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Discussion Starter #1
Just thought I'd report, though I really don't have a lot of info to offer. I was going to try to do before and after G-tech runs, only to find the road outside my neighborhood that I use for the purpose torn up for utility work. Conditions were about the worst imaginable: 100 degrees, super high humidity w/ heat index >110, very windy. Anyway, the procedure is quick and painless and you shouldn't get charged over $50 for it.

As for differences, I had to rely on the ol' butt dyno and haven't driven it a whole lot yet. Something DOES feel different, but it's hard to describe; it is subtle. There does seem to be a bit more in the low-mid rpm range and I haven't driven it hard yet. Only took it to redline once.

I have to admit, I don't know much about the concept behind this adjustment. Can someone explain how it works and what it's supposed to do? If I can feel something down low, it shouldn't take away anything in the top end, right?
 

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I also forget the tech aspets. I also bumped the timing on my old GTI 3 degrees. Back in the olds days with mechanical fuel injection.
 

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In essence,if the initial advance(as in the old distributor days )was 10degrees BTC(before top dead center) you have had it changed to 12 degrees BTC.Increases low and mid,will make it more sensitive to octane particularly at top end and remember your entire curve is moved up 2 degrees...so if 32degrees BTC at 6000rpm it will now be 34.Drive it hard,you will feel it more responsive to throttle input,off start and all the way along which is why Geofx and I find it hard not to enjoy it.Will be more detonation sensitive to bad gas or altitude than before...but within factory range.

Surprised they charged you!
 

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Discussion Starter #4
brnjugfx45 said:
In essence,if the initial advance(as in the old distributor days )was 10degrees BTC(before top dead center) you have had it changed to 12 degrees BTC.Increases low and mid,will make it more sensitive to octane particularly at top end and remember your entire curve is moved up 2 degrees...so if 32degrees BTC at 6000rpm it will now be 34.Drive it hard,you will feel it more responsive to throttle input,off start and all the way along which is why Geofx and I find it hard not to enjoy it.Will be more detonation sensitive to bad gas or altitude than before...but within factory range.

Surprised they charged you!
Thanks for the explanation. I haven't done enough pulls off the line to notice it there, but DO feel the difference all along the powerband. The stock base timing was 15 degrees, moved up to 17 degrees. 2 degrees is the max the Consult II will allow it to be adjusted. So what does it exactly mean that the entire curve is moved up 2 degrees?

Oh, and I said YOU shouldn't get charged more than $50 :wink:
 

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Simply that the 2 degrees is not just added at idle,it lifts the whole curve up 2 degrees.(which is the ECU max+/-)
 

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MustGoFastR said:
Oh, and I said YOU shouldn't get charged more than $50 :wink:
Did you use the old "crappy gas mileage" excuse and try to get it done for free? :p

MustGoFastR said:
Conditions were about the worst imaginable: 100 degrees, super high humidity w/ heat index >110, very windy.
Man, I'm glad on vacation in the SF Bay Area now... 8) On the down side, I'm stuck with my mom's '95 Plymouth Voyager... :roll:

brnjugfx45 said:
Drive it hard,you will feel it more responsive to throttle input,off start and all the way along which is why Geofx and I find it hard not to enjoy it.Will be more detonation sensitive to bad gas or altitude than before...but within factory range.
Agreed. I noticed the increased throttle response off start than
anywhere else. :)
 

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OK, I gotta get this done. Thnx fellas
 

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Discussion Starter #8
Well, after a bit more driving this morning, That subtle something is still there and feels pretty good. The explanation I got from my service manager suggests that advancing the base timing initiates spark a bit sooner in the combustion chamber during the upstroke of the pistons. This takes full advantage of the higher octane fuel by providing more complete combustion. Better combustion = more power. Odly enough, the first thing I noticed yesterday (but didn't mention it b/c I wanted to be sure I still felt it was there this morning) is that the engine seems to have a slightly deeper tone to it. Makes sense, I guess; different explosion in the chambers, different sound.

At any rate, I'd say this adjustment is a no-brainer if you exclusively use premium fuel.
 

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Any downside of doing this?
 

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Oddly,premium fuel burns slower,which is how it avoids detonation,cheaper,low octane burns faster.Firing earlier on the up stroke is summed in the language BTC(before top dead center).Pre-ignition is when the chamber is so hot that the fuel explodes on compression without the spark and pushes hard on the rising piston(bent rods).Detonation is the knock as the firing spark literally rocks the piston on the up stroke and causes damage over time,or just that fatal once.We now have knock sensors to cut back timing when they detect knock. Turbo/Super motors are prone to both because of the super compression of the gases and the high air temp of the compressed air...more than you needed to know!

There is NO downside other than altitude and less than premium fuel
 

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Discussion Starter #11
Can't see any. My service manager said gas milage might go down slightly, so I'll keep an eye on it.
 

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MustGoFastR said:
Can't see any. My service manager said gas milage might go down slightly, so I'll keep an eye on it.
My gas mileage stayed about the same after the timing change, which is roughly 13 MPH. :cry: One of the reasons why I got it changed was to see whether I can improve gas mileage. Oh well, at least I got a "boost" in performance... 8)
 

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Discussion Starter #13
More info. on this:

After a couple of days of driving, I could still feel that subtle difference in the car that I just couldn't put my finger on. Thing is, I couldn't really decide if that something was good or not. The couple other people that have had this done make it sound like there is a major improvement, but to me, it's very subtle and I couldn't swear that it was an improvement. SO, I had to be sure.

