Timing advance?

[SilverGTV8]

I have a quick question, I wasn't able to locate a thread on it

Anyone know how much if it all the Diablo Sport supplied predator timing advance is?

I was poking around before i installed and I went into the advance and it read zero and allow me to increase it and decrease it. The scale seemed to indicate that was the zero point. (40 retard to 10 advanced)

If not can I safly adjust it up without being on a dyno? I already am running premium gas in the car.

 

[propellerhead]

I don't think DiabloSport is gonna publish that. They consider it proprietary. *shrug*

BTW, that's 40% retard to 10% advance of the timing curve that the Predator Performance Tune loads. That's not degrees.

I have a thread on here about adjusting timing with the Predator. I am watching for points where the EEC pulls back the timing. I think that's more reliable than listening for knocking or pinging.

 

[kah9911]

If they are points the 0 your at now is the stock 10* of timing. The +10 would be 20*.

 

[SilverGTV8]

Well as I had pointed out to me and researched the Predetor supposedly is a % advance.

So 1%= 3.6 degrees (100% = 360degrees) So a 10% advance= 36degrees advance. So why would I not use the tuner over the timing adjuster like everyone says.

You are saying that the factory advance is 10degrees? So people buying timing adjusters are only adding 4degrees? or adding 14 degrees on top of the 10?

 

[propellerhead]

It's not a percentage of 360 degrees. It's an increase or decrease of the base timing in the tune you are modifying. Spark advance is calculated dynamically and is based on RPM, LOAD and a few other factors like IAT, MAF, etc. A 10% advance in the Predator means at any given point along the RPM vs LOAD vs all other factors curve, the resulting timing will be 10% more than what it would normally be. This only applies to the 2k-4k and 4k-7k RPM bands.

This is different from the traditional method of setting timing. We would use a timing light or mechanical timing adjuster to set the idle RPM timing. When you stomped on the gas pedal, the timing would increase by a preset amount. We had no control over how much it increased under throttle. The only control we had was the idle RPM timing. The timing curve was fixed. The mechanical timing adjuster adds a bias to this curve. You bump up the idle RPM timing by 5 degrees and it bumps the entire curve equally by 5 degrees.

These are two different approaches to adjusting the timing and sometimes it's hard to seperate the two. The Predator applies a gain. The mechanical method applies a bias.

 

[SilverGTV8]

I see now. The Predator litature is not that clear on the actual function. I figured the timing adjust works like a timing light versus dist. cap rotation. Just wasn't in complete understanding of the Predator's method. It makes more sense then my 1%=3.6degrees, I thought that was kinda steep and didn't make sense on the back end(retarding side) of the scale. Thank you for the clarification.

Now I just need nice weather, nice sterch of road, my laptop, and the predator.

Ohh I have a good one. can the car power the predator for download to a PC or do you need to use a power supply to do the download.

 

[propellerhead]

I know what you mean. The first night I had the Predator, it was raining. When I punched it on an onramp to the freeway, the back end of my car kicked left really hard. I backed off right away since I didn't want to end up in the ditch.

The car can power it. I just need a budget laptop with a 9-pin serial port so I can do data streaming while I drive.