Making a turbo spool sooner?
I'm running a 7875 tnetics with a 1.15 a/r and a 3 inch pipe pre turbo. Cam in mine is a 238/242 .605/.605 112lsa I do believe. I would say it is your tune. I'm no expert by no means but it seems the way your timing curve is layed out could play a pretty big roll in how it spools. Someone correct me if I'm wrong.
Makes 1# of boost instantly if you stab the throttle. That was with the 6 speed, with the th400 it is the same really.
I could dog it in 5th at 50mph and it would make 5#+ at 1500 rpm passing traffic
Makes 1# of boost instantly if you stab the throttle. That was with the 6 speed, with the th400 it is the same really.
I could dog it in 5th at 50mph and it would make 5#+ at 1500 rpm passing traffic
You are on E85, you can throw a good bit more timing at it.. especially out of boost. Keep the timing low at peak torque but after that you can ramp it back up.
ive got 14* in mine at peak torque and 19*-20* up top. 11.0 AFR
ive got 14* in mine at peak torque and 19*-20* up top. 11.0 AFR
It almost looks like burst knock, but I have disabled those tables. I don't know what could be causing it as the timing isn't that high and the fuel looks good. Also it is random and doesn't do it every time.
What is your timing when out of boost? Also I'm not sure where my peak torque is at yet, haven't put it on dyno yet. (will probably in the spring) But i will start adding timing after 5250rpm as HP is always higher at that point. However I only run the engine to 6000rpm to help the rods hold together.
What is your timing when out of boost? Also I'm not sure where my peak torque is at yet, haven't put it on dyno yet. (will probably in the spring) But i will start adding timing after 5250rpm as HP is always higher at that point. However I only run the engine to 6000rpm to help the rods hold together.
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From: Norn Iron
I am running 13 degree's of timing (started low as I am initially dialing in ve), and I start pulling timing once boost starts to build, and I put it into PE mode about the same time. BTW, I have it kick into PE mode around 12psi map pressure as my map reads 12.3 psi with key on engine off, so anything above 12.3 is boost pressure.
Does anyone have an example of their spark timing and fueling as a guide? If someone could post a snap shot of their logs I'd like to see how fast their turbos spool, and the timing and fueling when it does. I will have to get my other computer later to post a snap shot of the logs I took this weekend.
13 deg of timing off boost ? no wonder it's a slug. And then you retard it even further ?
E85 needs more timing, that will make a huge difference. I don't want to give you bad information so I'm only speaking for my own set up is I have the tune so that it looks like it's naturally aspirated until I'm at least at 3-4lbs of boost.
Whats the timing under 100kpa??? 13 degrees is on the low side you could throw 15 at it wot with e85 but that has nothing to do with spool up. Start with a timing table like your na car would be under 100kpa and ramp down. What afr's are you seeing when your trying to spool???
just noticed you do have na tables............
just noticed you do have na tables............
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If I stab it off idle it goes positive pressure right away and builds quickly from about 1500rpm and is full boost (12-14lbs) by 3k rpm.
Like others said my timing ramps down after 110 kpa but doesn't go down to 18* until about 3-4lbs.
Cruising/part throttle timing is in the high 20s low 30s and is in the low 20s at 110kpa still. Ramps down like others say as boost comes in.
Here is a screen shot of a log. Problem is I was wearing boots and thought i was at wot but was really at 90% for a bit. Still at 90% throttle it is at 5000rpm an only making 4psi of boost. (12.3 is what map reads key on engine off). Maxes out at 21psi, so only 7psi of boost that run.
I have attached the tune I was running when logging this. I have since gone and increased the spark timing at lower air flow to hopefully help spool better and will log tomorrow. I also leaned out the VE table as it is very rich right now.
I have attached the tune I was running when logging this. I have since gone and increased the spark timing at lower air flow to hopefully help spool better and will log tomorrow. I also leaned out the VE table as it is very rich right now.
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From: Norn Iron
Well I am using psi instead of kpa, because i can look at psi and instantly tell how much boost i have where kpa isn't as intuitive. Plus I'm a stubborn american, we use standard units not metric! 
Also at sea level you should have a psi reading of 14.7, but I live at high altitude thus why it is 12.3. This is what the stock map sensor read, and I verified it against others as well.
