[Dontbethatguy]

I'm at over 3,000' actual altitude. I installed my v2 harness this past weekend, and the car is a beast. My question is about the amount of boost with 100% torque values. I tried values from 90% to 100%, and it will make the same peak boost of right at 14 psi. As I raise the torque values, it brings the boost in at a lower RPM. At 90%, it was seeing full boost at about 5,100 RPM. However, with the values at 100%, it brings in full boost at 3,900 RPM. I think the altitude is simply limiting me on max boost since the turbos are so small. I know others have reported 15+ psi but I assume that's at a lower altitude and possibly with a different exhaust. My car is stock other than the ProCede. I did dyno the car, and it will show max boost on the dyno at 13.7 psi to make 375 RWHP and 434 RWTQ. I was pleased! This was on 93 pump gas, too.

Let me know what everyone else is seeing for max boost, particularly if you're at a higher altitude.

[XLR8MF]

Damn, good numbers for that altitude and no other mods. what octane?

[Dontbethatguy]

93 octane Chevron

[Driver72]

You are running 100% torque values while on 93 Octane pump gas???

In another post you reported seeing 14.5 psi peak boost on the road, but only 13.7 psi on the dyno.

Is your car a manual or auto??

I think you should be running at least 96 Octane if you are going to be running 100% torque values.

You should send Shiv an email about this, but in the meantime, I think you should lower your torque settings to about 95% while on 93 Octane.

Even though you are not seeing boost over 15 psi, running 100% on 93 Octane might not be advised.
But if you are NOT getting any limp modes, you maybe ok.

Again, consult Shiv.

[Dontbethatguy]

My car is a manual. I'm in my truck on the weekdays for work, so I doubt I'll drive it again until the weekend. I'm going to contact Shiv, though, to get his thoughts.

[335iheLLraiseR]

i never found this out, assuming you ARE running 100oct and crank everything up to 100% what is the max boost we should see?

[Kbueno]

I only saw high 14 with 100%/ 100 octane.

[daisy16905]

Shiv did mention that you don't want to go above 94% torque value with 93 octane.

Originally Posted by Driver72

You are running 100% torque values while on 93 Octane pump gas???

In another post you reported seeing 14.5 psi peak boost on the road, but only 13.7 psi on the dyno.

Is your car a manual or auto??

I think you should be running at least 96 Octane if you are going to be running 100% torque values.

You should send Shiv an email about this, but in the meantime, I think you should lower your torque settings to about 95% while on 93 Octane.

Even though you are not seeing boost over 15 psi, running 100% on 93 Octane might not be advised.

Shiv did advise that if you are running 93 octane the max he would recommend was 94% (per his testing with 91 / 93 octane).
But if you are NOT getting any limp modes, you maybe ok.

Again, consult Shiv.

[Tuned335i]

Assuming (and this is a big assumption) that there are no leaks in the system, as long as your peak boost pressure does not exceed 15psi, you're fine. Could the OP have a leak in the system that is preventing boosting above the numbers he's posted?

Call me conservative, but unless you have an accurate boost gauge properly installed and calibrated, I wouldn't experiment with 100% settings, even if I had only 100oct in the tank. The install/tune instructions say that if you want maximum power you can increase the %torque settings until you see 15.0 maximum psi. I don't know about you guys but I don't have the discretionary income to buy a new $14K engine (or whatever it costs), so conservative works for me

If the OP has a maximum boost of 14 or 14.5psi, then I would use the lowest torque setting percentate that will produce that boost and leave it there. But this is really a question for Shiv, and Vishnu is back tomorrow (probably with 200 emails and PM's...)

[turbotko]

I've been datalogging with the 12/29 2.0.2 the last couple of days. It really seems like there are too many variables to be able to accurately get an idea as to exactly how much boost the car is running. For example, I do all my datalogging runs from 2K rpm in 2nd and run all the way through the top of
4th gear. The datalogs will show 12.8 as peak boost one time, then on another run it will be 12.8 in 2nd gear, then make 14.9 for 2 seconds in 3rd gear before dropping to 13.0 at the top of 3rd, then only make 12.0 in 4th. On the 3rd run, it peaked at 13.2 and slowly tapered to 11.8 at the top of each gear.

My point is, the boost is all over the place with no rhyme or reason to it. I moved the torque settings to 94% and made 3 more datalog runs afterward, and the boost curves look the same. It never went over 14.9 psi, but wouldn't conistently run 14.9psi running max 13.4 psi most of the time. All runs were done at 40 degrees ambient at about 500ft above sea level.

It's fast enough at 94% for me although I'm not running anything close to 15 psi.

