ive got a 81 f150 that originally had the inline 6 and i decided to swap it for a 302. was wondering if the ignition would have to be replaced to support a bigger motor?

 

The ignition would have been the same between the six and eight engines. There is a minor difference in the harness that was needed if you have a factory tach, but otherwise they were the same.

 

You know about the frame brackets you will need for this swap correct?

 

And the different radiator? And the fact that you'll have far less torque?

 

You could also lower your TRUCK to just about 3" off of the ground. That would round out the whole swap idea....

I6 = Truck motor
302 = Mustang motor

 

Good idea! Why didn't I think of that!?!? It would help MPG as there would be less drag (wind, although parts might drag instead at times). And, look cool! Add some Customline Ventiports and it would be right in style.

 

i hate how everyone says the 300 has more torque than the 302, its got the same torque numbers. just a different rpm, if the truck is getting used for towing yes id like a 300, but daily driving and more as an occasional driver give me the 302! can be made fairly quick on the highway with the right gearing. my 300 coudnt get out of its own way, but had good lugging power

 

Here's some food for thought: A 4bbl and a set of headers puts you right at 200 horsepower/300 torque with the 300-6. Right on par with a factory 351 High Output, but with better gas mileage.

A 300 also DOES produce the same torque and horsepower as a 302, provided both are stock. However, the 300 is doing this at a lower RPM with an asthmatic 1bbl carburetor and a set of turd manifolds, while the 302 has those nice cross-flow heads and a 2bbl from the factory in 81. I think it speaks hugely that a six cylinder with a 1bbl carburetor gives the same peak power figures as a V8 with a 2bbl carburetor.

So the question is, are you willing to take a truck that was geared for a low-RPM motor and stick in a motor that was designed for higher-rpm operation? To get the 302 to produce any kind of useable power in your truck (and no, this doesn't factor in towing, this is just for off road and daily driver usage) you'll seriously want to consider 3.25 to 3.50 gears (an 81 should have a 9'' rear) so that the motor won't constantly struggle to push your truck.

If you want your 300 powered truck to have more giddy-up and go, put in a lower set of differential gears. 3.25/3.27 is a good set if you don't have overdrive. The factory liked to use 2.47-3.08 gearing in 300 equipped trucks.

Want more than that? Get a 4bbl and headers. Want more than that on a cheap budget? Put in a 351. Skip the 302.

For reference, here's a video I found yesterday of a guy who has a 240-6 (a 3.9L, smaller brother to the 300 that has a shorter stroke and longer rods) in a 67 F100. He's got a 4bbl and headers on this 240. If he had the bigger 300, it would've been even quicker.


Power is subjective to taste, do what you will/want. A 302 or a 351 is just like a small block Chevy. You see them in everything.

 

Good points made by all. In summary, you can put a 302 where a 300 was by changing the mounts and radiator. However, given the 302's torque being made at higher RPM and Ford's typical gearing behind the 300, to get it to perform you will need to change the gearing and that will reduce the MPG. IMHO it can be done, but shouldn't be.

 

My father drove my truck the other day and told me it reminded him of all the old farm trucks he drove growing up. In the next breath he said, "If you put a V8 in this truck, it'd ruin it." And he was right.

The next thing that was said, "Why would I want a V8?"

 

I dont know if yall know how broad this dibate really is. Its big in the diesel community also. Thats one reason the Cummins is so popular compared to the legendary 7.3 PSD and DMax. I love the power split on the inline motors vs the V-motors, far more low end torque with the same hp.

 

ok the swap already has taken place and duh with the brackets and radiator. and another thing im not looking for a farm truck this is gona be my daily driver for work. thanks for all the stupid replys in there.

 

Welcome to FTE. There are some exceedingly knowledgeable and helpful industry experts here who will oftentimes go out of their own way to help others.

But...

Writing in all lower-case with poor English & grammar is reminiscent of a child, doesn't earn you any respect, and can set the tone for the thread.
You were warned in red lettering in the forum's Sticky which you should have read before posting here.

Nevertheless, you got some help from some of this forum's best guys, despite their playin' around (notice the ).

Perhaps if you had explained yourself better and wrote in a non-childlike manner respectful of the English language, that wouldn't have happened.