Also at sea level you should have a psi reading of 14.7, but I live at high altitude thus why it is 12.3. This is what the stock map sensor read, and I verified it against others as well.
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From: Norn Iron
It would be a lot easier to view the log screenshot, if the scaling at the side was more sensible.
ie timing from -40 to 40....when the range being used is actually only say 5 to 30, or are those bits not changeable ?
Also, only viewing items of interest at this time.
But it does still look that as soon as you go full throttle ( or near it ) timing flatlines at what I presume is 13deg ?
As for boost....it looks like the log is the car accelerating through some gearchanges. Maybe in the lower gears, there isnt enough load against the engine for it to make boost. Which could point to overly large turbine in some way. Or just a combo that is slow to spool ?
Boost only really rises a bit once into a higher gear with more load against the engine.
ie timing from -40 to 40....when the range being used is actually only say 5 to 30, or are those bits not changeable ?
Also, only viewing items of interest at this time.
But it does still look that as soon as you go full throttle ( or near it ) timing flatlines at what I presume is 13deg ?
As for boost....it looks like the log is the car accelerating through some gearchanges. Maybe in the lower gears, there isnt enough load against the engine for it to make boost. Which could point to overly large turbine in some way. Or just a combo that is slow to spool ?
Boost only really rises a bit once into a higher gear with more load against the engine.
I change the scaling so it is easier to read.
you are correct the timing is flat lining at 13 degrees. It is hitting 13 degrees at 2psi boost.
This quick run was punching it from a stand still running it about a quarter mile.
It also isn't the greatest since i wasn't 100% throttle initially....
BTW, thanks a ton for checking out the logs. I appreciate it.
you are correct the timing is flat lining at 13 degrees. It is hitting 13 degrees at 2psi boost.
This quick run was punching it from a stand still running it about a quarter mile.
It also isn't the greatest since i wasn't 100% throttle initially....
BTW, thanks a ton for checking out the logs. I appreciate it.
Now I'm being greedy and going to ask your opinion on the following screen shot. Once in a while when I punch it I get some KR. This one is pretty small, largest I have seen is 1.5* KR.
Why is this? I have removed all burst knock but still get this.
Why is this? I have removed all burst knock but still get this.
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From: Norn Iron
80-100% throttle will probably make almost no difference at all anyway, especially at lower rpm.
As for anything you're seeing as far as knock. Knock sensors listen....just because they hear something and it flashes up on your screen, doesnt mean it is knock.
But determining what is and isnt, goes back to basic tuning techniques and listening for knock via "det cans" or similar, so you can fine tune any filter settings within the ecu that set thresholds for what is and isnt detonation.
I'm not familiar with HPT so cant comment how good or bad the factory setup is in this respect.
As for 13deg of timing at 2psi, that is wayyyy too low.
2psi is still in around n/a territory for the most part.
Even if you considered a 2deg less timing per psi boost over base n/a tune, that is still a large amount of timing to drop.
So you're losing a huge amount of performance/spool/power from such low timing, especially during spool.
At such low boost pressures, you could safely be running in the 12.x AFR range during spool, and even at 6-7psi I wouldnt be too worried about running 12.0:1 AFR at full boost.
Although once over 5psi, aiming for 11.x will do little harm and always be safe.
As for anything you're seeing as far as knock. Knock sensors listen....just because they hear something and it flashes up on your screen, doesnt mean it is knock.
But determining what is and isnt, goes back to basic tuning techniques and listening for knock via "det cans" or similar, so you can fine tune any filter settings within the ecu that set thresholds for what is and isnt detonation.
I'm not familiar with HPT so cant comment how good or bad the factory setup is in this respect.
As for 13deg of timing at 2psi, that is wayyyy too low.
2psi is still in around n/a territory for the most part.
Even if you considered a 2deg less timing per psi boost over base n/a tune, that is still a large amount of timing to drop.
So you're losing a huge amount of performance/spool/power from such low timing, especially during spool.
At such low boost pressures, you could safely be running in the 12.x AFR range during spool, and even at 6-7psi I wouldnt be too worried about running 12.0:1 AFR at full boost.
Although once over 5psi, aiming for 11.x will do little harm and always be safe.
