Hi everyone, I'm looking to switch to speed density on my 05 gsr and looked at all the tephra roms, it seems that all of them are using the fuel temp sensor for air density compensations based on temperature, I know that people are also using the gm iat wired into the maf which is what I want to do. Can I modify one of the tephra roms for this or is there another rom that I need to be looking for? Thanks in advance and Merry Christmas!

 

You can use the Tephra V7 ROMs (96531706, 96533706 or 94171715). Just de-pin the Fuel Temp sensor and wire your GM IAT on a new pin in the same position.

 

Thanks for the reply! So how do people use the spoolin up harness that plugs into the maf then? I guess if I will have to I will wire the sensor into the fuel temp but would prefer to use the spoolin up harness.

 

As cdrinkh20 said.

 

One end of the Spoolin' Up harness plugs in to the GM IAT, and the other connects to the MAF plug on the OEM harness. This feeds the GM sensor temperature signal back through the MAF harness and into the IAT input on the ECU. This saves you from having to do any work if you hate splicing wires

You then simply select the IAT temp input using the "SD Option: IAT Input for MAT - Use 0x03" in your SD 2.0 ROM settings.

 

Thats all I was looking for! Thanks a million dude! Can i still use the gm iat with the speed density 2.0 rom? I like that rom better due to it have a 3d ve table and will most likely be tuning the car on that version of speed density.

 

Yes the GM IAT works with all the SD 2.0 ROMs. Think about (and research), the best mounting location for the IAT depending on how you plan to use your Evo. It can be mounted in the intake manifold by drilling and tapping the boss which is molded into the top, but this location suffers from heat soak, and potential warm starting problems for a daily driver. A better place, because it is not affected as much by heat soak, may be in an aluminum boss on the exit end tank of the intercooler, or even in your upper intercooler pipe.

 

Cool! yeah I have a bung on the lower end of the upper intercooler pipe, i'm aware of the heatsoak issues just couldnt find much on the specifics on how to setup the rom for gm iat, maybe i'm bad at searching but thanks for your help again!

 

Im new to tuning can you please give me break down on what. Use 0x03 means?

Is that like a mut location?

 

No, it is a hexadecimal variable that you set in the ROM before you load it into your ECU. (Any number that follows prefix "0x" is hex, or base 16, by convention). It tells the ROM software which input pin to read for the IAT signal. 0x03 tells the software read the value from the MAF temp input. 0x0E tells it to read from the fuel temp input.

 

Right but were exactly does this number live, and were does it get inputted or changed?

 

here!

 

cdrinkh20 - Kind of off topic . At what RPM you are getting full boost on your setup ?

I am thinking to switch to kelford 272s from tomei pon cam type R 272s .

96534706 + non ported head , tomei valve springs - retainers.

 

4250 RPM in 2nd
4000 RPM in 3rd
3750 RPM in 4th
3250 RPM in 5th

 

Thats going to be nasty street car.