[e.n335]

Originally Posted by turbotko

I've been datalogging with the 12/29 2.0.2 the last couple of days. It really seems like there are too many variables to be able to accurately get an idea as to exactly how much boost the car is running. For example, I do all my datalogging runs from 2K rpm in 2nd and run all the way through the top of
4th gear. The datalogs will show 12.8 as peak boost one time, then on another run it will be 12.8 in 2nd gear, then make 14.9 for 2 seconds in 3rd gear before dropping to 13.0 at the top of 3rd, then only make 12.0 in 4th. On the 3rd run, it peaked at 13.2 and slowly tapered to 11.8 at the top of each gear.

My point is, the boost is all over the place with no rhyme or reason to it. I moved the torque settings to 94% and made 3 more datalog runs afterward, and the boost curves look the same. It never went over 14.9 psi, but wouldn't conistently run 14.9psi running max 13.4 psi most of the time. All runs were done at 40 degrees ambient at about 500ft above sea level.

It's fast enough at 94% for me although I'm not running anything close to 15 psi.

I have seen this behavior in my datalogs as well. In my understanding the boost should raise very early up to 13.5 - 14 psi ( @ 90 % ) and taper down slowly to 7-9 psi @ high rpms. I am far away from this.

2 Questions:

- Are my expectations wrong ?
- Can it be that my diverter valves are not working correctly ?

I will receive the Forge DV's soon, they are on the way already. I hope to see boost consistency improvements.

[CanadianTSi]

You see less Boost on the Dyno because it does not put as much load on the car as much as actually driving it.

[turbotko]

Originally Posted by e.n335

I have seen this behavior in my datalogs as well. In my understanding the boost should raise very early up to 13.5 - 14 psi ( @ 90 % ) and taper down slowly to 7-9 psi @ high rpms. I am far away from this.

2 Questions:

- Are my expectations wrong ?
- Can it be that my diverter valves are not working correctly ?

I will receive the Forge DV's soon, they are on the way already. I hope to see boost consistency improvements.

No, I think everything is working fine. It's just not like the normal boost curves I'm used to seeing on cars that only have mechanical control of boost through the wastegate. On the N54 the DME has control over boost and can raise or lower it depending on other variables. With a mechanical setup, you set it at 15 psi, and once full boost is in and stabilized, the boost will stay at 15 psi so long as the turbos can physically provide that pressure.

My biggest problem is that it's just not a flat graph of boost once full boost is in and stabilized. The boost seems to change from run to run without any rhyme or reason to it...........most likely it's the DME manipulating the boost to compensate for atmospheric conditions. I'm just afraid that my datalogs at 40 degrees outside might be below 15 psi, but on a 100 degree day the DME will increase the boost to prevent performance drop off due to higher intake air temps and might put it over 15 psi without me knowing it.

I'm just gonna set it to 94 percent, run some random data logs for the next couple of months to be sure it's under 15psi, then run more datalogs if the weather changes drastically (like this summer when it's hot).

[pikkashoe]

I spoke to shiv one time while I was at the track, If I recall correctly, for me running 100 octane, with torque settings at 100% he mentioned I would be at around 18 lbs of boost. But dont quote me on this one, Im trying to remember. Maybe he will chime in.

[ThomasMartin]

Originally Posted by pikkashoe

I spoke to shiv one time while I was at the track, If I recall correctly, for me running 100 octane, with torque settings at 100% he mentioned I would be at around 18 lbs of boost. But dont quote me on this one, Im trying to remember. Maybe he will chime in.

Hey Guys Happy holidays to everyone im back from vacation so first reply for the new year.

Im currently running 98% at high altitutde and im not seeing any boost over 13.5 PSI. Shiv told me we cant damage the turbos as long as our boost stays below 15 PSI so what im asking is why do the cars at high altitiude run fine at 98% torque settings with normal pump gas. Shouldnt we be getting knocking codes?

[Kbueno]

Originally Posted by pikkashoe

I spoke to shiv one time while I was at the track, If I recall correctly, for me running 100 octane, with torque settings at 100% he mentioned I would be at around 18 lbs of boost. But dont quote me on this one, Im trying to remember. Maybe he will chime in.

I've heard this before, but has anyone really seen 18+ psi running at 100%? If so, show a datalog, please.

[pikkashoe]

I dont have any datalogs, next time I go to the track I am going to run 100%, but I doubt I will be able to datalog it making runs down the track.

[down4it]

Originally Posted by TrevorD

I'm at over 3,000' actual altitude. I installed my v2 harness this past weekend, and the car is a beast. My question is about the amount of boost with 100% torque values. I tried values from 90% to 100%, and it will make the same peak boost of right at 14 psi. As I raise the torque values, it brings the boost in at a lower RPM. At 90%, it was seeing full boost at about 5,100 RPM. However, with the values at 100%, it brings in full boost at 3,900 RPM. I think the altitude is simply limiting me on max boost since the turbos are so small. I know others have reported 15+ psi but I assume that's at a lower altitude and possibly with a different exhaust. My car is stock other than the ProCede. I did dyno the car, and it will show max boost on the dyno at 13.7 psi to make 375 RWHP and 434 RWTQ. I was pleased! This was on 93 pump gas, too.

