3.3T Intake comparisons

[Volfy]

We went for a drive in both Stinger/G70 last night, with OBD2 bluetooth adapter plugged in and displaying via Torque Pro app on smartphone. Ambient temp was around 85F. As I expected, intake manifold air temp in a turbo engine behaves quite differently compared to naturally aspirated. Here are a few observations:

1. While vehicle speed certainly did have an influence on IAT, what made the most significant difference was ENGINE RPM. The higher the RPM, the lower the IAT. The effect is almost immediate following RPM rise/fall. This is no doubt related to the long induction path of the turbo-charged engine, as the intake air, after being sucked in through the inlet air filter, must traverse through a super hot turbo charger, the intercooler, and long runs of intake plumbing (which no doubt will be warm/hot inside the engine compartment. Residence Time of the intake air, while in the intake track, determines how much heat it soaks up before entering the intake manifold (where the IAT sensor is located). Higher RPM means higher intake air volume, which means higher intake air velocity, which means lower Residence Time. Ours are 2.0T with a single turbo. Logic would dictate that the 3.3TT is likely even more affected by residence time, with two turbo chargers and correspondingly more intake plumbing.

2. Even though we couldn't measure intake air temp at the air filter inlet (not yet anyway), we could see a pronounce difference between the bone stock Stinger (except a K&N filter in stock air box), and the G70 with Injen CAI with insulation added, which does two things:

a. Shield the intake track from engine compartment heat
b. Force the intake to draw air from either the stock air inlet port or the wheel well cavity, both of which are essentially at ambient temp.

Driven back to back, with the exact same OBD2 display, the Stinger recorded a typical low RPM (sub 1500RPM) IAT of around 114-116F. Changing gears at the same vehicle speed (~40mph) and raise the RPM to some 3000RPM, IAT dropped to 107-109F.

With the G70 at similar vehicle speed (~40mph), sub 1500RPM IAT was 109-111F. Raising the RPM (3000+) brought IAT down to 95-98F.

Clearly, the Cold Air Intake does make a remarkable difference. I only wish we had done this test prior to adding the radiant barrier insulation to the Injen intake system. We will get to do exactly that next month, since we have to remove the Injen CAI and put the stock intake back on for the AutoX event on July 10. After that, we will re-install the Injen CAI and have a chance to repeat the test again. I'm frankly not optimistic that the naked Injen system, even with the "heat shield" in place, will perform as well as being fully insulated/isolated. Air flow is lazy and will take the path of least resistance. With still so much open path to suck in underhood hot air, there is no incentive for the open cone filter to draw colder air from outside the engine compartment. While the bling factor is nice, I care much more about whether the Cold Air Intake actually does what its namesake promises. The potential is there. As delivered, however... meh. Sometimes, the modification requires, uh, modification.

 

[MichaelJohnson]

We went for a drive in both Stinger/G70 last night, with OBD2 bluetooth adapter plugged in and displaying via Torque Pro app on smartphone. Ambient temp was around 85F. As I expected, intake manifold air temp in a turbo engine behaves quite differently compared to naturally aspirated. Here are a few observations:

1. While vehicle speed certainly did have an influence on IAT, what made the most significant difference was ENGINE RPM. The higher the RPM, the lower the IAT. The effect is almost immediate following RPM rise/fall. This is no doubt related to the long induction path of the turbo-charged engine, as the intake air, after being sucked in through the inlet air filter, must traverse through a super hot turbo charger, the intercooler, and long runs of intake plumbing (which no doubt will be warm/hot inside the engine compartment. Residence Time of the intake air, while in the intake track, determines how much heat it soaks up before entering the intake manifold (where the IAT sensor is located). Higher RPM means higher intake air volume, which means higher intake air velocity, which means lower Residence Time. Ours are 2.0T with a single turbo. Logic would dictate that the 3.3TT is likely even more affected by residence time, with two turbo chargers and correspondingly more intake plumbing.

2. Even though we couldn't measure intake air temp at the air filter inlet (not yet anyway), we could see a pronounce difference between the bone stock Stinger (except a K&N filter in stock air box), and the G70 with Injen CAI with insulation added, which does two things:

a. Shield the intake track from engine compartment heat
b. Force the intake to draw air from either the stock air inlet port or the wheel well cavity, both of which are essentially at ambient temp.

Driven back to back, with the exact same OBD2 display, the Stinger recorded a typical low RPM (sub 1500RPM) IAT of around 114-116F. Changing gears at the same vehicle speed (~40mph) and raise the RPM to some 3000RPM, IAT dropped to 107-109F.

With the G70 at similar vehicle speed (~40mph), sub 1500RPM IAT was 109-111F. Raising the RPM (3000+) brought IAT down to 95-98F.

