No MAF

[ssweet99ss]

My brother just recently had his car tuned and the tuner unhooked the MAF. I always thought that the MAF was only deleted when it wasnt NA, what does unhooking the MAF benefit?

[mistermike]

Less restriction without MAF. Better throttle response. More accurate fueling, provided the tuner maps out your VE table thoroughly, and performs charge bias temperature compensation. If he uses EFI live, he can get it even closer.

[ls1camino]

Called a Speed Density tune...I think it used the data provided by the MAP Sensor to properly mix Air/Fuel Ratios.

[ssweet99ss]

Called a Speed Density tune...I think it used the data provided by the MAP Sensor to properly mix Air/Fuel Ratios.

Is it better?, some say it has better throtle response.

[Firebug]

Is it better?, some say it has better throtle response.

Less restriction without MAF. Better throttle response. More accurate fueling, provided the tuner maps out your VE table thoroughly, and performs charge bias temperature compensation. If he uses EFI live, he can get it even closer.

I definitely think so... Particularly in the lower rev range.

[ssweet99ss]

How much trouble is to switch over to a speed desity tune?

[mistermike]

How much trouble is to switch over to a speed desity tune?

Unless you tune it yourself, leave it alone.

[ls1camino]

Unless you tune it yourself, leave it alone.

Huh?

I think what he means is this...get a good tuner cause the car won't run right (or possibly not at all) without a tune.

[ssweet99ss]

Huh?

I think what he means is this...get a good tuner cause the car won't run right (or possibly not at all) without a tune.

In your opinion would you switch over from a MAF tune?

[mistermike]

As SD tune has some advantages over a MAF tune if done right. It's not that difficult, but is is very time consuming. More time consuming than you probably want to pay someone to do for you. This is why it tends to remain in the realm of people who do their own tuning. To do it on a dyno, you need a Mustang or Dyno Dynamics, and still have to do a lot of road logging. It takes the better part of two days. If a "tuner" charges you $400 for a 2 hour dynojet tune, MAF hack, timing tweak, do the math. Timing, for the most part, should still be left to a pro on a load dyno, but fueling can be 100% accomplished on the road.

[mark21742]

As SD tune has some advantages over a MAF tune if done right. It's not that difficult, but is is very time consuming. More time consuming than you probably want to pay someone to do for you. This is why it tends to remain in the realm of people who do their own tuning. To do it on a dyno, you need a Mustang or Dyno Dynamics, and still have to do a lot of road logging. It takes the better part of two days. If a "tuner" charges you $400 for a 2 hour dynojet tune, MAF hack, timing tweak, do the math. Timing, for the most part, should still be left to a pro on a load dyno, but fueling can be 100% accomplished on the road.

I did my SD tune myself (with lots of help from lots of people on here) and it took me the better part of a month......so I know I wouldn't want to have paid for all of the tuning time, but I love it.

temps during my street tuning varied from 12°-65° so I had lots of different (real world) variables that made it harder to tune, but overall gave me a dead on VE, optimed spark and 0 knock retard to get the most out of my h/c swap......i still need to dial in the MAF and run it to pass emissions......the MAF will only be back on my car one day every other year just to pass emissions
( you have to pop a MAF fail code to get the car in SD mode)

[Dezert]

Ok So reading these responses brings me to a whole new question. What part of the equation does the actual outside air temps make when programming your car? Since I had mine programed in the late winter is that going to affect how it runs in the dead of Summer? I am running and SD tune on my LS1

[mark21742]

Ok So reading these responses brings me to a whole new question. What part of the equation does the actual outside air temps make when programming your car? Since I had mine programed in the late winter is that going to affect how it runs in the dead of Summer? I am running and SD tune on my LS1

colder air = denser air
the computer looks at the air temp in your tune, compares it to the current air temp and adjusts for the difference