C6 e40 TT SD-tune hesitates in spool

[n_brio]

My Setup

2005 c6 m6
TTiX 3" dp
SD tune 2,5 map sensor
bosch motorsport 1435cc @ 4bar
return fuel system dual walbro 450 one turn on in boost
Btr custom turbo cam with spring+
stock bottom end

The car runs greate in primary VE But when the turbo spools it hesitates for a moment and then after 4000 rpm it runs like a train.

When it hesitates it sounds like its pulsing out air (dumping air)


LogFile 17.hpl
Tune orginal cab med patch 25.hpt

[5FDP]

You have a huge dip in the VE table once you enter boost. Look at how high the VE numbers are up to around 105 kpa, then look at the numbers once your reach over 105 kpa in the boost VE. Timing nose dives into the negative and you lose all power.'

Log the MAF fail status to make sure it's in speed density, sometimes with settings of 0hz and 0hz won't work on GEN 4 computers. Try 2hz and 1hz, then remove the MAF channel from your logs to prevent data skewing.

Your IAT table is also removing 8 degree's of timing and causing it to run at or below 0 degree's of timing at WOT, you would want to adjust that table so it doesn't take away all your timing.

[schpenxel]

Two things

1. That's got to be one of the worst VE tables I've seen in a while. Should be a smooth transition from regular to boost VE and the whole table should be shaped like a torque curve, peaking at peak torque for a given pressure..

2. It's literally running 0* of ignition advance @ WOT... You've got a high octane timing table in low single digits and IAT is pulling another 8* out on top of that.. no wonder it isn't going fast. It gets up to a whole 5* there at one point... this thing might scare you once you fix the ignition timing

It's also dropping down to 0.70 lambda right when you get on it.. and judging by the crazy spikes you have in the regular VE table I'm not surprised.

Needs work. Give it more timing and fix those VE tables.

[n_brio]

Now i see it in the other computer i did not see it in the laptop i have mess with the decimals so i did not see the different.

I did have a torque shaped curve in the beginning (i did copy a aps tune from the repo) but it did float away like this in the end

[n_brio]

schpenxel: should i add more ignition in the high octane table during tuning ve or should i modify the IAT Base Spark table during tuning?

[schpenxel]

schpenxel: should i add more ignition in the high octane table during tuning ve or should i modify the IAT Base Spark table during tuning?

Both IMO.

What fuel are you running? If 93 I'd throw some torco or something in there to bring the octane up, if anything kills that motor it will be knock.

You can run pretty close to N/A ignition timing at low boost, 1,2 maybe 3 psi.. it's when you get up to 8, 10, 15psi you want to really be careful with timing because cylinder pressures are so high at that point. Here's a tune from a buddy of mine with a rear mount turbo 2005 C6

He was running E85 though so not much risk of knock.. I would not go anywhere near as crazy as he went but his stock motor survived this timing and 19 psi of boost

KYLE 102915timing.hpt

[n_brio]

I run e85 👍ok i will try to add some timing

[schpenxel]

Woohoo, E85 wins. Yeah you'll be fine to add some timing then IMO

[veee8]

Woohoo, E85 wins. Yeah you'll be fine to add some timing then IMO

Yeah about 20* more!

[07GTS]

if u want a high octane spark table to look at my file here will be a good starting point for e85 and my PE BE should be safe also or u could go a little richer at first https://www.hptuners.com/forum/showt...w-when-rolling
also try 29.1 in your stoich table to multiply by 3 for your injectors on e85, also your IFR is constant but the offset/volts/vac is for a set pressure they should both be setup for your setup type set pressure or vac referenced.? can divide fuel density to help the fuel usage closer to normal, and IVT terms need to be changed to suit also since stoich was changed

[schpenxel]

Yeah about 20* more!

I wouldn't go QUITE as far as this dude did.. I'm surprised it survived up top to be honest, but you can go a bit more for sure IMO

[n_brio]

schpenxel:

I did use your friends tune and did start from there. Now the car is an animal! still have to tune the timing.

But i do get some knock retard around 400 rpm at 9* timing. i did not think it was possible to get knock whit e85

Thank you!

[n_brio]

schpenxel:

I did use your friends tune and did start from there. Now the car is an animal! still have to tune the timing.

But i do get some knock retard around 4000 rpm at 9* timing. i did not think it was possible to get knock whit e85

Thank you!

[schpenxel]

Doubt it's real, but, again... I wouldn't run 100% his timing, pull some out.. he's crazy to run THAT much

Yeah highly doubt that knock is real to be honest but see if it's consistent

[n_brio]

i did 12* as max timing for now. maby a get greedy in the end of the summer and turn it on more

[n_brio]

what was the max boost your friend had? and what was the hp number?

[schpenxel]

18-19 psi, lol.. I told you he was crazy

You can run more than 12* at lower boost/RPM's, just don't get crazy at high boost and especially around peak torque..

Never had it on a dyno but he outran a few 800rwhp centri setup C6 corvette's no problem

[n_brio]

Im doing small changes all the time and my logs makes my map strange. Between shifts it goes lean between 105 kpa to 153 kpa making the map make a big jump.

Is PE ramp 2.0 to slow?

log.jpg

[schpenxel]

I mean you can't close the throttle and not expect boost to drop off for an instant.. The lean spike sounds more like a transient fueling issue to me.. I never have been able to totally get rid of it on mine (also an E40)

If you were using a slower wideband I doubt you'd ever even see it on the logs

You could setup a filter so your graphs don't pick up places where throttle is under 90% or whatever, that might help filter some of it out

PE ramp isn't the problem

Yeah your VE table is pretty weird looking.. it def shouldn't go down as boost increases