I tow a 6,000 lb. 5th wheel trailer with my ' 94 F-150 truck. The truck is equipt with a 302cu.in. engine. On flat terrain it tows fairly good even on Interstate highways however, in the mountains it's a different story. I had a towing cam installed and a K&N cold air intake installed along with dual exhausts and differential change from 3.08 to 3.7. This has helped somewhat but I would still like a little more torque and H.P. without the expense of putting in a 351 long block, or buying a new truck. Can anyone make a suggestion?

 

Well, at this point you will have to go deeper into the 302 for more power/torque. Heads for example, you'd benefit from a higher compression ratio as well as a more efficient intake/exhaust flow. There is no replacement for Displacement. However you could look into a supercharger which most definitely increase the power substantially. Also Do you have a cross-over pipe in the dual exhaust system? If there isn't the exhaust gases cannot scavenge properly at low rpm's which will hurt the low end response and power of the 302. I drive a 93 F150 302 w/auto+ 3.08 gears. By stepping up the exhaust to 3 in and having it shortened so it comes out in front of the right rear tire ( similar to the Lightning) I have increased the performance across the entire powerband. I also installed two highflow airfilters in order to compliment the freed up exhaust system. Oh, and you could also benefit from a performance chip. Hope this helps.
Jeremy

 

Thanks Jeremy. I've done almost all the things you suggest with the exception of a blower and performance chip. To show you how out of date I am, I wasn't aware that performance chips were available for gas engines, only deisel. Having a blower put in would probably give me 75+ more h.p. but the $ 3,500 bill scares me....ha,ha. I'm retired and don't make those big bucks anymore so the performance chip might give me what I need to climb the mountains.
My mechanic here in North Carolina tells me a 351 cu.in. could be put in but I'm sitting here thinking it's still a ' 94 and the rest of the vehicle still has 155,000 miles on it, irregardless. I drove this baby out of the dealership brand new in ' 93 and got attached to it but I didn't have towing a fifth wheel in mind at the time otherwise I would have gotten more h.p.
I don't have the equipment to tackle a job like putting in a performance chip, (or know how) but I'll ask my mechanic what the cost would be and take it from there. Meanwhile, thanks for your input.

BBest

 

The word chip often intimidates even a competent mechanic but I asure you that the ford module aka "chip" is rather quite accessible. The tools required are no more elaborate than a + screwdriver, 8mm wrench etc. Take a look at the performance chip forum you may be able to get a complete installation breakdown from another member that has gone through with the modification. I would be able to tell you in another week or so. I am planning to go with the superchips module. They claim +18 hp as well as approximately 30 ft/lb of torque which would most definitely be noticed when you get half way up the hills with the 5th wheel on. The hp/torque numbers they advertise are measured at the rear wheels also which makes it easier to guess what kind of gains youll actually get. With that modification alone your 302 would pull like a stock 351 based on the original power ratings of the two V8's. Is the tranny an automatic?

 

I should add that since your engine is freed up considerably you would be more susceptable to gaining even higher numbers than what superchips claims. Hope this helps again
Jeremy

 

Yes.....it's an automatic, matter of fact, I just picked the truck up this afternoon from my mechanic. I had a problem getting it into "PARK" and come to find out that the shifter cable broke. I'm good for another 155k miles now. He say's the chip will help. This guy works reasonable so I won't try it myself if I do go that route. My days of doing my own mechanics are over. I checked the Diablo site out and it looks like I could order one.
He put my truck on his dynamometer last year when he changed the differential gearing and if I remember correctly, it was pulling about 220 ft.lbs. @ 50 mph, (or around 2000 rpm), which doesn't really sound right to me. The readings were taken off the rear wheels. He attributed the lower reading to my tires which are larger than mfrs. originals. Makes sense to me but I'm about 40k miles from needing new ones.

