I have good 1970 390 in my truck, but I need more power, if i port my heads, add a cam, aluminum intake, carb, headers, stall converter.
Will this give me the snap I am looking for or should I put in a crate motor or what, looking for enough power to put down rice burners, camaros etc.

 

if you add all that you should be pushing close to 370hp, thats plenty to show them ricers whos boss, let us know if you want a parts list. good luck

 

Sure. Are you doing a complete rebuild, or just adding parts looking for a wakeup?

If you're looking at a stall converter, you may not need one. *most* FE cams wont need one. The stock will work just fine. Now if you get real wild on the porting and the cam, then yeah, but most likely you wont.

Are you looking for recommendations on the cam? We can certainly give you those, but first how can you spend on it? For the basic 390, the going thing is the Crane 343901 cam. It'll provide a good HP increase over stock and provide some great torque off the line. There are roller cams available like the 349521, which provide great increases in HP, but Gtex has had some problems with his valvetrain, and I'd let him get it sorted out before ordering one.

I'd also suggest the installation of CJ size valves while you're in there, just to let it breathe a little better.

 

well the motor has low miles and runs good, I am wondering if the bolt ons will give me the power I want or should I put the green into a built 390 from a ford site.

 

Anything you can do to let it breathe. I think you're on the right track. For now, I'm going to recommend the Crane 343901. The Crane 343941 is another option, but may be a little harder on valvetrain parts due to it's increased lift. If you get heavy duty rocker shafts then go with the 941 for a little more hp.

Definately get the heads ported. That will probably help more than anything.

Personally, I will never buy a motor built by someone else unless it came from the Ford factory, and even then I have my doubts. But if you trust 'em and have the money, go for it. Just post what they've got into it and the price so we can tell you if you're getting taken.

 

Why are the lifts on cams so different from stock? I don't have my book here to compare, but a stock cam i was interested in was like 548/440 and these Crane cams are both in the mid to high 500s. Is there a good place to get some base line information on cams?

 

cam explanations

Very good site for info on learning/understanding how a cam works.

 

Here's my take on the FE cam issue in a truck. If you are wanting to have a hot street truck, then you are going to have to make some compromises in towing and gas mileage. Here's why.

The average suggestion will be to use a fairly mild cam in a truck, so you keep your low end torque. But I haven't seen a well built 390 yet that wouldn't smoke the tires easily off the line, and often times more that just one gear. So, what does this tell me? That we have more torque than we need at the bottom end. Now, it we feather the throttle we can control the wheelspin, but I'll bet the Civic in the other lane aint featherin' his throttle! The other problem with this is that after we get rolling a little and can give it full throttle we run out of breath at 4500 to 5500. Which in my mind means we have put all our eggs in the low RPM basket, where we have more than enough already!

The solution, in the world according to Scouder, would be to use a little bigger cam, more duration, so that we intentionally soften up the low end torque, but as we get rolling the engine starts to come into it's power band right where we need it, and we still have plenty of breath left to run it right up into the 6000+ RPM range.

I've heard truck guys for years, including this board, saying that they did real well in a drag race at first, but then got passed. Aerodynamics suck. But if you have any chance to overcome it where should your power be? More low end? (I'm making a raspberry sound). No. Wouldn't it make sense to move the torque peak up the powerband so we can use it against wind resistance, instead of running at half throttle down low to prevent tire spin?

Finally, the crappy part about this solution is that you do have to port the heads, use a strong valve train, increase compression and suffer with poor mileage and towing. But, your question was if you could beat the ricers at their game. Yes, but last time I checked it was the finish line that mattered, so if they go past you on the top end guess what they are gonna be telling their buddies? Kicked the crap out of another old pickup. Went by him like he was standing still.

Let the flaming begin.

-Scouder

 

/asbestos suit on, and sparking up the flame thrower... .

5500 with 4.10's 29" tall tire and 3rd gear of 1:1 is well over 109mph.
109mph with traction should put an F100 short bed into the 12's, and an F250 long bed into the low 13's.
I see nothing shabby about that.
Drag racing is all about getting out of the hole.
If you can pick up 26-27mpg from the 1/8th to the 1/4 it doesn't mean much if you're only going 60mph at the 1/8th.
over 80% of your acceleration is should be done by half track if your rig is set up right. We have monster tq, lets utilize it.
Areodynamics is crappy, but weight is more our enemy than that. To overcome weight, you need grunt.
Worry'n about what our rigs do from 5000-6000 seems to be signing up to ricer mentality (no offence... /ducking...)... Nothing I like better in my stock Mustang than beating a car that runs 114mph with my measly 104mph.
This is the beauty of a torque-y V8... get out of the hole, charge hard, and see what the rice-a-ronie has to try and make up for it...

/backing very slowly out of the room...
/looking over shoulder...
we're all friends here right?




right?

 

I see your point. BUT, they are already spinning the tires out of the hole. So they have two choices. One, get the truck to hook up so they can use the torque they have. Two, move the torque curve up the scale.

Since hooking the truck up is going to be very difficult without major dollars and suspension work, why not resolve the tire spin issue while at the same time throwing more HP at the aerodynamics problem. After all, if they are already spinning, reducing low end is not going to slow them down. In fact, elimnating tire spin (all else being equal) will improve ET.

I realize that a drag race is typically won or lost in the first 60', and to some extent you are supporting my argument. If they are spinning the tires out of the hole what happens to their 60' times? FLUSH.

Ring the bell, round two!

-Scouder

 

Oh yeah, by the way. Thanks for the response. I was starting to think nobody was going to bite!

-Scouder

 

Would this mean that a smaller motor, like a 360 vs a 390, would be better for drag racing? I mean, the heads wont run out of wind as soon, you can wind it up higher in a particular gear without the hp and torque dropping way off. DD2K shows, all other things being equal, that a 360 slightly makes more HP than the 390. I'd think that this would be an advantage in a drag race.

Scouder, are you thinking Crane 349521 roller cam? I know I am.

 

O.K. a little more info, and thanks for the help so far this is a 1970 F250 the motor has low miles and was well taken care of I am the third owner first two only used the truck for hauling stuff around no towing, I have a thread going about the c-6 in the tranny forum trying to get it to shift harder or its coming out to get built I will try the black stripe vacuum mod, shift kit and band adjustment first, now this truck isnt going to see alot of towing etc. I was thinkin of running 4.11 to 4.56 gears also, not worried about highway crusin just street light bruisin, now will bolt ons and motor work get me where I want, or should I start sving for a build or crate motor, no this isnt going to be a funny car but I would like to show all the misguided youth out there why there is no replacment for cubic displacement, yes there is always somone faster, and money is an object so I am looking for bang for the buck. like I said it is a beast now for a single exhaust and huge bias ply tires, but not fast enough yet.
Thanks for the help I will let you all know what I go with, after I get some more info from yall.

 

how much do you want to spend then we can lead you in the right direction heres a parts list id go for:

edelbrock performer intake
holley 600cfm carb
DUI dizzy
headers
free flowing dual exhaust

and if you want to go further get a crane 901 cam and lifters, it all depends on how much you want to spend.

 

Actually, if it were my engine, with the idea of light to light street racing, I would like to see just a little more duration than that. The problem is that the 349541 is maybe just a hair too big for a 390. I think a cam with a max RPM of about 6500 (using cranes specs) would be perfect.

-Scouder