My question is,I have a 95 f150 302 with stock heads and stock rear end with 3.55 gears.I tow a 4500lb trailer and on level ground no problem.When I tow up hills and higher elevation ( 3000 to 8000 feet ) I struggle a bit.I changed the cam to a .480lift 260 duration,installed shorty headers and 3" cat back exhaust this help a lot but I need more.What would get me more towing power.Fords aluminum racing heads with 194 intake or switching to 3.73 or 3.90 rear end gears.

 

gears 100%. 3.73 4.10s anything lower that the 3.55s and you will feel a bigger difference before anything under the hood

 

4.10s would be a good jump with the OD. The 302 will feel much peppier on the lower end

 

Gears definitely, you'll also spend a lot less on them than more engine mods. You have done the Sixlitre tune-up, right? it's a very cheap way to gain some extra performance.

 

Will 3.90's give me that extra ommph from about 1000 to 3000rpm over 3.55's.I don't want to go to high.

 

What size tires are you running?

 

235/75/15 with a tire height of 28"

 

if it were mine, I'd be doing the heads. you stand to gain way more with the heads...and you could bump compression into the 10's and run 89/93 or 91 if its available in your area. also I'd be eagerly waiting for the 302 to seize so I could replace it with a 5.8 or a stroker winsor.


itll be near upper 2000's for rpm with 4.10s at 70. id rather have the power.

 

I would take the 2k RPMS at 70 MPH.

Gears are your best friend. ...assuming you can set them up. The OP already has a cam so I vote for a more reasonable gear for a towing rig....especially a 5L model.

The other consideration is whether the truck has factory converters. If so, ditch them for an aftermarket high-flow.

 

youd take the rpm in the upper 2000's? itd be something like 2800 give or take 100.

 

I read that as 2k....oops.


Edit: I see ~2400 RPM on my calculator...not bad IMHO.

 

which overdrive ratio did you use? 2400 isn't horrible, certainly livable, but im getting 2850 with .8 od and 4.10's

 

If it were me, I would swap to at least a 4.10 ratio (3.90 if your a cheap bastid like me and don't want to buy a new carrier) Although I'm not sure that 3.90's would make that much of a difference, or be worth the time of setting up the rear end... I also rarely drive the highway, and spend most of my time between 20-50 mph (depending on how big of hurry I am, and how bad the gravel road is that I'm traveling on), so as with everything, YMMV..

Plus, the gears would be a lot cheaper than a new set of aluminum heads..

 

I installed a 3" cat back exhaust with a magnaflow muffler.The cat is high flow.Also installed headers.The cam I installed is a Comp cam with .480 lift both intake and exhaust and and 206/216 duration.After installing all this I did notice a big improvement but I need more,that is why I was thinking of new heads to take advantage of the mods I already made.

 

you could do 1.7 rockers for pretty cheap, I think there are sets for a little over 200 bucks...wont be huge difference with stock heads but its in "misewell" territory.