Is it possible/feasible/worth the time to tune or run an originally equipped MAF sensor car in speed density mode. For example for what ever reason a MAF sensor couldnt fit into the intake ducting.

How would you tune purely with speed density?

 

You would disable the MAF by using the ECM switch Speed Density Mode. Then you would have to tune the car by using the Volumetric Efficiency tables.

 

Yep, as DOOM mentioned, that is how you tune it.

I tried it, and figured it's not worth it. Even after several times of VE Master, changes in weather really seemed to affect the tune.

 

Intesting, I never thought about the weather. Im guessing alot of dyno time would be involved also..

 

Unless you have your own wideband setup it would be hell

 

I played with it for a while and decided it wasn't worth it.

rich Krause

 

Yeah, VE is very dependant on the weather. Tuning VE is very difficult without a proper dyno/wideband/data logging setup, because you have to get it dead on. You'd be much better off using the MAF rather than tuning via VE.

 

93+ RX7s work off of just speed density I think and they seem to do fine. They run off of just a map sensor if that's what we're talking about. The only thing that notice is most tuners tune at around 12.5-13.0 a/f. Maybe it's because it's a rotary, maybe to compensate for cooler/warmer climate.

 

I'm not saying that you can't tune in VE (speed density, MAP sensor, whatever you want to call it), I'm saying that it is more difficult. MAF is very simple, because the MAF sensor does most of the work, you don't need to worry about what the volumetric efficiency is with a MAF car. But on speed density, it is the only thing you have to tune by. For a lot of people, speed density is the only way to go, especially those who didn't originally have a MAF system and those that have maxed out the MAF. But if I had the option, sticking with MAF is a better way to go.