Hello guys,

I am sorry if I am annoying anyone by asking this question but in all honesty it is something I have wondered about and what a better place to ask? My truck is a 1994 supercab 4x4 with a 302 and a automatic transmission. My truck came factory with the mass air flow computer. Unfortunatelly the 302 is dead. I paid and had a new water pump and a harmonic balancer put on the truck after both of these items were in need of replacement. On my way home from the maiden voyage something happend steam and smoke come from under the hood and out the exhaust. It literally looked like a big rolling joint with as much smoke and steam was coming out. now the engine sounds like its knocking and with 295,000 miles I think its time for a replacement. Anyways with that being said I was wondering If the 300I6 would be a suitable replacement. Would the Mass air flow computer run the 300 and would the 4r70w transmission combined with the 3.55ls gears be a suitable combination? I know alot of people are going to give me crap over this but it is just a thought. I loved the 300I6 I had before and thought it might be a suitable replacement?

Thanks guys,
John

 

Welcome John!
As for anybody giving anybody crap, certainly not here I do believe that the MAF system does work with the 300, I wonder though if you'd have to reflash the computer or get one specifically for the 300 system for proper air/fuel ratios etc.
There's many good things to be said about the 300. Definitely I BELIEVE that it would give you better torque than that 302 in that truck. The 302 may be better at top speed, but I know many guys that would rather have the 300 because it doesn't "lug" at lower rpms due to its torque band.
With the transmission, I wouldn't see why it wouldn't work? The bellhouse patterns should all be the same.
Now don't think badly cuz I don't know automatic tranny terminology, would the 4r70w tranny be a 4 speed overdrive? I ask because this most certainly affect the desired rear end gear ratio. If it is an overdrive, I'd say 3.55 would be more than fine. If it wasn't, than I would consider dropping down to a 3.25 or the like. I hope I've helped you in some sort of way, there's many knowledgeable guys on this forum so I'm sure they'll chime in and correct anything If i've made a mistake

 

it can be done. its fairly straightforward as ford made the engines fairly interchangeable and the i6 was the longest motor you could put in a f150, (as long as a v12) however you will need to get a pcm for a truck with a 300 and an automatic. i am pretty sure that by 4r70w you mean e40d check your drivers side door pillar, under the trans section it should have a e for e40d and it will be an e40d unless something was swapped. to get a 300 with mass airflow it will have to be from a 95 or 96 ONLY as these are the only two years they came with mass airflow and a obd II computer, it is best if you have a whole parts truck or take parts from the same truck, if you do go to the junkyard pull the pcm from the truck you are taking the motor from as long as its a 95 or 96 and it has a automatic trans. a pcm from a manual trans vehicle will NOT work

 

The 88 donor I used is a speed density, map set up. But going through the 88 factory ford wiring diagrams. The only difference between the 302 and 300 in the trucks wiring harness was the injector harness. The rest appeared exactly the same. I bet they did the same for the next generation.

Are the 95's also MAF/obdII? I thought it was 96 only?

The OP's 94 should be an eec-v system not obd-ii.

Honestly any of the versions I would think would be a minor job to convert to the the 300.

I personally love the 3.55 gears and the 300. Now my trucks not a stump puller, with a light duty manual trans and steep 1 and rev. But around town the rpm's are kept really low and the 300 doesn't mind that a bit.

 

the early 95s may not be maf, some people have said that their early 95 didnt have maf but every 96 had it

 

From what I've heard, the E4OD and 4r70w are the same thing. They just started calling it by a different designation later in it's life to match Ford's new way of naming transmissions.
Even if it is different, though, if it bolts to a 302, it'll bolt to a 300.