does anyone know what year f250s with 351ws changed from speed density to mass air?Thanks,Kevin.

 

California or 49 state truck?

 

I'm not sure if they ever did. Light duty F250 would be more likely to have mass air than a heavy duty.

 

Not sure either, but I have a 95 with a 351 and it's speed density. I find that the only upgrade that will have a drivability issue would be an aggressive cam and or bigger injectors (maybe a dyno tune and custom chip would fix it). I'm running a powerdyne blower at around 6 psi @ 5000 rpms, Jacobs ignition, was running headers till a couple weeks ago (ball got crushed, leaked bad), K&N filter and no egr stuff. Truck runs great.

 

its a 49 state truck.every one else seems to think 96.thanks guys, Kevin.

 

They never made a factoy MAS until the 4.6/5.4 new body style trucks came out. I just checked in my ALL DATA and all the way up til 97 they were speed density systems.

 

is that on the f250s or all trucks including broncos?

 

If you need a computer or swap parts, I believe the lightening came with a mass-air 351, not sure which years, or what the differences would be.

 

what im looking for is a complete engine with mass air but im not sure which donor vehicle carries what im looking for.what about a bronco?

 

Most (maybe all) of the MAF 351's are not a desirable swap from an electronics standpoint - in '96 F150's all engines were mass air, but were also OBD-II, which is a headache. If you are just getting mass air, a 5.0 (5.8 if they exist) mass air truck, '94 or '95 would be the best bet. A 302 mass air system will run the larger engine just fine.

 

Bronco's all were speed density. I believe that lightning was mass air. Ford racing caries a conversion kit that includes computer, harness, etc...When converting, the harness as well as computer needs to be changed due to different injector firing sequences. Good Luck.

 

Very few '95 lightnings were mass air - very few and far between. The computer is changed not specifically for injector sequence, but because mass air requres a mass air computer - you can't just plug in a mass air meter and go with the stock computer.

 

well i have a 96' F150 with a 351w, and its mass air. all the trucks i have seen 95 and older were speed density with efi.

 

OK, now im good and confused. it seems like there is alot of different opinions on this!

why is the OBD-II such a headache?what is it?thanks guys.

 

Looks like your mass air conversion was a success by the pics in your albums. What type computer did you use/where did you get it? Also, did you buy the conversion kit harness or modify your existing harness?