Would like some recommendations on what to do with my 390.

Background: I bought a 72 F250 camper special last fall with the intention of pulling our camper and horse trailer (approx. 7-8K lbs). I currently pull our camper with a tow package equipped Expedition (5.4L, 373 gears). It pull it ok but i wouldn't want to pull with anything less. So, I'm wanting this 390 to at least match the power/torque of the 5.4. So, i'm going to need roughly min 120 HP + torque gain.

Current state: Im working on getting the 72 on the road (rockers and exhaust are bad). So, I'm going to have to address the manifold vs header issue quicker than what i was expecting to.

Recommendations: So, i was wondering if anyone had any recommendations for me as to what to do with this 390. My main goal is to get as much early RMP torque as I can get using the stock heads (for now). First phase was starting with installing a RV cam, aluminum intake, 4bbl carb, recurved distributor. I though of replacing the heads maybe next year if it warranted.

So, is my thinking on track for what I want out of this 390 and if i'm keeping the heads stock and not going for overly aggressive HP gains, are headers warranted at this point? Would I see much gain for the $800 i'll be putting out?

Just to be transparent, I've added power steering to the truck and starting on the drum to disk front brake conversion. This truck also has a 373 rear end

Thanks in advance

 

Headers are not really warranted for what you are doing at this time and besides the 3.73 is where you are going to get your low end torque. My 390-2V, with a 3.25 rear in my 65, gets off the line with authority if I desire to really hit the pedal. Stock intake, stock cam, and stock logs.

 

Opening up the exhaust with headers over the restrictive cast iron manifolds is the biggest performance improvement you can make on an FE and will compliment the cam and intake nicely by giving all that air you are pulling in somewhere to go.

 

I agree with Thunderkiss1965 on the headers. Fords are notorious for poor flow on the exhaust side.Mainly valves and ports are too small. But also Look at the manifold on the one side how it exits toward the front angled the wrong way. Terrible design. Headers even cheap ones are a big gain. I have a set of Hedmann Headers I've run since 1997 along with other mods. Biggest problem with the headers is getting them to seal. Run FelPro header gaskets and load up on the Permatex Ultra Copper. Lay the right (passenger side) header in the engine bay before you lower the engine in. bolt up your starter then put the header on. Also get some type of heat wrap for the starter or it will get cooked. This made a HUGE difference on hot restarts. It will also be less load on your battery. Also get some protection for the starter cable. Go with flat top pistons about 9.4:1 used in early T-birds with 390s. Pick a cam for your RPM range but that has more lift and duration on the exhaust side. Mine for example is .484/.510 274°/284° 204°/214° @ .050" lift range is 2500/5500RPM. You'll want something that is smaller that comes on earlier 1500-1800 RPM. I run a Holley Street Dominator with a Holley 4160 600 cfm. It's open plenum but my truck is an f100 and I don't tow anything so I can get away with it on the bottom end. For you go with a dual plane. I also have a windage tray. Definitely use an external trans. cooler if towing. I'd keep your total advance to 34° BTDC at 3000RPM.

 

Do you know it's really a 390? Check the stroke if not.

All 352s and 360s become 390s on sale day.....

 

I've never checked mine but none of the machine shops told me otherwise. It has H in 3rd position on VIN also engine tag is still there. It did have "Camper Special" on the fenders though.It isn't, no wiring. It's an f100 LOL! But you're correct only way to be sure is check the stroke.

 

tbm3, You were on the USS Hornet in 1943?