RCU Forums - View Single Post - Welcome to Club SAITO !
View Single Post
Old 07-10-2014, 02:50 AM
  #26974  
SrTelemaster150
Senior Member
 
SrTelemaster150's Avatar
 
Join Date: Feb 2012
Location: Brasher Falls, NY
Posts: 3,904
Likes: 0
Received 2 Likes on 2 Posts
Default

Originally Posted by blw
The Honda S-2000 suffers badly from getting heat soaked if you don't keep the rpms up on launch. It gets a big dose of hot air right in to the intake. Cold air intake boxes are a good thing for the car.
On the Gen-III Chrysler Hemis, a high IAT will cause the computer to pull ignition timing killing the 60' times. Once the car is moving, cold air entering the intake will allow the timing to advance. One trick I learned was to unplug the AIT sensor. The computer then reads the ambient air temperature & the battery (mounted in the trunk) voltage to adjust the timing. Even on cool days, I cut about .1 off my ET.

On the LX platform, a lot of the performance gains were tied to fooling the computer, as well as modifying the parameters. We called the ECU "HAL" as it had a mind if its own often negating gains from modifying the parameters. I was the 1st person to change the axle ratio in an LX. I tried to get a performance tuner manufacturer to work W/me on it, but they thought they knew it all & that merely modifying the tire size data would work. WRONG! The Mecedes based TCM reads the wheel RPM through the ABS sensor as well as the tail shaft output RPM. If the data doesn't jibe W/the axle ratio programmed into the TCM, the car goes into "limp mode" staying in 3rd gear W/only partial throttle available.

I went ahead & swapped in a 3.06 AMG diff from an SRT8 (stock 5.7 ratio was 2.82) & sure enough, shortly after the trans shifted to 3rd gear, the TCM went into limp mode. I found that limp mode wouldn't initiate until the trans had run in 3rd gear for several seconds. I drove the car for several days by accelerating fast enough for the transmission to shift into 5th gear before it went into limp mode so that even W/only part throttle, I could cruise along @ 65 MPH. When I had to stop for a stop sign, (infrequent in my rural area) shutting the ignition off & opening the driver's door would re-set the TCM. I started a THREAD on LXforums & soon found someone to hack a TCM for the ratio change.