NATOR CO GTX2867

[Mortose]

Ok, so with all the hype about the GTX2867 that has recently popped up, i went ahead and grabbed up one of these little guys. And when i say little, well here ya go:



So, the install went just like any other turbo install. so i'm not going to sit here and describe that for everybody. Though, we did run into some issues, so incase anyone ever searches and has the same issues: Upon initial start up, it would hold idle well, and a 14.7 AFR, then about 10-15 sec's later, it would tank the AFR down to 8.X and lose vacuum. We checked all the couplers and all the joints. Re-attached everything making sure its snug, and tested again with the same results. Fast forward to this morning. @RLam; came by to help with some MAF cleaner, so we sprayed off the MAF, and tested the car. AFR's stayed in the 12.X range, but still wanted to die. Out of frustration we checked all the couplers, cleaned the O2 sensor, pulled and cleaned the MAP sensor and uninstalled and reinstalled the AP. This seemed to fix the issue. Car ran like crap, but held idle at 13.X AFR. after a quick spin and letting it sit, all the numbers leveled out to normal.

Took some logs today on my base map from @Lex; and i've attached those for peoples viewing pleasure.

I will keep this thread going with my tuning results with 91 and E85.

Edit: So with this turbo gaining a little traction, i figured i would mention something i noticed. I went with the HTP full 3" alluminum intake. I love it. Reduced risk of leaks, and from what i saw, the only intake with a 3" inlet size. One thing that i would sudgest is that you get some sort of an aftermarket battery box. I had to remove the plastic cover for my ECU, and its still tighter than a virgin in my engine bay.

[aggierandy]

In for results

RapaTapTap

[Stealth01]

I wonder if cleaning my O2 sensor or MAP sensor would help my lean issues.......

Congrats, bud.

[RLam]

Originally Posted by Stealth01 I wonder if cleaning my O2 sensor or MAP sensor would help my lean issues....... Congrats, bud.

It's worth a shot. It's easy and cheap to try. His MAF sensor was caked in crap. It improved his idle, although the problem still remained.

[Mortose]

So, an update, after driving it around for a few days, i'm on my 3rd revision and ~22lbs.

My exhaust is noticeably louder, and the turbo sounds like a damn supercharger! but i do have to say that i love the sound.

I'll post up some VD numbers after a couple more revisions.

[Dimenus]

Updates? .

I want this turbo.

[Mortose]

No major updates. Lex has been out of town over the weekend. Right now he is working on boost. Once we get into timing, I'll post VD numbers.


Give it a little tappy, a tap tap tap-a-roo

[Mortose]

Alright, so a little update. We have reached, what lex feels, is a solid 91 tune. With ambient temps in the 80's and IAT in the 90's to 100's, lex feels that we are about as far as we can go. I'm happy with this, as it will be primarily a road trip map for the car. I will post the logs i take tomorrow. Once those are done, then we are starting on my E85 mix tune.

[Yatta]

The poor running resolved by the AP uninstall/reinstall... part of doing that is a complete reset of the ECU ? was the battery disconnected while replacing the turbo? the st/lt fuel requirements would be affected by the difference in restriction... just a thought. how is spool compared to the stock?

[Mortose]

yes, the unistall/reinstall is to "start over" as it were on the ECU. with my K04 tune, something we ran into that was fixed by the same process was that my AFR's weren't getting to the commanded levels.

Yes, the battery was disconnected, as i was standing on the motor mount durring install. lol

The spool is a little slower than the K04, about 4-600 RPM later, but still much faster than a 3071.

So far, if your not looking to make all the power under the sun, but still want a turbo upgrade, this is an awesome turbo.

thanks again to @EdgeAutosport.com; for hooking me up with this little beast!

[Mortose]

Ok, so here are the logs for everyone to see!!!

and more to come, as i just put in my E85 mix, and will keep this updated.

also, please remember that i'm at 6400 ASL. lol

[Dimenus]

Man, 6400 ASL sucks . That makes me sad. I'm still considering this turbo but I'm at 315-320/365 here close to sea level on the little snail.

[Mortose]

Originally Posted by Dimenus Man, 6400 ASL sucks . That makes me sad. I'm still considering this turbo but I'm at 315-320/365 here close to sea level on the little snail.

That's why they invented correction factor to make us up here feel better about ourselves. Little prospective, I was at 360/426 corrected with e mix here, an corrected now, I'm over 370. So that kinda puts a better spin on it. Lol


Give it a little tappy, a tap tap tap-a-roo

[LumberJack]

Looks good man, in for results and the big numbers

[aggierandy]

Originally Posted by Mortose That's why they invented correction factor to make us up here feel better about ourselves. Little prospective, I was at 360/426 corrected with e mix here, an corrected now, I'm over 370. So that kinda puts a better spin on it. Lol Give it a little tappy, a tap tap tap-a-roo

Forgive my noob question here but do dyno correction factors differ between naturally aspirated and forced induction cars?

