Timing Tables under boost

[RR|Suki]

For those who tune their own cars:

Back when I was first doing a tune for this car I had no real frame of reference, I asked for advice a few places, and one response I got was when boost comes on to have the timing come in low and then build over time. I got an explanation about load along RPM and some other stuff. Made enough sense and I didn't have easy access to a dyno, so I've always run pretty tame timing, and used the explanation given to me as a guide to the progression of timing.
eg. current progression from 2500rpm to 6K =
7.5, 8.5, 9.5, 10.5, 12.5, 15.0
Soft sure, but the car still goes just fine.
If I was left to my own devices I would have made the table in a similar way to how I'd do it on my old 74 mini. I would have N/A timing up to boost, then I'd start backing off the timing from there. IE 2500 and up would look more like 20, 19, 18, 17, 16, 15. Not necessarily those numbers, but progressing down rather than up. Heck maybe even just hold at 16 when the boost comes in.
Just something that has been going though my mind, so I guess all I'm wondering is how others are handling timing in high load boost areas.
low stepping up, stepping down, holding or something else completely.

I feel like I could gain a bit in the middle, just trying to decide how to attack it.

[Zack]

For those who tune their own cars:

Back when I was first doing a tune for this car I had no real frame of reference, I asked for advice a few places, and one response I got was when boost comes on to have the timing come in low and then build over time. I got an explanation about load along RPM and some other stuff. Made enough sense and I didn't have easy access to a dyno, so I've always run pretty tame timing, and used the explanation given to me as a guide to the progression of timing.
eg. current progression from 2500rpm to 6K =
7.5, 8.5, 9.5, 10.5, 12.5, 15.0
Soft sure, but the car still goes just fine.
If I was left to my own devices I would have made the table in a similar way to how I'd do it on my old 74 mini. I would have N/A timing up to boost, then I'd start backing off the timing from there. IE 2500 and up would look more like 20, 19, 18, 17, 16, 15. Not necessarily those numbers, but progressing down rather than up. Heck maybe even just hold at 16 when the boost comes in.
Just something that has been going though my mind, so I guess all I'm wondering is how others are handling timing in high load boost areas.
low stepping up, stepping down, holding or something else completely.

I feel like I could gain a bit in the middle, just trying to decide how to attack it.

First determine max load so you arent adjusting tables for nothing.
Then just add timing in small increments row by row, making sure to drive it around under all conditions to make sure no pinging is evident.

Never fail, when you are in 4th with a locked converter and you give it gas to the point where it almost downshifts is where you will have the detonation.....and after all your hard work adding it in you will probably have to take it out in those spots.

[RR|Suki]

First determine max load so you arent adjusting tables for nothing.
Then just add timing in small increments row by row, making sure to drive it around under all conditions to make sure no pinging is evident.

Never fail, when you are in 4th with a locked converter and you give it gas to the point where it almost downshifts is where you will have the detonation.....and after all your hard work adding it in you will probably have to take it out in those spots.

That's my current attack plan. I use sniper, and their data logger has never worked for me. So I bought a locked XCal 2 and I'm gonna try to get that thing to work for logging. I must say it really doesn't like windows 7 so far, or it hates my ECU, haven't put much effort into it yet.

Also I have to say, the tables in the sniper stuff are very strange sometimes. The air charge correction factor is def set to 1.9, but the load side on the spark tables don't adjust. And I swear the scan gauge never goes above 98 (maybe it can't)
You can change the x,y values in the software, but that just scales the values to the same number of points, so 1.9 moves to the place of 1.0 etc. Either way I've always kept it only going to 1.0, and I've just gone with my ears as far as making sure there wasn't too much timing. Once I get this XCal working I think I'll finally be able to see what is really going on. Something tells me I'm gonna find that I've been running 12.5 up top the entire time and the middle has been basically empty :rolleyes:

[MM_BKK]

Which table are you working with? Borderline or MBT?