Let me know what everyone else is seeing for max boost, particularly if you're at a higher altitude.

Wheres the dyno sheet?

[Dontbethatguy]

Originally Posted by ThomasMartin

Hey Guys Happy holidays to everyone im back from vacation so first reply for the new year.

Im currently running 98% at high altitutde and im not seeing any boost over 13.5 PSI. Shiv told me we cant damage the turbos as long as our boost stays below 15 PSI so what im asking is why do the cars at high altitiude run fine at 98% torque settings with normal pump gas. Shouldnt we be getting knocking codes?

You have a few things working for you at high altitude. For one, you can't make the same amount of boost with the same setting at high altitude. It's less atmospheric pressure. You have to turn the boost up to make the same boost level when you are at a higher altitude. A naturally-aspirated engine will make less power at higher altitude because of lower atmospheric pressure; there's less air at a higher altitude. This is why a car will feel so much faster at sea-level vs. at altitude. I consistently run .4 quicker at Texas Motorplex in my race car vs. my local track. There is a 3,000' altitude difference between the two tracks. Our turbos are small enough that they're most likely maxing out at higher altitudes, particularly with a factory exhaust. A stock exhaust can be a limiting factor for making additional boost on a turbo car. We saw it on our '05 twin turbo Corvette, but this was at 15 psi of boost making 907 RWHP through a stock exhaust. We dropped the cat-back, and it made 22 psi! I don't know that this is an issue for my car or not. I think the biggest issue is small turbos with a higher altitude. Besides not making the same boost, you also don't have the same octane requirements at a higher altitude. This applies more to naturally-aspirated engines, though.

I planned on turning the values down when it got warmer outside, but saying 100% is dangerous is a generalization. I can definitely see it being dangerous at sea-level, but I don't think it's a problem when I'm at altitude and won't make much more than 14 psi. It will take higher torque values at a higher altitude to make the same power and boost at sea-level. I definitely want to hear from Shiv since it's his tuning in the car, but if the car isn't seeing much more than 14 psi I don't see a problem. I'm also aware that it'll make less boost on our dyno. It doesn't have the load feature for turbo cars.

I'll try to get the graph up in the next day or so.

[leftcoastman]

Are you getting the data from the Procede software?

What are you showing at idle? If you are showing -1 psi at idle and then full boost shows 14psi, you are actually putting 15psi of stress on the turbos.

[DrewKo]

Does the car accelerate through the gears less favorably given your boost fluctuations? I have heard that V2 is very smooth.

[ThomasMartin]

Originally Posted by TrevorD

You have a few things working for you at high altitude. For one, you can't make the same amount of boost with the same setting at high altitude. It's less atmospheric pressure. You have to turn the boost up to make the same boost level when you are at a higher altitude. A naturally-aspirated engine will make less power at higher altitude because of lower atmospheric pressure; there's less air at a higher altitude. This is why a car will feel so much faster at sea-level vs. at altitude. I consistently run .4 quicker at Texas Motorplex in my race car vs. my local track. There is a 3,000' altitude difference between the two tracks. Our turbos are small enough that they're most likely maxing out at higher altitudes, particularly with a factory exhaust. A stock exhaust can be a limiting factor for making additional boost on a turbo car. We saw it on our '05 twin turbo Corvette, but this was at 15 psi of boost making 907 RWHP through a stock exhaust. We dropped the cat-back, and it made 22 psi! I don't know that this is an issue for my car or not. I think the biggest issue is small turbos with a higher altitude. Besides not making the same boost, you also don't have the same octane requirements at a higher altitude. This applies more to naturally-aspirated engines, though.

I planned on turning the values down when it got warmer outside, but saying 100% is dangerous is a generalization. I can definitely see it being dangerous at sea-level, but I don't think it's a problem when I'm at altitude and won't make much more than 14 psi. It will take higher torque values at a higher altitude to make the same power and boost at sea-level. I definitely want to hear from Shiv since it's his tuning in the car, but if the car isn't seeing much more than 14 psi I don't see a problem. I'm also aware that it'll make less boost on our dyno. It doesn't have the load feature for turbo cars.

I'll try to get the graph up in the next day or so.

Thanks so much Trevor its the first feedback we have gotten relating to cars at high altitude explaining how we should up torque settings compared to guys at sea level. I think cause 99% of Shiv's customers are at sea level the one or two of us at high altitude have struggled to get some sort of explination on how we should proceed increasing the levels without damaging the car and how the fuel oct will effect us. i can run 100% without having a problem with the fuel i would just like to know if there is any other damage done to the car if we runnig normal pump fuel but not getting any side effects?

Thanks again