[DVM17]

Originally Posted by aggierandy Forgive my noob question here but do dyno correction factors differ between naturally aspirated and forced induction cars?

Forced induction loses less power at higher altitudes. Basically, because the air is less dense the higher you go, the turbo cars can suck in more air than N/A cars thus cancelling the loss of power more than N/A cars would. Turbos were actually invented, if I remember correctly, for airplanes not to lose as much power at high altitudes. So esentially, it was made for higher power above sea level.

[Dimenus]

That still seems like a bit of an overcompensation to me. 360/426 on stock turbo is insane.

[DVM17]

Originally Posted by Dimenus That still seems like a bit of an overcompensation to me. 360/426 on stock turbo is insane.

I agree completely. A guy in our group dyno'ed on a dynojet (reads high) at 370wtq with E33 and full bolt ons and a very aggressive (unsafe) tune

[Dimenus]

Originally Posted by DVM17 I agree completely. A guy in our group dyno'ed on a dynojet (reads high) at 370wtq with E33 and full bolt ons and a very aggressive (unsafe) tune

That's about where I'm at with my stratified tune w/ bolts on other than manis (VD cf 1.01). I should be able to jump on the dyno in about two weeks to verify.

Lex did say that I have about the ideal setup for stock turbo though.

[aggierandy]

Originally Posted by DVM17 Forced induction loses less power at higher altitudes. Basically, because the air is less dense the higher you go, the turbo cars can suck in more air than N/A cars thus cancelling the loss of power more than N/A cars would. Turbos were actually invented, if I remember correctly, for airplanes not to lose as much power at high altitudes. So esentially, it was made for higher power above sea level.

Thanks for your response. I am aware of this and that was the reasoning behind my question.

Is the same correction factor applied to an NA car as to an FI car when adjusting for altitude?

RapaTapTap

[DVM17]

Originally Posted by Dimenus That's about where I'm at with my stratified tune w/ bolts on other than manis (VD cf 1.01). I should be able to jump on the dyno in about two weeks to verify. Lex did say that I have about the ideal setup for stock turbo though.

yea, he's actually tuning with lex now, because he needs some safety. lol it's a '13 ms3

Originally Posted by aggierandy Thanks for your response. I am aware of this and that was the reasoning behind my question. Is the same correction factor applied to an NA car as to an FI car when adjusting for altitude? RapaTapTap

I wouldn't think so. It wouldn't make sense for the factor to be the same when N/A loses so much more power.

[aggierandy]

Originally Posted by DVM17 yea, he's actually tuning with lex now, because he needs some safety. lol it's a '13 ms3 I wouldn't think so. It wouldn't make sense for the factor to be the same when N/A loses so much more power.

So if not, how is the correction factor for FI cars selected. Peak boost? Average boost?

Either way OP, drive that thing down here to sea level and let us know where you are really at!!!

[DVM17]

Originally Posted by aggierandy So if not, how is the correction factor for FI cars selected. Peak boost? Average boost? Either way OP, drive that thing down here to see level and let us know where you are really at!!!

In my mind, it shouldn't matter what amount of boost your running (since the dyno just has to convert the equation hp= (2*pi*torque*rpm)/ 33000 ) I.E. the more boost you run, the more power you'll have (obviously) and the correction factor also has to do with assuming the vehicle is 85% mechanically efficient. There's a lot that goes on in the computer to get a correction factor.

Tl;dr: correction factor should be the same as the N/A's equation for correction, but will have different values determining exactly how much more efficient turbo vehicles are when compared to N/A vehicles at a given altitude.

Sorry, hard to explain in my mind.

Here's the equation that I typed up for the N/A.

Cf= 1.176((990/Pd)*(Tc+273/298)^0.5) - 0.176

Obviously Cf = Correction Factor. lol
And Pd = The pressure of the dry air, in mb
And Tc = Ambient temperature, in degrees C

[aggierandy]

Originally Posted by DVM17 In my mind, it shouldn't matter what amount of boost your running (since the dyno just has to convert the equation hp= (2*pi*torque*rpm)/ 33000 ) I.E. the more boost you run, the more power you'll have (obviously) and the correction factor also has to do with assuming the vehicle is 85% mechanically efficient. There's a lot that goes on in the computer to get a correction factor. Tl;dr: correction factor should be the same as the N/A's equation for correction, but will have different values determining exactly how much more efficient turbo vehicles are when compared to N/A vehicles at a given altitude. Sorry, hard to explain in my mind.

