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Basic question about ignition timing

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Hi, I am still getting things setup with logging via Uprev on a Nisan VK45 engine (it's a long story but it's a new rom for uprev) and recently they got ignition timing to log but I am not sure if the timing logged is accurate. It is reading mid 60's BTDC at idle (which to my limited experience seems high) through to mid 90's when driving. I was expecting it to be less than 20 at idle.

So my question is what would be a common range for ignition timing over a rev range of 1000 to 7000 rpm for stock petrol engine?

While you might see 45 deg BTDC for low manifold pressures and mid-high RPM, typical values for normally aspirated engines while cruising and WOT running are usually between 15 - 35 deg.

As noted in another thread the Nissan ECUs might be using a burn-time instead of ignition advance so those values might be in a different units than deg BTDC.

Yeah, that would make some sense, I did know about that but for some reason assumed the logging would be in degrees.

The values used in the ignition timing tables however max out at about 72, well short of mid 90's that I see logged.

While the Uprev ignition tables are in an unusual unit that doesn't relate to actual advance, at least on the models we dealt with, the logged advance was actual ignition advance in degrees BTDC. The numbers you've quoted above don't feel very realistic at all but I can't tell you what is going on here sorry.

Yeah, Ok, I'll submit another support request to them. Thanks.

Definitely not actual ignition advance in degrees BTDC firing.

Yes, I have put in another support req with UpRev adn they have already responded to tell me it will be a couple more weeks before they will be able to look at it. :(

It's frustrating as it has been a few weeks already, I sent the original rom dump on 8th May for them to port to their system.

Hey Rob, just a heads up that HP Tuners are now supporting a lot of Nissan vehicles via their new MPVI2 interface. I haven't tuned using it so I can't comment on how complete their definitions are but it may be a viable alternative option.

Thanks, I've asked the question of them so will see if HP support this setup, it looks promising.

VK45 isn't listed, but VK56 (US market truck) is. They might be able to do something for you.

yeah, they list the V6 versions of the Fuga, and several Nissan and Infinity models with versions of the VK engines, the 56 and 50, so wait and see. ECUTEK doesn't do any Nissan V8's

But as I have already shelled out a fist full of money to UpRev I am hoping they do the right thing and fix the issues. They have support for the VK45DE in the Infinity M45 which is the American version of the Fuga 450. So I am pretty sure it is just minor issues with getting the logging to work correctly and with all available sensors.

Unfortunately HP Tuners said they do not support vehicles not already on their list. One imagines that would make it hard to increase the number of vehicles they support.