Hello all i have a question,
I have a 91 f150 with a 302. i want to give it a little more power.
I just put dual exaust on it and i want to put in a little cam. I was told that i cant because i dont have the mass air sensor and if i did it could mess with the computer, is this true.

what other (cheap things could i do for more power)

thanks

 

There are aftermarket cams that will work, but what you have to choose from is very limited. What you want to look at is lobe centerline...it can't be any lower than ~115* I think. I can tell you form 1st hand experience that a centerline of 112* will throw the speed density computer way off. There may be other specs that will limit the cams ability to work with Ford speed density but centerline is the big one.

 

Nope!! The Comp Cams 31-255-5 works fine with SD.

The cam is the cheapest thing you can do that will produce any significant power boost. Longtube headers are the next thing.

 

are these cam numbers the duration and lift and are we positive this works with no problems
thanks

 

Sounds like a comp cams part #...

 

It's a part number. Not sure on the specs, but it definitely works fine with the speed density computer.

Frederic put up an excellent post a few months ago on why certain cams don't work. I'll see if I can find it, it was a great post.

edit: https://www.ford-trucks.com/forums/5...e-rebuild.html

Long read, but worth it.

 

thanks all for the inf much appreciated

 

Another question guys, with that comp cam do i need to change the pushrods or springs? or am i good to go? Did some asking around today seems i need to order the cam and lifters through the states. also this cam is good for a little more low end tourque right?

 

Should be...if you go to www.summitracing.com you can type in the comp cams part number or even the comp cams site and it'll bring it up...telling you the year range...the specs and the recommended parts you should do with it...you will of course need new lifters and possibly pushrods..but I doubt it on the pushrods...it shouldn't be too high of a cam to not work with the stockers...cuz then theoretically it wouldn't work with your computer.Exhaust,long tube headers, and possibly UDP's...don't wanna forget rear gears.

 

mmmmmmmm i wonder what kind of gears are in there? and udp's pullies right

 

Probably 3.55:1

Changing the differential gears wont give you any power though. All it will do is allow the motor to rev quicker when in the trans is in gear....or rev slower depending on what gears you use.

Underdrive pullies? Might be a good idea if you spend alot of time at particularly high rpms (thats what they were invented for) but if not then I don't see how they would be all that helpfull. I guess it would all depend on how overbuilt the cooling/charging system is on the rig.

 

all im really after is some tourque lay rubber, get up to speed now power lol.
so all the info is good guys thnx

 

The underdrive pulls help your engine to rev up quicker which in turns gives you a little more horsepower and makes the truck seem like it's got more torque...Changing the gears will help you out greatly if you're looking to get up to speed qicker...and it'll lay a little rubber......doesn't necessarily have 3.55's...my 95 came with 3.31's......a little bit sluggish for me...so I swapped out the axle for one I had in a parts truck...3.55's and a posi.....I'll probly change those out to 4.10's in the future...them 3.55's aren't good enough to run with a gen 1 lighting....even a stocker.....get a better air filter if you haven't already...at least a drop in filter...not a stock one...the cold air intakes are pretty useless on our trucks...doin nothing but sucking in hot air.

 

well i orderd my cam and lifters today they had to come out of alberta. so i guess i need intake gaskets, aswell as head and waterpump gaskets, and timing cover gaskets. well i'm at it a chain and gears. i havent worked on a fuel injected vehicle much, last time i worked on a 302 was in my 84 stang. Anything i need to know or watch out for?