Does my H.O. timing look alright?

[chris07ss]

Numbers-wise. I had my car re-flashed by a reputable tuner a few years ago, but have since then picked up HPT and began making changes to the car myself.

One thing I can't seem to get right is a proper timing table. It didn't seem right to me, so I hand-smoothed it, backed off the low RPM and load timing a few degrees, and added 1* to the WOT areas.

I'm just not sure if it looks right. When the car is under load, say when I shift from 1st to 2nd around 3k, the car just feels like it's pulling timing and is bogging out or something. I can hear a bunch of ticking/hissing while it's under load, and trust me when I say there is NO exhaust leak. Really, it feels OK until you get into the throttle and throw some boost at it. *shrug*

I attached my latest file, which is on the car now, and what I had on there before. If anyone can give it a once-over and throw me some pointers, I'd buy you an e-beer or something. I really am lost at this point, lol.

Thanks in advance. Really appreciate it.

PS: Car is a 2007 LSJ.

[omega_5]

I don't know what to tell you, besides.... start over.

A good timing table should be smooth, with gradual transitions. Your timing table looks pretty rock on the one end, with an undesirable plateau on the other.

Depending on your mods, a good idea, is to start with the stock timing, and smooth the hell out of it. Flash it in, and log for knock, then adjust accordingly. Just remember to keep it smooth.

[chris07ss]

Thanks. I was certain that it should be smooth, that's why when I saw it I panicked. Smoothing it out (from what it was) has seemed to help during light/moderate throttle, but under heavy load it's still dumpy.

As for mods, I have a 3" pulley on the M62, 42# injectors, airbox mod, midlength header, catless resonated DP, and 2.5" catback with OEM res and muffler.

I have the "stage II for 07" timing table downloaded from the repository. I suppose I'll start with that and make the proper changes. What do you think about that idea?

I attached a copy of the Stage II tune below. Also, is there anything else from the S2 I should re-work into my current tune?

Thanks, btw.

[chris07ss]

Scratch that, I think this stock 07 timing table looks better.

Thoughts?

[chris07ss]

This "stage II retune" from the repository looks pretty good as well, although I don't like how it has so much up top. Either way I have to make changes so maybe I'll start with that, seeing as how I have basically the same mods.

http://www.hptuners.com/customers/tu...ownload&id=883

[omega_5]

Use your stock timing table as the base.
Highlight it all... and hit 'smooth area' about 6 times, to get a nice smooth base.

Are you running any cooling mods?
You can probably add about 2* across the board to the base... but be careful, and log for knock. If it is showing signs of being too much timing for your mods, then back it off.

[chris07ss]

Do these cars take a certain amount of time to re-learn certain paramaters after reflashing the VCM several times?

I smoothed out a stock timing table, and when I loaded it and drove around, the car knocked like crazy between 2 and 3k while under boost. I thought the sound of the air rushing through the header/flexpipe was knock, but no. This is a loud, raspy metallic sound.

I flashed back to the timing/tune I had before, and it wasn't any help whatsoever. The car almost stalled twice on my way home and it idled like it was about to run out of gas at times.

I don't get why it's knocking so badly between that load range all of a sudden, even with the tune I had on there before that was perfectly fine and didn't make such a horrid noise. It sounds like a baseball card in the spokes of a bicycle, just really fast.

[omega_5]

Only fuel trims require time to be re-learned.... and that's only if you reset them.

If the sound remains even after switching back, there is a good chance it is a mechanical issue, and not a tune issue. Smoothing the stock timing table should not affect the car in such a way.


On a side note... why is your stoich set to 14.3?

[csementuh]

Sub'd for results.

I have my stoich set to ~14.4 to account for E10 gas. That may be why his is setup that way.

[omega_5]

Sub'd for results.

I have my stoich set to ~14.4 to account for E10 gas. That may be why his is setup that way.

Ah.... that would make sense.

I tend to forget that, cause most gas stations up here don't blend their premium fuels.

[csementuh]

Ya the fuel around my area is terrible... The 93 E10 is piss water with a splash of ethanol. The variations from one station to the next are bad as well. I'm dying to run some E85 but the closest station is about 25 minutes aways. Hopefully that changes.


What's wrong with using the S2 table as a base and then adding some timing in there? What is the general rule of thumb for what ranges to add timing in to build up to your max timing? .80g/cl and 4096rpm and up, etc?

I had what was considered to be a 'good tuner' tune my car a couple years ago on a really old setup, and the timing table he put in my tune had a huge plateu as well. I'm dying to get a good timing reference as my TVS needs some timing lol. Currently running 18* top end on 93. I weirdly get some occasional low end and mid range KR though. I'm almost positive it's false knock though caused by my exhaust rattling though, as if I pull out slowly and the exhaust rattles, there is a bunch of KR hits.

[omega_5]

The Stage 2 spark tables are fine if you don't have any base tables built up.