Nah, its not that complicated.

Equations: Dyno Correction Factor and Relative Horsepower

I looked up the equation. Only two variables, temperature and pressure. Same CF for Na and FI. That leads me to believe that CF for FI cars are hokey and likely overcompensate.

[DVM17]

Originally Posted by aggierandy Nah, its not that complicated. Equations: Dyno Correction Factor and Relative Horsepower I looked up the equation. Only two variables, temperature and pressure. Same CF for Na and FI. That leads me to believe that CF for FI cars are hokey and likely overcompensate.

Hmmm, they specify it's only for N/A vehicles though....

[DVM17]

found this on another forum.

N/A = correction factor Supercharged = correction factor * .9 Turbocharged = correction factor * .5

and right after that

N/A = correction factor SC = correction factor Turbo = no correction, provided EBC and turbo has enough capacity/headroom to compensate

From what I have seen, both supercharged and normally aspirated cars seem to follow the correction factor pretty well. Turbos are a bit off, but it depends on the type of turbo that is being run. It depends on at what range the turbo is operating in its efficiency map. A turbo that is sized on the small side for sea level use, will have a different percent drop in power as you go up in altitude vs. a slightly oversized one. Specifically, a turbo is free to spin to a higher turbine rpm vs. engine rpm to try and maintain boost as one goes up in altitude. Superchargers on the other hand have a fixed belt ratio.

IDK. I'm done looking at all these equations lol

[aggierandy]

Originally Posted by DVM17 found this on another forum.

Interesting but probably not that accurate. The correction factor would be dependant on the efficiency of the turbo at specific rpms and air densities. Unless you plugged the compressor map into the computer and it used a specific correction factor at each point, the cf is probably not that accurate.

RapaTapTap

[DVM17]

Yea, so it seems like the consensus is that the "corrected numbers" are way higher than they should be.

Someone needs to take 10 or so FI cars to a dyno at sea level, then to one at 6000' asl and see the average percentage difference and then factor the loss for each 100 feet in or something.

Same test with different turbo setups as well. I can see why people haven't done it yet. (that I know of) lol

[aggierandy]

Originally Posted by DVM17 Yea, so it seems like the consensus is that the "corrected numbers" are way higher than they should be. Someone needs to take 10 or so FI cars to a dyno at sea level, then to one at 6000' asl and see the average percentage difference and then factor the loss for each 100 feet in or something. Same test with different turbo setups as well. I can see why people haven't done it yet. (that I know of) lol

Well, if there was a company with the money to do that it would be AMS. Here is their opinion on the matter:

How Dynamometers work, correction factors and dyno types - Engine - GT-R Life

[DVM17]

Originally Posted by aggierandy Well, if there was a company with the money to do that it would be AMS. Here is their opinion on the matter: How Dynamometers work, correction factors and dyno types - Engine - GT-R Life

interesting. So what I said was on the right track. The numbers should be lower than I've seen if correctly corrected. Good write up. No more debating now. lol

[Mortose]

all i have to say to all of that:

STOP RUINING MY NUMBERS!!!!

I completely agree that the CF for us here at 6400 ASL is a little overkill for a FI car. But at the same time, the uncorrected numbers a SO disheartening!!!

I can tell folks, i moved from the panhandle of FL to CO, so i went from 0 ASL to 6400, and i could honestly tell that i lost 30-60 hp. my car felt slow as shit when i got here, like i was hauling around an extra 800 lbs.

[aggierandy]

Originally Posted by Mortose all i have to say to all of that: STOP RUINING MY NUMBERS!!!! I completely agree that the CF for us here at 6400 ASL is a little overkill for a FI car. But at the same time, the uncorrected numbers a SO disheartening!!! I can tell folks, i moved from the panhandle of FL to CO, so i went from 0 ASL to 6400, and i could honestly tell that i lost 30-60 hp. my car felt slow as shit when i got here, like i was hauling around an extra 800 lbs.

Lol, sorry to shit on your parade there. Let me play with the numbers later.

RapaTapTap

[Mortose]

It's all good. Almost all the cars that we hang out with are all FI, so it's a decent comparison across the board for us.

I would definitely like to see what this thing feels like at sea level though. iirc @atvfreek; is at sea level, so he would be able to give good insite.

But back to the turbo, so far I love it. It's great for DDing every day. Spools quick, and power just holds. All i have to do is stage myself around 3200 rpm, and no break boosting needed. Not to mention that I love the sound of it, it just screams when your in boost.


