Ignition Timing Qs

[PhilGTR]

Hey guys I got a couple of questions about ignition timing

I have been told that standard ignition timing on a GTR is 20 degrees.

Can someone explain to me:

1) What a timing light is or what that looks like??

2) When you plug a consult into the stock ECU to check ignition timing does that mean what is set at the CAS is what it will show on the consult screen plugged into the ECU? Or is the only real way to see what ignition timing is sat at the crank by using a timing light? Because looking at the consult it shows 20 degrees BTDC.

Thanks

[djr81]

1) What a timing light is or what that looks like??

A light that when hooked up flashes when the #1 spark plug fires. It look a bit like a pistol, so don't take one into the local Commonwealth Bank branch.

2) When you plug a consult into the stock ECU to check ignition timing does that mean what is set at the CAS is what it will show on the consult screen plugged into the ECU? Or is the only real way to see what ignition timing is sat at the crank by using a timing light? Because looking at the consult it shows 20 degrees BTDC.

What is shown by the timing light should match what the ECU thinks it is. You adjust the CAS to make them the same.

[PhilGTR]

1) What a timing light is or what that looks like??

A light that when hooked up flashes when the #1 spark plug fires. It look a bit like a pistol, so don't take one into the local Commonwealth Bank branch.

2) When you plug a consult into the stock ECU to check ignition timing does that mean what is set at the CAS is what it will show on the consult screen plugged into the ECU? Or is the only real way to see what ignition timing is sat at the crank by using a timing light? Because looking at the consult it shows 20 degrees BTDC.

What is shown by the timing light should match what the ECU thinks it is. You adjust the CAS to make them the same.

So you are saying that what i see with the computer saying 20 degrees may NOT necessarily be what it is set at the CAS until i check with a timing light to confirm? I read somewhere that a power fc for example may show 15 degrees but the CAS is not?

[PhilGTR]

I just opened my bonnet and checked the sticker under the bonnet with the engine running specs, when to change oil, air filters, etc and it said my base timing should be 15 degrees at idle. mines at 20 degrees, should it be put back to standard?

Also why is it that most people say its 20 degrees? its a 97 gtr

[Beer Baron]

it should be 20. the sticker is most likely wrong. It would have been fitted at compliance. knuckle heads.

[PhilGTR]

it should be 20. the sticker is most likely wrong. It would have been fitted at compliance. knuckle heads.

Really? I thought the sticker was part of the car when it was built from the factory? My old GTR had a similar sticker too.

[Beer Baron]

nah, they are fitted at compliance. and some compliance shops just use a 'one sticker fits all' mentality. cars like silvias etc do have 15degree BTDC base timing, but I can promise you hand on heart RB26DETT run 20 degrees.

if someone has believe the sticker and set your car with 15 degree base it will run a shitload better when you crank it back to 20.

[mad082]

of course it will run better at 20. i run the missus pulsar at about 21 degrees and it is 15 stock. runs tons better. i ran my gts-t at over 20 and it ran brilliantly.

[Beer Baron]

yes, but the point is factory base timing for a GTR is 20.

[mad082]

yeah i know. unless it is an auto, and then it's 15 degrees.

[Beer Baron]

mate there is no RB26DETT fitted with an auto box. lol. so no, it's not 15 degrees. never has been, never will be. It's 20 degrees base. for all GTRs.

[NewKleer]

So you are saying that what i see with the computer saying 20 degrees may NOT necessarily be what it is set at the CAS until i check with a timing light to confirm? I read somewhere that a power fc for example may show 15 degrees but the CAS is not?

correct, the ecu assumes that the CAS is set "correctly", which means the ecu reads the correct timing. if its not set correctly, eg its set 2 degrees advanced from where it should be, the ecu will ignite 2 degrees earlier (but it is still thinking its igniting at same timing value as it does normally).

hence, only way to confirm timing is set correct is with timing light (and locking the ecu into locked timing mode so it reads steady 20 degrees instead of jumping around)

[wrxhoon]

mate there is no RB26DETT fitted with an auto box. lol. so no, it's not 15 degrees. never has been, never will be. It's 20 degrees base. for all GTRs.

You tell him BB , stock base timming for Rb26 is 20 degrees. Your ecu bases everything on the fact that you have set your base timming at 20, if your base timming is set at 15 she will underperform .