This is my first time on here hoping to get some good advise.
I have a 1979 F-150 with a 400m (stock), C-6, 7-inch lift, and 35 inch tires. This will also be the first engine that i have tried to beef up. Have pulled and put a new one but never anything beyond that. It is basically a truck to drive in the winter and go off roading with. It seems to lack the power when im in the mud. Don't have a ton of money to spend but want to get some more power out of it. Was thinking of headers, new intake, carb, cam and having the heads machined. I heard something that the timing for the 400m was junk and should just get new stuff. Any suggestestions would great.

P.S. im also looking for chrome nerf bars and 38x14.5x15 tires for it at a reasonable price.

Thanks

 

Well from my stand point what rearends gears do you have in your truck now. The reason it's slugish could be dew to the wrong gears, and your looking to put 38" mudders on that's going to make it even more of a slug off road. Your going to have to swap out your gears for some 4.88 or even higher with those big meaty tires on there.

Just my 2 Cents

 

What gears are you running? You can have a bad a$$ motor, but if you have the wrong gears it will make the motor seem weak. With 36" tires I would at least run 4:11 gears and if you go to 38" tires I would go 4:88 gears. That would wake a truck up. On the other side 4v intake and carb is almost a must. If you going to change cam a timing chain is a must and buy a good 3 key way timing set to get rid of the cam retard. I did these mods plus close to 10:1 comp and a 2000 stall converter. Next I want to lift, bigger tires and better gears.

 

Hey shazam I must have been reading your mind or a much slower typer either one.

 

Thank you everyone for your advise. First off i would like to remind everyone that im a rookie thats why im coming to your guys for your advice. I don't know what kind of gears are in my truck, whatever was stock. I also was looking at the summit catalog and saw that a timing chain gears and all that were only $100 chea[er than a Pete Jackson Gear drive. Was wondering if i would just be better to put the gear drive it. If you have any other suggestions besides different gears on what parts or brand name parts to use i could sure use it.

 

I personaly like a true double roller timing chain set for about $40.00 that what I put in.

 

the first thing i would due is to swap in a steeper set of gears. dollar for dollar that would be the best place to start. you want 38's then i agree with shazam and 79 f-150 go with at least 4.56's minimum. if you want more power off road then go even steeper. but one thing to keep in mind the steper the ratio the weaker the pinion shaft becomes due to having fewer teeth. some might disagree with me. something to keep in mind if your contemplating a big power build on the motor.

now for the engine. i'm not completely sure on the heads. i've been told by numerous people the 400 heads can't be ported on the exhaust side due to the water jacket popping up into the exhaust port. i don't know for sure i haven't done this on a set of heads yet. gonna find a set that's cracked to find out for sure. the 4v intake is a definite, right along with the 4 barrel carb. the pete jackson gear drive is a toss up. i wouldn't use one on a low rpm motor. also with the gear drive machining is sometimes required to make it fit, so your eating up money you could put somewhere else (like a set of roller rockers). i would just use a good roller chain and gears. as for the cam you should probably go with a dual pattern favoring the exhaust side, by this i mean more duration. headers are another toss-up, some like the stock manifolds, some like headers. depends on your preference. but i will say this if you by headers, buy a set that have been jet-hot or ceramic coated. i know their expensive but they will last alot longer than a cheap set espeicially offroad.

anyway enuff of my rambling if i think off anything else i'll let you know.

later......

 

 

Listen to these guys, they know what there talking about. first thing you need to do is to look at your dif tags to find out what dif ratio's you have. If your gears are to tall it will make your truck slugish. Larger tires also make the final ratio even taller. Ford was fairly good about puting shorter gears in 4x4's but cheak. I know from experiance how much tall gears suck. I just droped my 500hp monster in a 2wd f-150 with a c-6 and a ford 9" rear end. My rear has 2.75 gears in it! Unless you like to go 70 or 80 in first gear tall gears suck! Tell ya whats funny is when one of those chevy guys with there big hoped up 4x4's wants to race and they beat my monster off the line (becous first final gear ratio is 6)and I then go zooming ahead. I hear them shift four times and you should see the look on there face when I go zooming ahead and I havent even shifed into second yet. Of course I gota slow down and stop befor I hit third becous I would be going so fast my tires would explode. Anyway find out your gears and then deturmine your RPM range for your engine. 1000-5000 is typical and good for a 4x4. Then pick your gears acording to what you build your engine for. One more tip. Pick your cam first then design the engine around that.

-Jim