/\ post your timing map and well do a comparo

 

The OP actually posted my base timing map. Not too pleased by that, but, whatever.

As a datapoint, peak cylinder pressure at 350 g/sec of flow on the Renesis happens in 20° of crank rotation on 91 RON/MON. Since we want that to happen at about 15° ATDC...

 

I'm the OP and I don't have access to any of your maps so I can't see how you could possibly be upset by the map I posted ?

 

I meant the map posted above by SC-ed. That was in the materials made available to paying customers of the Calibration Seminar.

 

I see . Not too much given away . Or is there ......

Interesting to see what you do at NA peak loads . Same as what my tuner did with my 8 a few yrs back .

 

And people wonder why the most worthwhile services after a while can no longer be offered.

 

Thanks for posting this!

Anyone have any comments on the timing for this? I may consider using it...

 

He's running 4° ATDC at the torque peak and 10 PSI.
That is probably a bit too conservative.

 

Which is why I couldn't hand out any of the really useful stuff.
I'm sure someone recorded it, though. It'll end up on YouTube.

 

but otherwise it looks good? I'm a fan of being conservative... I will be primarily running on 91 octane as well.

 

She is covered in sores. And she is missing a leg. And she is dead.
Otherwise, she looks good!

Honestly, do you know what you are looking at? Did you compare the net timing of that Int-X display to the timing grid above? Do they even look remotely similar to you?

 

no, I don't fully understand what I'm looking at, which is why I'm asking you if it's a good map. Otherwise I wouldn't be asking at all.

 

Then, let me ask you - If you can't tell if it is a good or bad timing curve, why do you need to know? The information is of no use to you.

 

As I stated before, I'd like to use a new timing map for my car, and as a baseline for when it goes on the dyno for additional tuning. It's also a good way of learning how a good map looks versus something that doesn't, so that I can begin to make adjustments myself eventually. We aren't all experts here.

 

Well you saw what MM said earlier . His baseline map is back one page . Use that .

 

So much for posting maps and having discussions as to why or why not they are good

 

So much for reading comprehension.

I'm sure glad I explain stuff so it can get glossed-over and then people can complain that it wasn't explained to them.

 

whatever.

 

It is called mechanical advantage and brisance... timing in a vacuum cannot really be "good or bad", for example, some run more ignition with a richer AFR, some do the opposite.

The flame front propogagation varies with each degree of angle, as well as each molecule of fuel and air.

So you asking for a good timing map, would be like me asking for a good touch up paint for my car... sight unseen over the internet without the whole picture it is basically impossible to do. If you know the principles of it, then you can look at others maps and adjust them to your own car; but if you do not - then someone elses basemap is irrelevent to you.

That being said... if you want to play with fire then by all means go ahead. Here is the base map I typically use, on my turbo, east coast gas, east coast temperatures, humidity etc.... but if you think it is apples to apples, load it up and have at it.

 

Crap Kane beat me to it.

That's the primary issue with looking at individual tables and trying to make determinations without taking into account the rest of the tune. Even so, the effects at the tailpipe will not always be represented as a 1:1 ratio within the map itself. Intellectuality discussing the topic is always a plus but if you're expecting to post a map and be told "yes" or "no" then you're going to be disappointed.

 

All of your comments make sense, and I understood the concept when I was looking for something that I could use as a base map. The comment by MM, as quoted above, is not warranted as he's suggesting that the map is full of issues, and ultimately is useless.

Anyway - the main reason why I wanted to know if certain maps were 'conservative' or 'safe' is because my current ignition map doesn't really resemble any of yours - so I wanted something as more of a guide/aid to know that I'm on the right track in tuning.

 

There have been several maps posted - mine in the first post is probably the least conservative of those but if you look at kanes , mine and the MM base map in the previous page you will see that there are similarities and we know that all of them have worked well for each of us . So enough information is here for you to make a start with . The only one i wouldn't take much notice of is the one you quoted .

Does this help ?

 

Did I said somewhere it's your map?
No.
You did.
So don't blame me.
Sorry.

 

Updated 1st post

 

Think I'm starting to grasp timing, maybe

question though, it seems like there are large steps in all these timing maps. Just as an example take Kanes map on this page. At 4000 rpm the first 5 load columns are all at 43.5 degrees then the next column steps down to 40 degrees. Why is the timing not tapered down for a smooth curve? I see large chunks like this in all the maps shown.

Also what is the mathematical equation for determining timing? Google has failed me here. Seems like if you know peak pressure in the chamber, AFR, RPM, Load, spark duration and heat, you should be able to plug that into a calculation to determine the optimal spark timing?