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Discussion Starter #101
Just got into work work ripping up the back roads, car never missed a beat. No throttle cuts, also I am suspect that the "compressor surge" noise I was hearing was actually the bypass valve opening to help regulate boost as I can no longer hear it. It sounded just like comp surge but if you look below you can see where the bypass vlave can be used to correct overboost.

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Just reviewed the log, mostly the last one in your log, and PR maps are related to the cut for sure 100% based on where it cuts at due to rpm, iat, boost, barometric pressure, pressure drop maps, and now your posted PR map that I did not have before. See that it fixed the cut so guess my gut was right or maybe it was just a lucky guess on my part ;-)

Here is a shot of just before your car cuts throttle

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Here is a map on the bottom that you're likely missing that will multiply the PR map you have based on the iat in °C. As you can see it will lower your PR numbers with higher iat by quite some margin. Also an OEM PR map above it.

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Now that this is out of the way you may want to work on fueling/EGT, cooling off that IAT, ECT, and other parts of the tune before proceeding much further if you want the engine to live longer.
 

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Discussion Starter #103
Yeah IATs are the next on the list. Also help get egts down. I'm probably going to take it easy and get a water/meth kit next month and try distilled water first and see how that does. I would get a different intercooler but I really like how clean the stock setup is and how it doesn't block the radiator.
 

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Let me know as I can help you in all areas ;-)

Also just want to add that this last post you made makes you brighter than most VT owners out there that mod their car. Nothing against the avg VT owner but the avg IQ when it comes to modding for power is low and they rely way to heavily on marketing when it comes to mods and rely on poor info and data. But here again, lots of misinformation in the community.
 

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Here is a map on the bottom that you're likely missing that will multiply the PR map you have based on the iat in °C. As you can see it will lower your PR numbers with higher iat by quite some margin. Also an OEM PR map above it.

View attachment 105290

Now that this is out of the way you may want to work on fueling/EGT, cooling off that IAT, ECT, and other parts of the tune before proceeding much further if you want the engine to live longer.
Not tryng to derail this but, is this saying that with IATS at about 86*F the stock tune is pulling around 1-1.5 psi? And IATs at 130* F it pulls around 3.5 psi???
 

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At 86 IAT the pressure ratio is cut to 95.1% of the pressure ratio map. At 122 IAT the pressure ratio is cut to 87.9% of the pressure ratio map. In other words if IAT were even hotter the boost and power would have been cut sooner than it was at 17 psi in his tune.

On top of that the tune will pull copious amounts of ignition timing with higher IATS and higher ECT.

Which is why I stress cooling mods such as water/meth injection, thermostat, radiator cap, and better coolant. It falls upon deaf ears most of the time.....
 

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At 86 IAT the pressure ratio is cut to 95.1% of the pressure ratio map. At 122 IAT the pressure ratio is cut to 87.9% of the pressure ratio map. In other words if IAT were even hotter the boost and power would have been cut sooner than it was at 17 psi in his tune.

On top of that the tune will pull copious amounts of ignition timing with higher IATS and higher ECT.

Which is why I stress cooling mods such as water/meth injection, thermostat, radiator cap, and better coolant. It falls upon deaf ears most of the time.....
I wont add any more comments on this out of fear of distracting from the HPTuners talk but, make a solid post and get it stickied. I think everyone could find it useful. The current discussions are a bit scattered and it takes a while to sift through them.
One stickied post with some hard evidence, steps, and results would be really cool.
 

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Never be scared to comment. Nothing was distracting from the thread as it does pertain to the tune to help better understand what's going on.

This thread will likely be 2-3x this long before the OP has what I'd consider a decent tune. He has tuning experience with similar ecu so can you imagine the cluster someone would have with little to no experience tuning? Even if trying to do it with a how to guide they'd have a cluster as they have no clue what's "safe" or "normal" in a datalog for given parameters, mods, fuel, etc, and that can easily be put into a how to guide.
 

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Never be scared to comment. Nothing was distracting from the thread as it does pertain to the tune to help better understand what's going on.

This thread will likely be 2-3x this long before the OP has what I'd consider a decent tune. He has tuning experience with similar ecu so can you imagine the cluster someone would have with little to no experience tuning? Even if trying to do it with a how to guide they'd have a cluster as they have no clue what's "safe" or "normal" in a datalog for given parameters, mods, fuel, etc, and that can easily be put into a how to guide.
Alright fine. lol. So here is a question birthed from a substantial amount of ignorance,
That "Comp Ratio Correction Factor - IAT" map seems simpler than I would expect. Are those hard threshhold (0*, 10*, 30*, 50* C)? Like at 29.9* C are you still at the 0.987 correction level then 30*C you jump down to the 0.951 correction level? If so, can that map be expanded?

I have personally been putting a lot of effort into trying to figure out how IAT's affect power. Here we see how they change boost targets (by up to ~3.5 psi!). Obviously they affect timing advance as well. If a chart like this is available for timing advance I personally would love to see it.
 

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No hard thresholds as the maps blend with others touching it according to the parameters at the time. If that needs explanation I can.

IAT can change max boost quite a bit and so can elevation as seen in the map already posted. Keep in mind the pressure ratio map is also based on pressure drop map of the intake and intercooler/charge air side along with the iat correction and barometric pressure the ecu outputs before coming to a final number.

Here is a map that pulls ignition timing based on coolant temperature on the left side/ rows and IAT for the columns up top.

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Then factor in the knock sensors detect knock across all cylinders and is constantly adding and subtracting timing per cylinder and grossly based on sensor activity and many other maps in play before coming to a final ignition timing.

