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I doubt I'm in the right part of the forum, any way about me.
I'm a audi guy , I own 3 of them. Never had a American car in my life.
Well my wife's grandpa died an I got this 1981 ford f150 ranger that also says
Trailer package on the side. It's 2 wheel drive and has a 351m I believe from what
I have read . The truck is very nice her grandpa bought it brand new in 81 an had 88k
On the clock. Very well taken care of. Anyway just wonder what are the first upgrades
I can do for a little more power since it's gutless . Straight bolt on stuff no internals.
It's completely stock. I'm thinking intake manifold an 4 barrel carb and some headers?
Any insight or recommendation would be nice. Just looking for stuff on the cheaper side for now since I do own 3 audis lol
That's a fact!! Lol
You have to have small hands to work on audis , and I'm a small guy haha
I like working on this truck I sit perfect right in the engine bay, there's just so much room to work on everything an it goes by so fast , unlike audi stuff.
I got the truck last night, an replaced the plugs, wires, cap an rotor, fuel filter , air filter , oil, flushed an replaced coolant , replaced valve cover gaskets replaced half the vacuum lines (just dried an cracked) all today , and from what I read, my motor mounts have 3 bolts so I'm assuming it's a 351m from that information.
The negatives
Fuel gauge don't work an there is a piece of tape on the fuel tank switcher to only run the front tank I believe, I'm not sure if the second tank functions or not since I can't ask her grandpa.
That's a fact!! Lol
and from what I read, my motor mounts have 3 bolts so I'm assuming it's a 351m from that information.
I don't know about the motor mount bolt hole identifier, but ...
A 351M (and 351C) has 8 valve cover bolts and the thermostat housing bolts to the block.
A 351W has 6 valve cover bolts and the thermostat housing bolts to the intake manifold.
Welcome to FTE! You have a truck very similar to Dad's. And I would agree that in original form the M is gutless. There are four reasons for that:
Cam Timing: The cams themselves don't have bad specs, but they are retarded via the timing set. So, replacing the timing set with an aftermarket unit will help. But an RV cam designed for a low-compression engine will help even more.
Compression: The original compression ratio was said to be ~8:1, but some say it was actually less. Obviously you aren't going to change that without a rebuild, but I hate to tell you - even then you won't as there aren't any high compression pistons for a 351M. But, if you do decide to rebuild it the way to get good compression is by installing a 400 crank and using Tim Meyer's pistons. Yes, the only difference in the engines is the crank and pistons.
Carb capacity: An Edelbrock Performer 400 intake and 1405 or 1406 carb will help. However, with the low compression you can't spin these engines very fast, so it doesn't take a lot of carb.
Exhaust: The exhaust manifolds have huge passages, so really aren't a hindrance, but the rest of the system is rather restrictive. Probably the best/easiest/cheapest thing to do would be to go to dual exhaust. But if you want headers be aware that they are frequently a problem getting a good fit in these trucks. I'm fighting that in Big Blue as they hit the frame.
At one point I had two 1981 F150's, both with M's. Dad's was stock and Rusty had been rebuilt with an aftermarket timing set, RV cam, and Edelbrock intake and 1406 carb. The difference was night and day. Hitting the throttle on Dad's was like stepping on a dead toad, while Rusty was fun to drive. But, with a bit of work and some go-fast parts Dad's engine showed 500 ft-lbs on the dyno, so the fun-factor may have come up some.
Thanks Gary, great info.
What I did today was delete the smog pump on top an capped the vac lines. And I'm deleting the a.c. pump also. I removed all the lines an capped any open holes just so stuff wouldn't get in the holes . I'm having a hard time removing the pump itself tho, I got the large bracket all unbolted but the pump seems pretty solid on there. Any advice on that would be great.
I work at o'reillys so I get a pretty sweet discount on parts, I'm going with the 1406 , my price is $266 , not bad. And as for headers I'm not going that route I'm keeping the stocks an just gunna do some 2 1/2 dual with 40 series flow masters.