Better yet, do yourself a favor and just take it to a professional tuner and have it tuned. It will be the best money you'll have spent for your car. I gave up on my Sniper Delta Force. I got the SCT PRP and I thought I had it pretty well tuned on my own until my tuner pointed out how my tune was flawed. Those guys tune dozen of cars a month and you're not going to be out tuning them. They may find problems with your set up that you didn't know you had.

My tuner fixed me up and gave me my final tune so I can play with the shift/lock schedules.

[RR|Suki]

Which table are you working with? Borderline or MBT?

Better yet, do yourself a favor and just take it to a professional tuner and have it tuned. It will be the best money you'll have spent for your car. I gave up on my Sniper Delta Force. I got the SCT PRP and I thought I had it pretty well tuned on my own until my tuner pointed out how my tune was flawed. Those guys tune dozen of cars a month and you're not going to be out tuning them. They may find problems with your set up that you didn't know you had.

My tuner fixed me up and gave me my final tune so I can play with the shift/lock schedules.

Borderline table

I do ultimately want to get a pro to tune it for me, however it's a matter of cash and time to head out. Once I have a few hundo to spare I'll likely take it to Lidio (but I've been saying that since 2005 :lol:)

[TooManyFords]

As I do my own tuning, here is a picture of the spark table in my BigStuff3. I tune it to N/A specs and then reduce spark as boost and timing increase. Because this can be done real-time, I have the screen up in the drivers seat and listen for knock as Zack described. Only difference is I can tweak it right then and there. What you cannot see in this snip is the black oval that shows exactly what cell(s) are being used to calculate spark at any given moment. I change the cell that has the highest percentage of coverage, and only by a degree (or tenths) as needed.

I should make a video of the screen while out driving it so you get the idea.

http://www.cvmusclecars.com/picture.php?albumid=4&pictureid=1253

[RR|Suki]

<-- can't see :o

[TooManyFords]

My pic??????????????

[RR|Suki]

My pic??????????????

Yep, just a blank space for me

[TooManyFords]

png image. i recommend google chrome.

[TooManyFords]

cuz you know better! :D

[RR|Suki]

I run chrome, looks like I can't see links to MM.net galleries without being a contributing member etc. Seems like that is it.

[TooManyFords]

I run chrome, looks like I can't see links to MM.net galleries without being a contributing member etc. Seems like that is it.

Ok, I moved the image to my forum and changed the link. You should be able to see it now.

[RR|Suki]

Ok, I moved the image to my forum and changed the link. You should be able to see it now.

Thank you sir, that's more like I was thinking it should look. as a reference here is mine:http://i570.photobucket.com/albums/ss143/VTRauder/Sparktable.jpg?t=1274931999
pains me to think of how much I'm missing in the mid range

[TooManyFords]

Interesting. Is that the default table for the Marauder PCM? If so, then it must be the difference between having 10:1 compression and my 9:1 and the ability to run more spark.

/shrug

[RR|Suki]

Interesting. Is that the default table for the Marauder PCM? If so, then it must be the difference between having 10:1 compression and my 9:1 and the ability to run more spark.

/shrug

no that's the blower tune from a few years ago that I'm still running. The default N/A table is a good deal different. I run lower comp too, and not much boost. That timing table just kinda got put in there since I didn't know what I was doing, the car went pretty fast on it and it's not gonna knock, so it kinda just stuck with me the last few years here. I can feel that it's missing something so it's been getting on my nerves. Made me decide to actually get off my ass and figure it out.

[Zack]

Suki, what is the value of the global spark adder?

[RR|Suki]

Suki, what is the value of the global spark adder?

currently 1

[Zack]

currently 1

Is that a plus or minus 1?

You can always add it there first to eliminate a lot of work designing a new table.

[RR|Suki]

Is that a plus or minus 1?

You can always add it there first to eliminate a lot of work designing a new table.

plus 1, I'll try that thanks.

I think I'm gonna take it to the track with the extra boost and see what kind of times I run before jerking around with it too much. I finally got them to fix my template so that I now finally have the ability to move my rev limit above 6200, so at the very least I'll be able to have the car shift properly now.