ok fellas i wanna build up my 390. i want the brake my neck and snap my head into the back window horsepower i crave and the stump pullin' tourque i need fo offroading. and yes this is gonna be a budjet build like 2000-2500 bucks for the whole thing and i just wanna know what all i need to get what i want this is gonna be in my 69 f-250 hiboy which is a daily driver. so any input will be greatly appreciated. my buddy just built his 390 and its a beast and my goal is to have one better than he does since he is my biggest competition and im his and with his 390 he has me one upped... for now atleast. so just lemme know what your sugestions are.thanks


Dustin

 

Personally I would Stroke That beast. Raise the compression too. But that'll eat up a lot of your budget.
Do some head work, but do all of the port and polish yourself if you can in order to save some pennies. Do you already have a carb? headers? manifold? cam? that You can use? I need to know what you already have so I can really suggest some good combos.

Madmike33

 

i can get the headers. and i have the stock 4 barrel intake and carb but i was thinking along the lines of a hollie truck avenger and a performer rpm intake and for a cam i am open to sugestions on that as well thanks

Dustin

 

Allright then if this is a start from scratch build here are the essentials.
Performer Rpm manifold is a good way to go. Headers are a must on an fe. 600 cfm 4 barrel carb is enough for your build although the 670 avenger will be a good pick if you go trailing and hit a lot of inclines. Like I said before head work will really make it come alive for cheap if you do it yourself. If you go for a cam(which is a good idea) you'll more than likely have to get the valve springs done and set up for the specific cam you choose. Last but not least you want to up the piston compression, truck 390s had low compression and that kills you in the HP department.All this minus the valve job should fit in your budget, and make a huge difference.

As for the cam you should use, what will you use the truck for? Like I said before trailing, street, work?

Madmike33

 

It's me, I'm here!

I suggest you do a clone of my build:
1. Performer RPM intake, 700cfm carburetor (I've got the 700cfm fuel injection, and that wont fit the budget)
2. TRW L2291 forged pistons
3. Mr. Gasket .020" thick steel shim head gaskets for more compression and better quench
4. Headers, dual exhaust
5. Crane 343941 cam
6. Fully ported heads. This means completely polish the exhaust, smooth up the intake but leave it somewhat rough, smooth up the intake short side radius, gasket match the intake, clean up the bowls. Better porting = more hp.
7. Adjustable valvetrain and matching springs for the 343941 cam.
8. Roller timing chain, because they're relatively cheap and effective.
9. Melling HV oil pump

The above build, assuming 73cc combustion chambers, will give you 10:1 static compression, and about 8.7:1 dynamic compression. If my motor is any indication, it'll run on pump gas. This is because of the tight quench that the above combination provides.

Desktop dyno says it'll make 417hp @ 5500rpm, and 447ft-lbs @ 4000rpm. If that doesn't snap your neck, I dont know what will.

I've had friends in my truck. When I nail it, they band their head on the back window. It sounds like a mellon.

 

Rusty, what brand of 700 carb and intake are you running? Also what heads are you using? What do you thing of the aluminium Edelbrock heads? Are the c1ae-a or
the c3ae better if they are ported?

 

thanks fellas and i think im gonna go with rusty's suggestions. i appreciate it fellas

 

In order:

Holley 700cfm Commander 950 TBI fuel injection system. Edelbrock Performer RPM intake.
Ported and polished C7AE-A with polished chambers.
Aluminum Edelbrock heads are good, but you cant use the thin steel shim head gaskets with them, so you lose a little compression there. Also, a good porting job on stock late heads, like D2TE-AA, will flow equivalent to stock Edelbrock heads, and cost you a lot less.
Yes, the early heads do flow better and flow like crazy when ported.

7Ford2:
Let us know how it turns out! We like reading good news too! I really think you'll like your new motor. If you have any questions during the process, feel free to ask.

 

If you want to stroke your 390 get a 428 crank from DSCMotorsports $450 that's what i'm doing and with the cam make sure it's a split duration and lift like this as example

316/ 322, Lift .763/ .727 i think mine will will be 266 duration with 663 lift that gives me a nice balance of HP/Torque and still have relibility if you go this route 390 cranks are internal balanced and 428 are external you can use your 390 fly wheel but you'll have to have the crank balanced which can be done by adding the balance onto your 390 flywheel.

 

So Rusty where did you get your holley pro injection kit?

 

A couple of weeks ago i read a article online that An Offroad mag did a test on 4 carbs i believe two from Holley and 2 from Edelbrock which one was the Qjet they tested all 4 on a hardcore wheeler testing on all surfaces up to 65 degree's in every direction and in sand dunes bumps. The Qjet out performed the other 3 in all aspects they had no problems with it. The only thing they did to tune them was to tune them down to 650 rpm or as close to it as possible. If i remember the Qjet was the only one to be able to go that low none of the other 3 couldn't. I plan on using the Qjet on my 390.

 

Jegs, and you know better than to call it the pro-jection.

 

just playing!

 

Yeah I know.

 

My 410 is simaler to rusty's but im running a erson cam.But i use a Q jet carb and wont use any thing else.Im sold.Yea youl have to use a spreadbore adaptor.There about an inch and a half thick maybe two,so it will work like a little tunnel ram.Just tune and jet the carb for your aplacation.