A good start, is to take the stock or S2 table, the smooth the hell out of it to get rid of the harsh transitions (select all, and smooth selection about 6 times).
Then log it, and remove knock.
From there, you can increase you timing as you see fit.

As far as your knock in the low-mid range... that's the nature of a supercharged engine. It loads up the boost quick enough that it can cause tip-in knock, or trip the burst knock system.
There are a variety of methods to deal with those issues... each have been criticized in some form.

[csementuh]

Thanks for the advice. I had a table that I was running and modding by it was a little too steep, and had a little bit of a flat area top end. I'm mainly concerned about how to best get the engine to max timing. I've been told to roll in 16* by 4000, and get to max timing by redline. Dumping in a bunch of timing top end though and smoothing seems to make the timing map too 'steep'. How does one for instance do a good map running 20-25* degrees of timing top end without having a peak or valley in the map aka keeping it smooth? Raising the timing too much makes a divit where the stock map plummets the whole way back down to 14.5* from the low airload values of 40+*. Basically I'm asking which area limits to increase? I mean surely you cant just increase the stock map by 10.5* all over for 25* max can you?

[omega_5]

I'll point out a few key places on the ignition map.
- the low RPM high load area; draw a line from 0,0.36 to 3840,1.36. Anything down and left of that area should be left alone. This is a chugging area, and is pretty knock prone... you should rarely be in this area anyways.
-the 'cruising' area; draw a line from 1792,0.08 to 4352,0.36, then all the way to redline. This area should be set for optimal cruising efficiency, then smoothed in to the rest of the map.
-anything under ~2200rpm; this is the idle-ish area. This should be a blend of the chugging area, and the low rpm cruising area. Don't be concerned about too much timing here... just optimize... you're not winning any races in this area.

Everything else is fair game.
Set your timing... optimize... blend well.

[csementuh]

I'll point out a few key places on the ignition map.
- the low RPM high load area; draw a line from 0,0.36 to 3840,1.36. Anything down and left of that area should be left alone. This is a chugging area, and is pretty knock prone... you should rarely be in this area anyways.
-the 'cruising' area; draw a line from 1792,0.08 to 4352,0.36, then all the way to redline. This area should be set for optimal cruising efficiency, then smoothed in to the rest of the map.
-anything under ~2200rpm; this is the idle-ish area. This should be a blend of the chugging area, and the low rpm cruising area. Don't be concerned about too much timing here... just optimize... you're not winning any races in this area.

Everything else is fair game.
Set your timing... optimize... blend well.

Fantastic! That's what I was looking for, thanks.

Now the areas that should be kept relatively stock for good efficiency, should those not be increased by a factor of 2* like you suggested for the stock or S2 table? Should those areas not really be increased much since they're idle and cruise areas and not WOT areas?

[omega_5]

Now the areas that should be kept relatively stock for good efficiency, should those not be increased by a factor of 2* like you suggested for the stock or S2 table? Should those areas not really be increased much since they're idle and cruise areas and not WOT areas?

What I do for the 'cruising' area, I did a trial and error at different cruising speeds to find an optimal timing for fuel economy. I tested between 45mph and 70mph cruising speeds. Above 70mph, I simply blended it into the stock table, as you rarely cruise at 6000rpm.

For idle, I left the timing stock from 0rpm to 400rpm above my cold start idle. So for example... if the cold idle is set to 1150, leave the timing relatively stock up to the 1536rpm column.
Above that, start to blend the chugging area, the low idle area, and the cruising area. As mentioned earlier, you can blend it up to 2200... or even higher if you want.

Basically, WOT only applies to the angular strip form the middle of the map to the lower right corner.
Do a log of what cells you hit when you do a WOT pull... only advance timing around that area, then smooth it into the other three controlled areas.


Give me until this afternoon, and I'll post up a few images, detailing the boundaries of the control areas, and the WOT strip.

[csementuh]

Thank you that certains helps me, and hopefully the OP!

I'll have to work up a doctored timing table and then test it out on the car. Do you recommend setting the low octane timing table to the high octane table while testing so the PCM doesn't blend the ranges and you run too little timing?

[omega_5]

Thank you that certains helps me, and hopefully the OP!

I'll have to work up a doctored timing table and then test it out on the car. Do you recommend setting the low octane timing table to the high octane table while testing so the PCM doesn't blend the ranges and you run too little timing?

No... the low octane table is a safety net.
It only blends if it senses knock.... when it's done being tuned, there shouldn't be any knock.
So, really... the actual timing value doesn't really matter... as long as you're removing knock and preventing it from knocking on the next run.


I should note, though... that the only time you put the high octane table in the low octane map, is when you fail the MAF, as it reverts to the low octane table by default.

[csementuh]

OK great. I've also read that a good low octane table is your dialed in high octane table minus 4 degrees all over?

[omega_5]

OK great. I've also read that a good low octane table is your dialed in high octane table minus 4 degrees all over?

I just leave smooth the stock table.
If you get a bad batch of fuel or something, it's better to pull a bunch of timing, rather than knock the engine into oblivion.