I too am very interested with turbocharging my inline six, I have a 1996 F-150, with theM5od five speed and a OBD-II 4.9L. I was wondering how much of a pain it would be with the OBD-II. Because of the Mass Air Flow sensor, the engine SHOULD see the turbo throwing more air, pick up on it, and add more fuel accordingly, Right ? I dont know for sure. If anyone knows more about the beauty of OBD-II than i (which im sure isnt too hard) I would be interested in hearing what i can and cannot do, Thanks for all replies guys.

 

To tell the truth, I don't know if the MAF sensor should be before or after the turbo. If it is before, you would have to route any pop-off valves back behind it, and if it was after, I'd worry about melting it. I am building a 300-6TT now, but with the older style EFI, and a custom computer. I am not sure about what manufacturer I am going to go with yet, but since this will be a race-only engine, I might make up an interface, and a program to run it with a laptop.

Jared

 

whenever you add boost to an efi engine, its always a good idea to chip the computer, that way it wont get confused with all the air coming in, and will put in enough fuel so that you dont run lean. IIRC, maf sensors go before the turbo/supercharger, and would not pick up on the flow anyway.

 

On my friends 95 5.0 OBD-II with MAF his turbo is before the MAF sensor so it does pick up on it.

He got a Granatelli MAF meter specially made and a super chip burned for it.

 

Hey guys, thanks for the replies. I guess i forgot to mention, the turbo i want to use is one i already have. I got it from a friend of mine, he said he got it from a guy who had it on a 5.0 mustang. The turbo is a Rotomaster AR/60. If i would use this will i have to change all of my injectors and all that too or not. If anyone knows much about this turbo, your input would be greatly appreciated. Thanks again guys

 

ok, here are some basic things you should do or have done to your motor in prep for a turbo

1)injector swap to at least 19lbs, maybe even 24 if youre going to run a lot of boost.

2)port the head and give it some bigger valves to optimize it for the extra air pouring in.

3)make sure the motor is in good tune, that way you can always revert back n/a power.

4)if youre going to run more than about 12lbs of boost, lower compression pistons would be a good idea, you dont want anything blowing up on you.

theres a lot more detailed info on this subject around, as im sure youve seen. just have fun with it and see where it takes you.

 

With a MASS air system it is possible to run a turbo without programming. You will need an FMU to up the fuel pressure with boost. Where the MAF goes is a matter of debate. It is subjected to more heat when downstream of the turbo, but when it is there it reads the mass of air that is actually going into the engine. If you put it upstream of the turbo and use a blow off valve there will be times that the engine runs very rich because there is air blowing off that the MAF has already accounted for. If I was going to do it I would put the turbo on the passenger side of the engine compartment and run it to a Powerstroke intercooler so that it crosses over to the other side of the truck. Then through the MAF and into the engine. Boost enrichment can be easily handled by an FMU so the computer won't know the difference. The only thing it will know is that you're at WOT and there's a lot more air coming through the MAF. I would install 24 lb injectors and a larger MAF that is calibrated to work with them.

 

Don't forget a higher pressure adjustable regulator. Without more pressure, you are going to burn holes in the pistons.

Jared

 

The FMU takes care of enrichment under boost. It does nothing until manifold pressure goes above barometric pressure, then it increases fuel pressure in proportion to boost.