In other words you can take a car and make a 250 whp dyno pull wait a few minutes and make a 247 whp pull at the same exact temperature parameters but there was a little more heat in the engine somewhere that made the knock sensor pull timing and make less power. But wait 15 min where all temperatures the same as pull 1 and it make 250 whp again. These cars will tend to make within 1% power pull after pull if everything is the same pull to pull. That's how good the ecu is when the tune is dialed in.
 

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I think the blending makes sense. Which is good.

Honestly from that table it doesn't look like most normal conditions would result in timing being pulled ( I should probably log coolant temps though so I can look back and see what they are normally at for me... :) )

Are there other tables like that for IATs? I had assumed that more timing would be pulled than that but I guess knock could be the other factor related to IATs I hadn't considered.
 

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Knock sensor activity from many factors is a wild card for sure that most have no clue about. I know over 184 ECT and over 104 IAT the tune is pulling ignition timing already. It's not hard to get a car over these numbers at all especially without cooling mods. It's actually already pulling timing by the time coolant gets into the 170's regardless of IAT. This is one reason why I suggest and offer 160°F thermostat to the community and better coolant with radiator cap. Cheap insurance that adds power and safety.

Keep in mind the term boost weather. Cool days a car makes more power because IAT and ECT stay cooler. It can be boost weather on a 100°F day if the same car has a 160°F thermostat, better coolant, radiator cap, and proper setup water/meth injection kit pulling 40°F + out of the IAT. Let that sink in.....
 

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Curious to see logs of any updated tunes since you can pull to redline now without throttle closure. Look to be holding ~18 psi when you let out.
 

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Discussion Starter #114
Not tryng to derail this but, is this saying that with IATS at about 86*F the stock tune is pulling around 1-1.5 psi? And IATs at 130* F it pulls around 3.5 psi???
Looks like
Never be scared to comment. Nothing was distracting from the thread as it does pertain to the tune to help better understand what's going on.

This thread will likely be 2-3x this long before the OP has what I'd consider a decent tune. He has tuning experience with similar ecu so can you imagine the cluster someone would have with little to no experience tuning? Even if trying to do it with a how to guide they'd have a cluster as they have no clue what's "safe" or "normal" in a datalog for given parameters, mods, fuel, etc, and that can easily be put into a how to guide.
Yeah feel free to discuss anything related to the tune logic regaurdless if it is using a different configurator. Either way it is all the same, we are all just trying to better understand how to get HP to do what we want it to. A guide probably won't come around for several months at best. There is still a lot of experimenting and tuning left to do. Like trdtoy says if you have any questions ask and I will do the same and we can all work together.
 

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@hairpinperformance: Re the PR map that you have, a few things to consider.

Keep in mind they will be multiplied by the other map I provided based on iat and in a blended manner which you should be familiar with. So this means the PR/boost it will cut at will increase with lower iat.

Also know that it references model maps for intake air restrictions which the restrictions get higher with rpm and boost ie air flow.

Same goes for model maps for pressure drop across the intercooler/charge side. It uses model maps for pressure drop which increases with air flow.

Also I provided the OEM compressor map earlier so you know roughly where the surge line is of the turbo. Keep that in mind when setting up your PR map.

Once you have your map setup for current barometric pressure go ahead and calculate out for the other barometric pressure areas of the map and be sure not to exceed the PR of the compressor. This will help with elevation if you ever take the car there. Many VT current and past tunes will suffer power loss at elevation due to this map not being setup properly. Some tuners just put the numbers way high which will not let it cut at all which means damage to the engine or turbo itself which has happened as well.

I know the next hurdles you'll get to after this point but I'll see if you get there first before addressing to keep this thread clutter free as possible.
 

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Discussion Starter #118
@hairpinperformance: Re the PR map that you have, a few things to consider.

Keep in mind they will be multiplied by the other map I provided based on iat and in a blended manner which you should be familiar with. So this means the PR/boost it will cut at will increase with lower iat.

Also know that it references model maps for intake air restrictions which the restrictions get higher with rpm and boost ie air flow.

Same goes for model maps for pressure drop across the intercooler/charge side. It uses model maps for pressure drop which increases with air flow.

Also I provided the OEM compressor map earlier so you know roughly where the surge line is of the turbo. Keep that in mind when setting up your PR map.

Once you have your map setup for current barometric pressure go ahead and calculate out for the other barometric pressure areas of the map and be sure not to exceed the PR of the compressor. This will help with elevation if you ever take the car there. Many VT current and past tunes will suffer power loss at elevation due to this map not being setup properly. Some tuners just put the numbers way high which will not let it cut at all which means damage to the engine or turbo itself which has happened as well.

I know the next hurdles you'll get to after this point but I'll see if you get there first before addressing to keep this thread clutter free as possible.
This morning I took some logs on the way to work. I need to get them posted. I'm on my phone now and work has been hectic. But long story short I dropped my max overboost kpa back to 20 and started getting some cut after 6k so I increased it until I had zero cut. Nonetheless this just further emphasizes how important it is that I get the iat under control and get my pr limits dialed it. Like you said I could potentially use this as it was designed for engine protection. Let's say I run out of water injection and IATs get high my pr limit can help prevent engine damage. Additionally I need to like you said do some calculation and figure out if I'm at the surge limit of the turbo. All of this I can figure out. I just need the time. I'm wrapping up my 97 NA turbo Miata build at the same time.
 

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You need to get rid of overboost feature altogether. It leads to inconsistent and unpredictable power and boost. Once you tune the car it actually makes the tune more unsafe IMO due to this.

Yes keeping the iat in check is crucial in these cars as they'll pull power on any warm or hot day just getting into the throttle good once or twice or stop n go driving etc.

Would love to see some logs when you get a chance.
 
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