Give it a little tappy, a tap tap tap-a-roo

[aggierandy]

Originally Posted by Mortose It's all good. Almost all the cars that we hang out with are all FI, so it's a decent comparison across the board for us. I would definitely like to see what this thing feels like at sea level though. iirc @atvfreek; is at sea level, so he would be able to give good insite. But back to the turbo, so far I love it. It's great for DDing every day. Spools quick, and power just holds. All i have to do is stage myself around 3200 rpm, and no break boosting needed. Not to mention that I love the sound of it, it just screams when your in boost. Give it a little tappy, a tap tap tap-a-roo

Did some creative (and probably incorrect) math and came up with a correction factor of 1.06881. This would put you at 316/341. Its logical in it is between your corrected and uncorrected (and its closer to the uncorrected) but it is impossible to say how accurate it really is.


If anyone cares, I simply took the total pressure to the motor at elevation divided it by the total pressure at sea level to get a percent reduction in total pressure. (91.4%) multiplied that pressure by sea level atmospheric pressure and used this pressure to determine the SAE correction factor (cf=1.06881). I also used your intake temp as ambient (17.75C).

It doesn't really mean anything because at sea level the turbo will behave differently due to the denser air.

[atvfreek]

Originally Posted by Mortose It's all good. Almost all the cars that we hang out with are all FI, so it's a decent comparison across the board for us. I would definitely like to see what this thing feels like at sea level though. iirc @atvfreek; is at sea level, so he would be able to give good insite. But back to the turbo, so far I love it. It's great for DDing every day. Spools quick, and power just holds. All i have to do is stage myself around 3200 rpm, and no break boosting needed. Not to mention that I love the sound of it, it just screams when your in boost. Give it a little tappy, a tap tap tap-a-roo

A boosted car definitely doesn't lose as much hp as an N/A car, but there are obviously still loses.

@snailD; is at elevation and ran a 13.2@113ish and he is on a similar tune as me, I ran a 12.9@117. We both had a similar 60ft, so in a race, and using track numbers rather than dyno numbers, that is the difference at elevation in a FI car

[Mortose]

Originally Posted by aggierandy Did some creative (and probably incorrect) math and came up with a correction factor of 1.06881. This would put you at 316/341. Its logical in it is between your corrected and uncorrected (and its closer to the uncorrected) but it is impossible to say how accurate it really is. If anyone cares, I simply took the total pressure to the motor at elevation divided it by the total pressure at sea level to get a percent reduction in total pressure. (91.4%) multiplied that pressure by sea level atmospheric pressure and used this pressure to determine the SAE correction factor (cf=1.06881). I also used your intake temp as ambient (17.75C). It doesn't really mean anything because at sea level the turbo will behave differently due to the denser air.

I would judge that your math leans to the conservative side, but I'm not about to try and do the math.

Lol.

But I would imagine that, like you said, the car would react very different at sea level, and 93 oct fuel.


Give it a little tappy, a tap tap tap-a-roo

[aggierandy]

Originally Posted by aggierandy Did some creative (and probably incorrect) math and came up with a correction factor of 1.06881. This would put you at 316/341. Its logical in it is between your corrected and uncorrected (and its closer to the uncorrected) but it is impossible to say how accurate it really is. If anyone cares, I simply took the total pressure to the motor at elevation divided it by the total pressure at sea level to get a percent reduction in total pressure. (91.4%) multiplied that pressure by sea level atmospheric pressure and used this pressure to determine the SAE correction factor (cf=1.06881). I also used your intake temp as ambient (17.75C). It doesn't really mean anything because at sea level the turbo will behave differently due to the denser air.

Checked my math using AMS's sample problem (I don't know if they made up the numbers for their example or if they are real) and it gave me a correction factor of 1.087 or 98.9 hp corrected. Close but a little conservative. I think we all agree there is an impact and there are a lot of variables to take into account.

I don't think I could own an NA car at anything higher than about 2000 ASL. LOL

[Dimenus]

This little turbo looks really appetizing to me. Can I ask how much it costs to go from k04 to this? If I could do it all for around 2k I might just bite the bullet.

[Mortose]

Originally Posted by Dimenus This little turbo looks really appetizing to me. Can I ask how much it costs to go from k04 to this? If I could do it all for around 2k I might just bite the bullet.

I would talk to edge about it. I'm on my phone, so I don't know what mods you have right now, but you need an ebcs, intake, turbo, 3bar and harness, and other supporting mods.


Give it a little tappy, a tap tap tap-a-roo

[Dimenus]

How's the tune shaping up?