As for the timing you mentioned, would you know a part number I could cross at work to get the timing set an cam?
Hitting the throttle on Dad's was like stepping on a dead toad
Still working on the visual. For clarity:
How had said toad met his demise? Had he succumbed to a natural death and looked like perhaps he was just sleeping? Or did he have a close encounter on a road with Goodyear's finest and was clearly not about to awake any time soon, or ever for that matter, and limiting his future career choices to being a bookmark?
KR - The former rather than the latter. In the latter guise he would be flatter than the proverbial flitter, and stepping on him would feel little different than stepping on pavement - unless he was "fresh". But, in Dad's case it was as if he had just croaked. As you stepped down you knew you were stepping on something, but nothing really happened.
Noob - I don't know what to tell you about removing the A/C compressor, but I'll try to add illustrations from the catalog to my web site in a bit that show how it mounts.
Oops, I missed the part number question. Basically any aftermarket timing set wii give you a "straight-up" position, meaning not retarded. Some will also give you an advanced and a retarded position, but you don't need that. Buy a good brand, which doesn't include Mr Gasket.
I don't know about the motor mount bolt hole identifier, but ...
351C/351M/400 have 8 valve cover bolts and the thermostat housing bolts to the block.
There is no timing cover per se, just a flat engine cover plate.
The fuel pump bolts to the left side of the engine block, its bolt pattern is at 6 & 12 o'clock. These are the only FoMoCo engines that have this fuel pump bolt pattern.
Got the bracket and ac pump off, thanks alot that diagram helped a lot, im doing the valve cover gaskets now , there was old CORK on them before uhhg what a mess. Im gunna have to brake clean an use a shop vac to get all the chunks out. I bought new accel wires with the straight ends because i didnt like how the 45 degree ones fit, i got the set for 19 bucks my price, it pays to work at a car part store lol. I want to try an get rid of some of these emission vac lines to clean it up a bit.
Last edited by Noobford; May 6, 2017 at 10:28 PM.
Reason: Bad speller
I go nuts when I see an engine like that - looks like bowl of spaghetti. With a little work (and a lot of money. LOL) you can have something that looks a lot cleaner.
I see you have your fuel pressure regulator where I'm thinking about placing the one for Big Blue. Any tips you can share on doing that? And, why are there two?
Also, what are the things to the passenger's side on the firewall - filters for the vacuum?
Edit: That's the NOS system! And, I'll bet the second regulator is for that as well. But, one regulator is for the fuel pressure - does it have a return to the tank?
I want to try an get rid of some of these emission vac lines to clean it up a bit.
Which lines are you going to get rid of? What is your priority on which lines go and which lines stay? Do you take the lines off your Audi's also?
I am giving you a hard time because we see this all the time on here. People rip all the lines off and then write back in with all these different problems they have. Or they get a truck cheap because it won't run right, and find out the previous owner took things off that they should not have.
True, you can take some of the lines off when you change the intake and carb. Right now with it being stock, I would research what any particular line does and educate myself as to how the engine may react if I take it off. If Ford could have left some of those lines off I am sure they would have, they didn't just put them on there to aggravate people working on the engine(though it does seem that way).
Edit: That's the NOS system! And, I'll bet the second regulator is for that as well. But, one regulator is for the fuel pressure - does it have a return to the tank?
Yes, Nitrous. The poor mans engine build.
I setup two separate systems, one for carb and one for NOS. I have separate electric fuel pumps feeding a pressure regulator as you noted. I do not have a "return" system. The fuel deadheads at the regulators. The feed is from the bottom.
However that dual setup is redundant and unnecessary. I have since converted back to a single pump/regulator and now split the outlet to the carb and NOS solenoid. I don't have a big NOS system (150HP) so I really don't have need to separate systems.
The second, now unused, fuel line can be a return to tank line - and perhaps will be if ever convert to aftermarket fuel injection like MSD Atomic or the FITech (which is on my dream list).
As you stepped down you knew you were stepping on something, but nothing really happened. 
