Hey All,
I've got a 69 F250/360/C6/2WD. The 360 is a commercial rebuild (Jasper or such) of a cool service block that the numbers say is one of the best of the best, high nickel content, can be bored/stroked to anything from 352 thru 428, etc. It just started exhibiting a possible/slight knock (sounds like maybe classic wrist pin or cracked piston skirt) at about 80-85 mph on the highway and I've kinda been looking for an excuse to pull it and make it a 390 or 410 but just couldn't justify pulling apart a good running, non-leaking, non-oil burning engine. The real problem around here is that it is not unusual to have to cruise at 70-85 mph to avoid being a road hazard and without any overdrive (even though I run tall 285/75/R16 tires) the engine is "SCCRRREAMIN'" at that speed. I'm pretty sure the engine won't give the ghost anytime soon, and it's not my only driver, so I have time to plan and scheme. If I turn the engine into 390 or 410 it will likely be for a car, (maybe my 68 Mustang) as there is no good trans option, except maybe a Clark, without adaptors, manual or auto for an FE in a truck. So.... I'm looking at what options there are for other engine/trans combos to still have a TRUCK that can pull when I'm done and still be able to keep up on the highway. I'm not necessarily stuck on manual or automatic for the transmission and certainly am aware of the cool factors of a good inline 6 cyl, as well as the gas gulping properties of a 460. I just need to know what stout overdrive transmissions will fit behind the various engine/bell housing pattern families, IE:
>300-6 cyl/302-351-Windsor-I think they're the same?
>FE-I realize not much
>385 series-370-429-460
All Thoughts and wisdom are welcomed.
Thanks,
Gene

 

If you have the money and time, I would personally vote 460 with a ZF and 3.27 gears.

Another combo I personally want is a 300 / ZF with 3.55's.

Ful mileage is going to suck no matter what you do. You can make it suck a little less with higher gear ratios.

I love the 300, but that's just me. I'm not about to compare the 300 and the 460. The 300 is a great truck engine but the 460 has it on sheer size.

They're both great truck engines.

 

Your rear ratio is pretty high, my truck has 3.00s, so at 3,000 rpms I believe it's running 82mph, prancing & pawing out on the big road.

You are used to the power so a mid/late 80s early 90s 460/AOD might be the ticket.





John

 

About the cheapest in the way of trannys is an AOD unit which will have a 6 cyl/small block face pattern. As far as a complete setup, pretty hard to beat a 5.0 Mustang motor with either an AOD or 5 speed setup. There's a pretty good article on this site walking you thru the steps.

Quick Time has a pretty nice selection of bellhousings that will let you put just about anything you want as far as a manual trans behind the FE; an option if you want to go there.

You can go much lower with the rear gearing too; down into the 2s but at that level the towing capabilities aren't too good and you'd really want an automatic setup because it would fry a clutch.

 

My personal opinion, would be to re gear the truck for the highway. 3.00 to 1 would be a good choice, your engine will be under way less strain.

 

Not if it's a 6 banger, that is why they have the higher ratios. Little up front, big in the back.

Big up front little in the rear. Got to have the balance.



John

 

Another option might be to fix the 360 as you plan to, but keep it in the truck and look for a Doug Nash O/D unit that bolts to the back of the C6. These were available as an option I believe behind the 6.9 diesel in the '80's. I've seen a few of them, in fact, my ex-boss has one still attached to the C6 and he said I could just have the whole dang thing. Of course, the tranny won't anything but a diesel (without modification) but I plan to pull the O/D off and see if it fits (with the extension housing) straight onto a non-O/D C6 (depending on the tailshaft length) or if the tailshaft is O/D specific.

I currently have a Gear Vendors unit which I picked up used behind a T19 in my truck, and it really makes a difference in cruise RPMs. With 3.73s my truck is quite happy to cruise at 70-80. Next I'll be going to 3.54s.