First, I e-mailed Adam at Crawford to get his take on the whole thing. I hunted up a thread on My350Z that I had previously forgotten on the topic that both of us had posted to. In that thread, he clearly said DO NOT advance your timing; you'll make better power with stock timing. I followed up with a series of e-mails, which I will add to this post later (it's on my computer at home). The short of it is that it's his experience that stock timing is better (they have a ConsultII and have played around with it quite a bit). Also interesting was some info. re: '03 ECU maps vs. '04. As I said, I'll get this info. up later.

I still wanted proof for myself and my trusty G-Tech hasn't failed me yet, so last sat morning, I went out first thing and made some runs before it got too hot (my times are at home as well, so I'll add those in later, too). After my runs, I swung back by the dealer and had them reset my timing to stock, after which I immidiately went back out and made more runs. My times went down .1-.15 sec 0-60. Well, the numbers don't lie, so right back I went and had them advance it again, mad a couple more runs and immediately picked that .1-.15 sec back up. End of story; timing stays advanced. Now I'm running a fresh tank of gas through and will note any changes to gas milage.

During this process, I figured out exactly what that elusive difference was that I was initially unable to identify. With the timing advanced, I was not feeling as big a "kick" in performance at around 4k rpm that I used to feel. It's this that made me wonder if the timing advance was really doing me any good or not. Well, according to the times, it obviously is, so I surmise that the advance has provided a bit in the low-mid RPM range, making the previous jump at 4k less apparent. I also noticed a bit of throttle tip-in lag on takeoffs, but I think the tranny may just need to re-adjust a bit, as it does not happen in manual mode and has been getting less aparent over the last few days.

So, to sum up, as of right now, I officially give this adjustment (at least for '03 cars) the MustGoFastR seal of approval. If I find out anything else, I'll be sure to post.
 

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MustGoFastR said:
I hunted up a thread on My350Z that I had previously forgotten on the topic that both of us had posted to. In that thread, he clearly said DO NOT advance your timing; you'll make better power with stock timing. I followed up with a series of e-mails, which I will add to this post later (it's on my computer at home). The short of it is that it's his experience that stock timing is better
I wonder if anyone's played with the VK that way? I'm gonna get my timing advanced next week when I get my 22.5K service.
 

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Already did,do it without hesistation!!The bigger motor feels it and it ain't subtle!
 

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Also interesting was some info. re: '03 ECU maps vs. '04. As I said, I'll get this info. up later.
Hey Must., what's the word on the '03 vs. '04 differences? Did your timing advance change your fuel economy or did it remain the same like mine?
 

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Discussion Starter #17
GeoFX said:
Also interesting was some info. re: '03 ECU maps vs. '04. As I said, I'll get this info. up later.
Hey Must., what's the word on the '03 vs. '04 differences? Did your timing advance change your fuel economy or did it remain the same like mine?
Here is the info. I got from adam re: the timing advance:

ADAM: On the dyno the increase in timing across the board did not make that big of a difference. As you said the tip in when you first get on throttle suffered and the overall feeling was not impressive. My timing and fuel is all custom now with my ecu, even for tip in. My car really has a great feel to it. Every car that we have advanced the timing on, has been reset to 0. No one here really likes it either. All the 04 cars use a better timing map and should not be bumped. 04 cars are also harder to mod because of this.

ME: As I said, I have an '03, so when you say "All the 04 cars use a better timing map and should not be bumped.", does that mean there might be some benefit to me?


ADAM: No the 04s use a more tweaked tune. It is less forgiving and runs more lean. So if you do add lots of mods to an 04 and/or bump the timing you will be running more lean than say an 03 car with same mods. The car likes 13-13.5, anything too much more or less it loses power.

ME: I went out one morning and did some G-tech runs with it advanced before going back in and having them reset it to stock. I did more runs after the reset and it turned out the car was actually .1-.15 sec quicker to 60 with it advanced (consistently, too, and I test under very constant conditions). Went back, had them advance it again, did more runs and the gain was immediately back, so I still have it advanced at this time. Thoughts?

ADAM: Yeah, the timing advance does help some cars for sure. Having been thorough all these flashes I just know that the timing map moves around based on many factors. Simply moving the bar up 2 degrees did not always help my situation. On some highly modded cars it even made the thing ping a little especially on 91 octane. I know that my timing map is just how I like it. I am having some issues on tip in right now, but I think it has a lot to do with my light flywheel and momentum. Make no mistake when I really launch the car with a clutch slip above 2000 rpm my car will flat out haul!
Just finshed off that tank of gas today. Milage stayed exactly the same for me.
 

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What Fun!!!
I had to go back and figure out who Adam was..ok,I did that.3 FX's did this and 3 FX's felt an improvement!
You had your A/F checked and it was alittle rich in the 13's which is typical since manufactures want to protect from lean outs and emissions are not done at WOT.Cars are set to be around 14.6-7
Perfect for power A/F has always been 12.5 edginging toward 13.That chemistry has not changed!And better to be just lean of perfect I will be interested to see if you get to a better/leamer A/F when you do some exhaust work

Distraction aside..It Works!
 

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Discussion Starter #19
Oh, yeah, sorry about that. Adam = VandyZ from Crawford. Yeah, most guys that get their ECU reflashed have the A/F set to 12.5 accross the board at WOT and around 14.7 for normal driving. If I ever get my cats and Y-pipe done, the TS reflash will be the last performance item on my list.
 

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I wonder what the difference is in the 2004 A/F mixtures. Are they already set at ~12.5 stock (max power) vs. the ~13s for the 2003s? If in fact the 2004s run leaner already what would advancing the timing make them more susceptible to issues if running less than premium gas (e.g, 87 octane)? Or are the anti-knock sensors good enough to retard timing? Hey brnjug, what year is your FX?
 
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