CullenJ76

iTrader: (3)

I just adjusted the timing on my SE-R and it got me wondering...
I'm thinking of doing a write-up on timing advance. I'd probably try using different octane level gases(including race fuel) and the timing advance of each one to get an Idea of the differences. Anyone interested or tried this already? Thanks

Stephen Max

iTrader: (59)

You sure you're in the right forum? We Maxima owners have no way to adjust timing, except send the ecu to JWT.

MrGone

iTrader: (30)

no no no. You VQ owners have no way to adjust timing, except for to send the ECU to jwt or have consultII adjust it.

We VG and VE owners on the other hand....

feel free to make a write up. I have a feeling a majority of the people on this sit have no idea about adjusting timing and such. Dont forget the different types of triggers, oh and make sure you include how to adjust points (ok joking about the points).

Stephen Max

iTrader: (59)

Sorry, I forgot about you guys. I've got VQ blinders on. <== me

CullenJ76

iTrader: (3)

my fault. I should have been more clear in my original post.

What I'm doing a write-up on is not adjusting the timing(can't do that without a consult I or II).
I'm talking about reading the total retard and advance of the timing not adjusting.
I plan on using a few different levels of octane, including race and using my timing light to get an idea of timing at wot,idle, etc. and the affect of different octane levels on the timing.
Sorry about the confusion.

CullenJ76

iTrader: (3)

I'll eventually(next month or so) be doing this on a '94 VE auto(including adjustment procedure), and a 2k2 6spd.

MrGone

iTrader: (30)

Cool! Feel free to ask my any questions if you need. IIRC the bolts are 13mm, but I dont completely remember.

Just out of complete boredom and excitement about engine timing and a mix of not going to sleep last night and spending the whole night BSing with other maxima.org guys...
change the and to or because timing cannot be both retarded and advanced. For example with the VE, its stock timing is 15*BTDC. Retarded would be 14.99* and later, while advanced would be 15.01* and earlier.
Again just out of pure boredom (and procrastination for writing an essay), Octane is simple the gasolines resistance to burning, which equates to its resistance to detonation. I can tell you right now the gasoline octane will not retard or advance the timing, What will happen is depending on the motors state of tune, the knock sensor might detect pinging or knocking then retarding the timing, but on an engine in decent condition (spark plugs in range, everything working good and no excess carbon buildup in the cylinders) will not show you any difference in timing because of the knock sensor when idling. The engine has to be under load, so it will be hard for you to monitor this with a timing light while driving.

The only thing the higher octane gases are used for is to prevent pinging/knocking/detonation which cannot be detected under a no load condition. In our experiements with DaveBond007's car, he was running Texaco (iirc) 92octane when we advanced his timing. He had a resistor inplace of the knock sensor, and we could barely squeeze out 16* on his car with that knock sensor. My car has been running 20* and a resistor for a about the same time, the only difference being I use Arco gasoline. Running race gas will not get you anything unless you are have really finetuned your car when supercharged or on nitrous.

Testing for stuff at WOT vs idle and partial throttle with the car in neutral generally will not work because they car is under no load. It's kind of like why if you rev your engine at a stop light it sounds really pathetic (unless you can get that nice vacuum going with a really quick jab of the pedal), while when your out pulling the gears it sounds soooo much louded and more agressive. Learning about how the VTC's work will teach you about this really quickly, or have you scratching your headlike a caveman

Oh yeah, and if you try going WOT with a timing light on, the lights normally turn off after ~3000rpm or so

Just imagine, my mustang had distributor shaft play so the timing would always be changing, so it would never idle below 1000rpms, (or 1200rpm) and would stumble when you stepped on the gas. I had the points set sooo well Nascar would have used them if they used them . In the end out went all the stock stuff and in went a full MSD ignition . Next up, rejetting and tuning your carb hehehehe, I wish

CullenJ76

iTrader: (3)

where do i start? Yes timing advances and retards constantly, you are thinking of btdc timing at idle or something.
The "and" is there because when you are using a timing light it will be at BTDC when at idle(under no load btw) and as you rev timing increases, when you let off the gas the timing will actually go below "where you have your BTDC timing set at"(retard), and then go to normal once regaining idle.
I know what octane his and consequently how it burns/causes reaction.And yes, testing the total timing advance will work under no load I just did it in my se-r and maxima(just for the hell of it). I've never seen a timing light turn "off" after 3000 rpm's and i've been messing with nissan's for 8+ years(not to sound like a know at all, cause i really am just a diy mech. like the rest of us). Thanks for the info though

MrGone

iTrader: (30)

the 3000rpm thing was just what I experienced with my VE, could be the timing light though.

and yeah your right. about how it fluxuates.
oh yeah, on the VE, to get base timing, unplug the purple connector below the throttle body area, and the grey connector on the throttle body.

CullenJ76

iTrader: (3)

Isnt the procedure for the ve is the same for the vq: unplug the TPS, run at 2k rpm under no load and rev 2-3 times above 3k rpm to make sure the ecu locks the timing and heat up oxygen sensors, keep idle around 800 rpm, and then test timing

SteVTEC

CullenJ76

iTrader: (3)

thanks for the reply
I thought this might attract you, and figured you had already done this