Speed delimiting

[endless551]

Hi guys, was driving on penchala link couple of nights ago and pushed my car up to 180km/h till the speed cut kicks in.. Felt fairly harsh like I hit something. Went back and looked at the ECU pinout diagram but can't seem to find a speed signal. So I reckon the speed cut is triggered from the speedometer and directly to the ecu for fuel cut signal. Removed my dash over the weekend and found one of the screw point with marking '180K 20000M' also a '100K, 120K' point with no screw on. So I guess that would be the warning buzzer for overseas markets but ot used for JDM. I went ahead with removing the 180K screw as I can see from the printed circuit board that it is just one signal going back to the ECU as though its for triggering something. Haven't got the chance to bring the car above 180km/h yet.. might do it tonight on Penchala Link again :D. But am I doing the right thing? Is this how the speed cut on FC3S functions? Other than buying those useless and expensive RSM or similar sort of modules. What r the cheaper ways of doing it???

 

[777hp]

yes .. 180k screw , just removed it .

rsm dont work with fc , it shown rpm .. but not speed .

 

[endless551]

Removed it... it worked.. but my speed sensing power steering didn't work.. Lots of 'whiplashing'/tramlining on my steering wheel on high speed corners in 4th when there r little humps in sepang.. decided to put it back on since my stock car can barely pull 180km/h down the straights.

 

[777hp]

i think is just because uneven surface on the track or traction of your tires are not good ,

if then better get a program ecu , dont need to worry about modifiying ,

 

[Mazdaspeed A-spec.]

rsm can work for fc, just need reed switch to take speed signal from standard speedometer. The easiest way is get a knightsport or any other upgraded speedometer which has speed signal to tap for rsm and no need to worry about the power steering issue when u remove the 180 screw.

 

[777hp]

mazdaspeeb ,

you finally install a rsm in your car ,
thanks for the update ,