Postby Metallicork » April 2nd, 2009, 7:32 am
smokey1275, read this....
For those who want to know this is how you fix the rev cut on 20v conversions running standard ecu that dont have the speed sensor hooked up. These cars will have a lower rev cut than cars with the speed sensor operating.
I found many ways to fix this problem but all of them ranged from $100 - $600, these incuded speed tranducers, trick boxes, instrument clusters, etc. Instead all you need are magnets some wire and a magnetic reed switch. You can get all this from a electronic store for under $20. Some basic soldering skills will help as well to make it neat.
My car is a AE92 CSX.
All I did was cable tie two magnets to the driveshaft (the long shaft in the middle that doesnt move with the suspension) and then attach a magnetic reed switch next to it with one wire going to earth and the other going to the purple and white wire on the 12 pin plug connecting to the ecu. You need to use a multimeter to test the switch is in the right position so it opens and closes as the driveshaft spins. I was bodgy and just used a little bracket and some wire to put the switch in the right spot.
The reed switch activates when the magnets pass it and sends the signal or pulse to the ecu. The ecu gets two pulses for every wheel rotation and this is how it determines your speed. In fact i bet you could probably use one magnet. For your info factory speed sensors send 4 pulses per rotation
Now because the ecu thinks its getting a speed signal it will allow the car to rev past its previous rev cut to one that is a bit higher.
You shouldnt be revving the engine this much but if you couldnt before, and your like me and wanted to, know you can. Also i dont think this will effect the speed cut either as the ecu will think the car is going 1/2 the speed in theory. Im not going to test this out anyway, someone else can if they want to.
The idea with magnets and a reedswitch came from Phil Bradshaws webpage. Hope this helps people who have this problem. Me and my AE92 have even more fun now.
at the comments you make, and the similarities to ones you made in the past.
LOL!!! 
