Give some details please..

5 wire Grounding kit
350z Pipe / Stillen High-Flow
JUN Flywheel on it way!!!
Crawford on its way!!!
Best 1/4 14.299 @ 97.99

 

In all probability the computer will compensate for the mechanical error , An upgrade or change to the ECU would be more of a logical solution.

 

In a nutshell, advancing the ignition timing allows the pistons to "squeeze" the fuel/air charge for a couple of more degrees of crankshaft rotation before the spark plug fires.

This results in a few more horsepower, as long as the amount of advance isn't too much, which could cause detonation/ping.

 

I think you said that wrong...

If you advance timing, spark plugs fire sooner. Pistons will be farther away from top dead center. The fuel charge will have longer to fully combust, increasing power transfer. You are correct: Too much advance may cause detonation. If you advance timing, the engine runs leaner, and therefore hotter. Too much heat may cause detonation.

If you retard timing, spark plugs fire later. Pistons will be closer to top dead center, or even past top dead center. More retard causes an engine to run cooler. Too much retard may cause a loss of power, as some fuel leaves the cylinder through the exhaust port before it fully combusts. Engines with added forced induction and/or N2O retard timing to keep the crank spinning in the right direction...

'03 G35 5AT Sedan- Garnet Fire/Willow
SSR GT1s & Bridgestone S03s, Eibachs

 

Nope, you've got it backwards. If you ADVANCE your timing, what you're really doing is allowing the piston to complete more degrees of crankshaft rotation, before the spark plug fires.

A common mod to the old 5.0L Mustangs was to advance the timing from the factory setting by about 3 degrees. This gave a noticeable improvement in power/acceleration. Retarding the timing would only slow you down.

 

My guess is, in our G35s, advancing the timing will do nothing. Our ECUs monitor the detonation sensor constantly to provide best performance under all conditions. If you used higher octane fuel, your ECU would probably advance timing on its own to take advantage of the higher octane. By the same token, if you used lower octane fuel, the ECU would retard timing as needed to prevent detonation.

'03 G35 5AT Sedan, Garnet Fire/Willow
18x8 SSR GT1/Bridgestone S03/Eibach

 

bullseye is right. The more 'advanced' the timing, the sooner the plug fires.

2004 Black 6MT

 

Excellent timing. Thank you for your support. (Is it too late for me to run for Governor of the great State of California?)

Of course, advanced timing results in an earlier firing spark plug. And retarding ignition timing does not necessarily cause the engine to make less power. In today's cars, the timing is adjusted dynamically by the ECU, cylinder by cylinder, to produce optimum performance for all octanes, all temps, all barometric pressures, all throttle positions, etc. I'm pretty sure the ECU adjusts timing for advance or retard at every cylinder on every compression stroke. With all the onboard sensors and computing power, it would not surprise me... It sure beats the heck out of fooling with a distributor, huh? Take care.

'03 G35 5AT Sedan, Garnet Fire/Willow
18x8 SSR GT1/Bridgestone S03/Eibach

 

Correct bullseye - on my last car (Audi S4) I had diagnostic software I could use to monitor individual timing retard on each cylinder due to knock control. What's interesting is some chips on the S4 took advantage of higher octane fuel and some didn't. The ones that didn't simply had conservative maps that wouldn't advance beyond a certain point (and on 93 octane you would never approach knocking). Another chip "rode" the knock sensor by running timing to the very edge. The latter chip made the most power on higher octane. The question is how much octane will Infiniti's timing program take advantage of (based on how much it's timing program will advance to the point of knock)

2004 Black 6MT

 

Good question...

Once upon a time, I drag raced my '95 Maxima (now well and truly deceased) as a casual hobby. One day, I asked one of the regular track workers out at the Memphis Motor Sports Park from how much octane my car could derive benefit. In other words, would my ECU advance spark as far as the knock sensors would permit, or were there set parameters within which my car's ECU operated, no matter how high the octance rating of the fuel?

Now, I do not know if this person actually knew what he was talking about. Nor do I know how the ECU in my '95 Maxima functioned, compared to my 2003 G35's. All I know is, he responded immediately, confidently, and directly: My engine would probably derive maximum benefit from 95-96 octane fuel, and that an octane rating higher than that would probably not result in higher performance. In other words, an even mix of my 93 octane gas and their 100 octane unleaded gas was about the best mix I could work with.

Even so, I tried using octane boosters, and/or higher mixes of 100:93. In retrospect, I'd say the guy at the track was right...

If our ECU's operate anything like the ECU in my Maxima, I'd say there are set parameters within which our ECUs will adjust ignition timing. After all, Infiniti engineers probably did not contemplate owners running on race gas for day-in, day-out driving about town.

That's my best *guess*. Anyone else want to take a shot?


'03 G35 5AT Sedan, Garnet Fire/Willow
18x8 SSR GT1/Bridgestone S03/Eibach

 

ok... timing of 16 means that the spark plug will fire when the cam for each cylinder is 16 degrees past dead center. If you advance the timing you will fire the spark plug when the air and gas are compressed more because of the increased amount of travel of the cylinder. I may be wrong but I am 99% sure that I am not. My statement means that bullseye, g35 madman and hitman are all correct.

 

Learned fuel adjustments made by our ecus change air to fuel ratios to maximize efficiency for the fuel burned. It takes more 87 octane per unit of air to combust with the same force as 93 octane with less air. This is why lower octane polutes more and is bad for high performance engines.

Ignition timing is a setting that is in the base maps of the ecu and once adjusted applies to everything the ecu does. Just like changing idle rpm, if you set the timing to plus two it will stay that way unless changed externally. The only time that timing is pulled is in the event of engine ping or air to fuel ratios being too lean above 4500 rpm when the ecu changes to an open loop code for WOT.

Subsequently breather mods are seen to be counterproductive for some people due to ping and the leaner ratios above 4500rpm. When the open loop is reflashed and coded to set parameters using tables based on mods and diagnostic inputs, some people will see massive gains in horsepower and torque. I recommend osiris/cipher for na and in the future for fi as they are developing a new version.

Hope this helped,
Will in VA

 

By now this might seem funny seeing as how I am talking to people who asked this question in 2003... guess I shoulda checked before I posted. Either way maybe someone will find this useful!

 

Haha, I love these arguements. I'm not even going to touch the arguement about the basics of timing. But from my knowledge and according to the shop foreman of the Infiniti dealership, 3 degrees advancement from the factory specs should give you noticeable changes.

 

I have ciper and I think I can only advance timing by 2 degrees... they may be able to send me a reflash that changes the base by +1 and then I can tweak it by +2 with cipher...