I have an 85 that I have had continuous computer and wiring problems with. I finally got fed up and purchased an 86 harness and computer. I am in the process of installing a new engine combo and am now debating whether to stick with the mass air flow system or convert to speed density. I know, I know.... its like beating a dead horse and yes I have searched but my questions are more specific to my application.

My combo: 383 with a mini ram, Alum. Edelbrock victor jr 215cc heads, 11.2:1, still debating cam specs will be either hyd flat tappet 240/246@.050, Lift .550/.561/ or hyd roller 239/239@.050, Lift .558/.558, msd digital 6plus ignition and coil, aeromotive a1000 fuel pump, fuel pressure regulator and fuel pump controller,150 horse wet nitrous with progressive controller, 6 speed tranny and depending on where the motor makes power a 3.07 3.55 and 3.75 rear end gears with a 26x11.5 et street.

I talked to the guys at tpis and they are telling me to go with speed density. I also talked to Alvin at pcmforless he told me it would be good either way. I have some friends who race mustangs and everyone of them that has a speed density system switches to maf when they get serious about power. I would like to buy the stuff I need to tune myself and with Alvin's help think that I can dial it in with no problem. I guess my question would be which system would best suit my combo and horsepower needs (I would like to make 500 to 550 na and 650 to 700 juiced)?

Also is there a company like pro-m that makes a larger maf or a conversion to use a larger stock maf?

 

I's a nice idea but it won't help, even if there were one avialable. The problem with TPI MAF isn't flow, its resolution. The ECM's code simply can't read more than 255 grms/sec. There was talk some time ago about usng a larger MAF (16 bit) with a converter that would basically halve the signal back to 8 bit...then there were issues of there being no smooth, fine graduation in the readings which would cause driveability and idle problems.

IMHO Alvin is right, either system will do what you want. The advantage of MAF is that it is pretty forgiving with regards to engine mods where as the MAP systems are completely intolerant of change and have a steep learning curve for tuning and require lots of fine adjustment. The plus to MAP is no 255 code limit and if you decide to go with forced induction you can easily swap to the 749 ECM and a 2 or 3 bar MAP sensor.

 

Alvin said something about a conversion that was an estimate on HP per grms/sec does anyone know what that formula is