So who wants their ECU's "Chromed"?

[Alex3000gt]

Can we get a "How To" or "FAQ" going in the 3/S Wiki?

There is a lot of info in this thread but it is difficult to sort through with all of the conjecture and opinions.

[CoopKill]

Can we get a "How To" or "FAQ" going in the 3/S Wiki?

There is a lot of info in this thread but it is difficult to sort through with all of the conjecture and opinions.

This would be very awesome, and useful!

[Intropy]

Ask Jesse how his last engine pounded out it's bearings. My memory is foggy right now. Something about timing advancing itself 3-4 degrees under load beyond the set correction that works under no load revving that everyone does for the conversion. I could vary well be misremembering.

There is an 80 usec or so difference in latency between the first gen and second gen cam/crank sensors. A second-gen ECU expects greater lag times, which require more advance as engine speed increases.

[aaronatstate]

Ask Jesse how his last engine pounded out it's bearings. My memory is foggy right now. Something about timing advancing itself 3-4 degrees under load beyond the set correction that works under no load revving that everyone does for the conversion. I could vary well be misremembering.

Yes, and this is exactly what I'm talking about correcting for... I was not talking about timing readings free revving, I was talking about timing values from my evoscan logs under wot acceleration. Those numbers match what the ecu is calling for from the timing map. But because of the 1g sensor, it adds timing after the fact cause of the latency differenceces.

[Chris@Rvengeperformance]

Attachment 4029Attachment 4028
All you have to do is take the wire from each of the existing oem relays that would go to their coresponding thermo sensor and wire them into the ECU. The ECu is actually a ground for the relay.
The pins on the 98/99 plugs are 17 fan HI, 18 fan low.
So basically on the 1st gen pin 3(blue with black stripe) in A-55 instead goes to pin 18 on the 99 ECU plug and 1st gen pin6 (green with black stripe) in A-55 instead goes to pin 17 on the 99 ECu plug. Make sure pin 1(black) and 4(Blue with yellow stripe) are still plugged in on A-55, only pin 3 and 6 should be re-routed.
If you do it this way you don't even have to remove the thermo sensors. They are electrically removed from the circuit and won't affect anything. Plus if you want to go back to stock it will be an easy retrofit.

thanks again for this, this is a lot easier than I thought. Thanks to your color coding advice, once you pull the fan connector off it is obvious which wires to splice into. It is very nice because due to my balance tube piping I couldn't get the low temp sensor wire back on anyway.

The hardest part is just getting the wire back to the ecu. I'm debating on how hard to make this part on myself

[futurevr4man]

thanks again for this, this is a lot easier than I thought. Thanks to your color coding advice, once you pull the fan connector off it is obvious which wires to splice into. It is very nice because due to my balance tube piping I couldn't get the low temp sensor wire back on anyway.

The hardest part is just getting the wire back to the ecu. I'm debating on how hard to make this part on myself

well said

[99 vr4]

How long does that wire need to be? I was going to offer two 18 gauge TXL wires in expanded sleeving. I have everything here, I just need to know the length...

[donniekak]

Yes, and this is exactly what I'm talking about correcting for... I was not talking about timing readings free revving, I was talking about timing values from my evoscan logs under wot acceleration. Those numbers match what the ecu is calling for from the timing map. But because of the 1g sensor, it adds timing after the fact cause of the latency differenceces.

This shouldn't be a factor if the car is tuned properly. If the car likes 18* of timing in a certain load cell, the map wil just indicate a lower timing number than actual. The only issue would be people with 91-92 cars using maps setup for 93+ cars.

[Chris@Rvengeperformance]

How long does that wire need to be? I was going to offer two 18 gauge TXL wires in expanded sleeving. I have everything here, I just need to know the length...

there are probably 10 different ways to run it. I think 12 feet would cover any reasonable wire routing.

[aaronatstate]

This shouldn't be a factor if the car is tuned properly. If the car likes 18* of timing in a certain load cell, the map wil just indicate a lower timing number than actual. The only issue would be people with 91-92 cars using maps setup for 93+ cars.

Yes, thank you I understand how it works. I don't understand why I have to explain that I do know what the hell I'm talking about so many times.

I have a 91-92 car, that's the point. I have a 1g cam/crank setup, and I am using a 99 ECU, so I have to compensate for the latency differences in the maps, so I do not run to much timing. i.e. I want to run 20 degrees of timing at 7000rpm, I need to call for 16 degrees, that way after the latency differences, I actually do get 20. See I do know how it works, thanks.