Speed Density to MAF upgrade ??

[Mustang_289]

Starting to do research on next round of upgrades for our project stang. I've heard that speed density doesn't work well when you start making performance mods to the engine.

Can anybody comment on this - and how tough is it to convert from SD to MAF? Is there an actual kit to do this?

[greydan]

I've been looking into this myself. Seems if you do a regular rebuild, with a light bore, and trick bolt -on stuff like pullies , cold air intake, and a hotter ignition...speed density is alright. As soon as you talk street cam, increased intake bore - header sizing..and a set of upgraded heads...your into mass-air to handle it all properly.
There are people out there, who really know their stuff, who could maybe tune around speed-density...but mass air is the best way to go...just plan on it.
Interactive has got a bolt-on upgrade for $380. From there it's all +++ towards about $700 with-out getting trick stuff. Or, get a set-up off of a 88 to 93 with the 'puter, meter and harness used...about $200 up.
For a 'hot' engine, with bigger injectors, you really need mass-air and matched metering for the injector sizing...plus probably chip work for the 'puter.
At least thats what I'm getting from what people tell me, and I read.

[fordgasm]

My 87 started out as a speed density car which I converted to mass air after making a few mods. You can make several mods before the need for mass air but most have to convert after heads, intake and cam mods. I eventually had a custom burned chip to cure a couple of driveability problems.

The mass air conversion is really pretty simple to install. They come with good instructions that will walk you through step by step. I would recommend at least planning on the conversion if heads, intake and cam mods are in your future.

[Unit 5302]

With the addition of an adjustable fuel pressure regulator you can bolt decent cams, aluminum heads, and good intakes onto your speed density car. Adjusting the fuel pressure allows you to keep the management within the computer's limits.

In other words, a couple of the guys running low 12's would seriously debate that speed density cannot be modified.

[greydan]

What is the indicator that you look for, when you adjust the fuel pressure with an adjustable regulator?
Accessive richness e.i smoking or leaning (pre-detonation) ..or do you meter something first..as in vacumn ?????? Is there a balance between fuel pressure and timing....?? or do you just time, then adjust fuel pressure for best possible run performance.?

Back to the up-grades with speed density. I intend to rebuild; bore only for a clean-up, o.e.m. piston set, street cam, a better than o.e.m. Gt header, and would rather install a cast up-grade head, than a pricey alum. set. (budget build)
It's a roller 87 stock 302 now.
If I use the speed-density, I'll be adjusting fuel pressure for ................. ??
The thing will probably go to the strip once, then be a street car untill they pry it from my dead hands....<g>
My concern has been that I've met someone who did the above, and had a rough runner with fumes poring out of the pipes, because it was running so badly. He said, the lack of a mass-air up-grade was the problem. Sounds like the lack of a good speed mechanic was more correct.

[Stang Runner]

Look at My sig I have yet to get it tuned up good But should get a Mid 12 Ez on it.

[Stang Runner]

(and had a rough runner with fumes poring out of the pipes, because it was running so badly.)
LOL yep That is my car as it is right now But I think I will be able to get it Up and Running good still.
But Crap As long as the Gas is smashed down it HALLS not tell 75MPH did the car Hook up well it did tell I blew 3nd in the tranny I need to get that fixed a New Fuel Reg on it too.