Bob Best

 

if you are going to do all that you should put bigger injectors in. you could also have the engine and injectors cleaned using Sea Foam. people say it helps alot. I used it in my dirt bike and snowmoblie this weekend. dont know the results of the snowmobile but it sure reved up nice and very powerful and the motorcycle I can do a wheelie without trying. yes a bigger tire is going to make it have less power at the wheels if you dont have a lift i would go with 30" tires

 

Not trying to down the chip, but I can tell you for sure that putting a chip in won't make a 302 pull like a 351, it just wont happen. I ran a Diablo chip in my truck for a couple of years and it does help out but it won't turn your truck into a monster, the gains aren't earth shattering.

 

I guess there just isn't any cheap fix. It seems to me that the best thing to do would be to put in a long block 351. Here again, you're looking at a 5,000 dollar bill but you have a brand new engine. Alternately, I could go around to a junk yard and see if I could locate one that's not beat to hell. Motoshrump is right...."there's no replacement for displacement".

 

In answer to dhag911. Yes, I put a can of Sea Foam in both tanks and it helped. Short of putting in new injectors, or larger ones, this seemed to give 'Ol Betsy a little more get up and go.....or maybe I thought it did. The people at Auto Zone tell me it's their best seller so that say's something.

 

Sorry 95 F150, I absolutely agree that a stock 302 that is chipped will not have the same grunt as a stock 351, I was just trying to take into account all the modifications that RJbest has in his setup and then adding the chip while comparing that to the baseline hp/torque figures of a factory 351. I agree that the most economical route to more power would be to swap in a sound 351 block. The advantages include the ability to retain most of the performance parts that you have put on the 302. I believe the headers are compatable as well. In regards to the oversized injectors, they will help but are most effective only under high rpm conditions. One problem that they can contribute to is cylinder wash. The engine can only burn so much fuel with the amount of air that it is mixed with. Since the engine is not supercharged it would have a tendency to run extremely rich when cold and at low rpms. The 02 sensor will try to accomodate the extra fuel but it can only go so far. If the air fuel mixture is not met the additional unburnt fuel will slowly migrate its way into the crankcase mixing with the oil which can eventually lead to bearing damage. Any proper performance chip (Superchip, Diablo,etc) changes the pulse width ( How long the injectors are open for) in order to allow the extra fuel delivery. A stock system generally runs the injectors at 90% duty cycle. The chips will push them to 100% thats where the 10% power increase generally comes and when combined with better ignition timing maps etc. If you were to go with oversized injectors on the 302 a set off a 351 would provide more than adequate fuel delivery without any problems.

 

I think the 351 block is the way to go when all's said and done, there just is no "magic bullet" and when you think about the cost of a blower, I'd be crazy to put one on an engine that has 155k on it. I checked the Action Auto Wreckers website and they responded with a used 351 thats in good shape for $ 750 + $ 150 shipping costs. An extended warranty is available for 6,12 or 18 months, ($ 99 to $199) so the cost equates to around $ 1,000. Another $ 1,000 roughly to put it in. It looks like the bottom line is around $ 2,500 to $ 3,000 turn-key for the works. This is better than buying a new , or even used truck. Has anyone dealt with Auto Wreckers before? Are they on the up and up? I'd like to thank you all for your input. I got an education out of this.
BB

 

Glad to be of assistance to you, I myself do not have any experience with Action Auto Wreckers since it is a hassle to have anything shipped across the border to Canada. The 351 although initially expensive will provide you with a more reliable hauler as the mileage creeps up. The 302 is a bulletproof engine but as with everything under the sun it has its limits. Have a good one. Oh and if you get tired of the 351 theres always the 460.
Jeremy

 

Ha,ha. I wanted to put a 460 in but my mechanic tells me it wouldn't fit and the motor mounts are different among other things, ie: transmission etc.

I used to spend alot of time up your way in the Maritimes years ago. I had a 11 1/2' truck camper in those days and hauled it with a ' 72 Ford Camper Special. It had the 390 in it and I got 9 mpg whether I had it on or not. Of course gas was only 29.9 then. but everything is relative as far as expenses go. We used to go up to Cape Breton, usually for a week. I used to stop near Halifax and load up with 5 or 6 cases of Molson's Blue before the journey up the coast.
Nice talking Jeremy.

 

Motoshrump- interested in the 2 high flow air filters you speak of, I was looking online to get one for my 95 f-150 5.0 but found none.