Why would anybody say from a pure performance aspect under varying conditions, daily driving to road racing, a MEFI IV (speed density calc system) would be better than an upgraded OEM ECU using a MAF?

We have a history of using both systems on new and used LS1s, LS2s, LS6s and custom built engines in cars, sandrails and other applications and the OEM systems outperform the MEFI unless the MEFI is employed with alot of dyno time and specialized custom mapping.

So lets hear it! What's everybody else's experiences? Bear in mind I'm talking about hands on with over 100 LS engines, so spare me the one car story, please.

 

I can't imagine anyone saying that, from a performance standpoint, the MEFI system is better. I think the road that Painless and Turnkey are taking is the simplicity of the system. It costs more in the end, but I guess a well known company like Painless can sh$% in a box and tell the average consumer that it is better, and people will buy it.
From what I understand, the big selling point is how compact it is and how simple the hookup is.
Just my $.02

 

Like you say all the big boys like to push their $500.00 black boxes they can sell to the unknowing general public for $1500.00. Sounds like EXXON/Mobil scale profit margins eh?

Here's pic of motor we did yesterday for Sandsport show

 

Look'n nice Lee!!! I can see why it is a pain not to be working on miata while you keep helping install other V-8 Ls1 conversion like that. Good luck nd llok forward to your up and running. I think you like it!!! After driving my Ls1 powered miata for its first time out is something that i will not forget. Issues to resolve, but it runs hard and strong....you can ask the 4.6L mustang that got its A$$ handed to it will it did a fly by on me!!!!

 

I have seen just about it all when it comes to Maf vs Speed Denstiy, and the less tunning of the two has been the Maf for me. It seems that the maf can handle a cam better than Speed Density, if you do not want to spend a large amount of time tunning.