putting a PCV-valve equipped cap on one and using a standard cap on the other.

 

hey 75 explorerxlt what did you pay for your 390? just the motor not all the extras? im looking for a fresh motor for my truck and i completely forgot about advance.

thnaks

 

To back up what Rat said "The mechanic is full of it." Everything that cna bolt to a 360 will bolt to a 390. They are usually from the same casting. So why wouldn't they interchange. The only thing I was wondering was what cam are you using? The stock or an after market. What after market if an aftermarket? That will have more of an effect on your torque converter than the extra HP. The cam profile, ramp, duration, and lift have more to do with the converter selection. All the above information if high enough will require a high stall TC in order to ge the Vehicle moving more easily. I hope this helps on that part of the equation.

Also the combo you are using sounds like a good setup. What "dizzy" are you using. Is it a stock rebuild from a major auto chain or a new unit from mallory or MSD unit?? If you are using the stock rebuild, the pertronix conversion would be highly recomended. Along with the Flame thrower coil.

The headers canbe had for nearly any price ranging from $99- $450+. And the ceramic coating is good in some situations.


Scotty

 

 

$1199.00 + 250.00 core charge which I just got back last weekend. It runs good. It looked really good when I bought it. Everything clean and tight. I have about 300 miles on it so far and all is well. For an extra $99.99, you can get an extended warranty that will take it up to 36 months with unlimited mileage.

The parts covered are:
the engine block, cylinder heads, crankshafts, camshafts, connecting rods, pistons, piston rings, bearings, timing components, rocker assemblies, valves, valve springs, push rods, lifters, oil pump, freeze and oil gallery plugs. Factory installed seals and gaskets are covered for the first 15 months of operation. That was taken from the warranty sheet itself. I hope this helps.

 

Also, basically everything is stock except the intake and carb. Distributor is from a big chain. No problems. She runs good, so why go and change(break) something! This is a daily driver and so far so good. About 10 1/2 miles per gallon on the first tank of gas I kept mileage on.

 

hey that aint bad. i might go that rout sometime here in the future, but ill see if i cant work out the kinks in the one i got with out pulling it. thanks for the reply.