Clearly, the Cold Air Intake does make a remarkable difference. I only wish we had done this test prior to adding the radiant barrier insulation to the Injen intake system. We will get to do exactly that next month, since we have to remove the Injen CAI and put the stock intake back on for the AutoX event on July 10. After that, we will re-install the Injen CAI and have a chance to repeat the test again. I'm frankly not optimistic that the naked Injen system, even with the "heat shield" in place, will perform as well as being fully insulated/isolated. Air flow is lazy and will take the path of least resistance. With still so much open path to suck in underhood hot air, there is no incentive for the open cone filter to draw colder air from outside the engine compartment. While the bling factor is nice, I care much more about whether the Cold Air Intake actually does what its namesake promises. The potential is there. As delivered, however... meh. Sometimes, the modification requires, uh, modification.
View attachment 46305

Great information! I'm looking forward to your measurements without all of the reflective insulation. Surely that material is a net positive on your IATS. We'll know soon enough.

I didn't consider the engine RPM impact on the results. Fortunately, I did get a picture of the tach while recording exterior temperatures last night. Looks like my idle/cold start had engine RPM in the 800-900 range. The highway RPM was running around 1600.

I completely agree with you regarding the importance of "sourcing" air from outside of the engine compartment. Honestly, that was my highest priority when making a decision on which CAI to purchase. I know some of the other systems provide a good seal against the hood but I figured why chance it when there's a completely sealed housing that's available.

I'm going to start installing the AFE kit here in the next hour. I'll report back with some more measurements.

 

[Volfy]

Great information! I'm looking forward to your measurements without all of the reflective insulation. Surely that material is a net positive on your IATS. We'll know soon enough.

I didn't consider the engine RPM impact on the results. Fortunately, I did get a picture of the tach while recording exterior temperatures last night. Looks like my idle/cold start had engine RPM in the 800-900 range. The highway RPM was running around 1600.

I completely agree with you regarding the importance of "sourcing" air from outside of the engine compartment. Honestly, that was my highest priority when making a decision on which CAI to purchase. I know some of the other systems provide a good seal against the hood but I figured why chance it when there's a completely sealed housing that's available.

I'm going to start installing the AFE kit here in the next hour. I'll report back with some more measurements.

With the AFE kit... you chose wisely. I also like the K&N CAI system, for the same reason.

I shouldn't knock on the Injen system too much, especially at the (new to me) price I got it for. It is a mostly well-engineered piece of kit, and the included heat shield provides a solid 60% barrier structure that makes completing the full insulation/isolation very easy. I plan on changing out the blue Injen dry filter with a larger wet K&N cone filter. Even then I'd be out less $$ than the best price I can find for a new kit.

I knew this first test install was temporary, so we just slapped and taped on the radiant barrier haphazardly, just enough to be functionally to my liking. Next time we install it, I plan on doing a much cleaner/tidier job, with a removable lid, instead of taping the "air box" top shut.

Oh, forgot the mention although we did start recording logs with the Torque Pro app, we forgot to set up which parameters to record, so it only recorded a few basic PIDs by default. We'll play with that some to get it rigged up properly for the next round of testing.

 

[Volfy]

I know some of the other systems provide a good seal against the hood but I figured why chance it when there's a completely sealed housing that's available.

Excellent point. When we were doing the Injen install, my son noticed the G70's strut braces were actually kinda hot, despite the car not being driven overnight, so the engine was cold. We checked the Stinger, which has just being driven a hour ago, and the same strut braces were basically ambient temp. We scratched our heads for a while, before it dawned on us the only difference was the G70 had been sitting in directly sun. That hood was scorching hot! Despite Genesis having installed an OEM insulation pad on the underside, the hood was hot enough to heat up the strut braces.

Based on that, I'd say a CAI system that seal against the hood isn't such a hot idea (pun intended). That said, even though the Injen heat shield has a rubber gasket running along the top, the whole thing is under the strut brace and doesn't seal against anything. It serve no purpose other than maybe cosmetic.

That said, the one concern I have with drawing cold air through only the stock intake port on the front radiator support is a possible restriction that many folks have mentioned. I don't know enough to call it one way or the other, but I do like the way I've modified mine to have the option of drawing air from the front fender cavity also. A lot of car mfrs actually place their ambient temp sensor in the front fender cavity, precisely because that air space has possibly the best chance of being close to ambient temp.

 

[Slip_Angle]

Good info guys. I got a real quick snapshot yesterday and will collect more data in the coming days.


81F Ambient
106F after a minute or so driving at 50-60mph.
Max IAT was 147F while idling in traffic

I did not try to raise RPMs but will see the effect later today, however ambient is up today to 88F.

@Volfy - Interesting comparison between the G70 and Stinger. I wonder if the G70s larger grill opening also plays a part. Also looking forward to other comparisons between the two cars.

@MichaelJohnson - I'm really looking forward to seeing the AFE results.

 

[TwentyThreeG70]

Sorry if this is a dumb question. I am wanting to add an intake to my G70 but want to clarify something first. I see people reference that the car feels odd after they first install the intake, but they imply it just take a little time for the car to adapt to the new intake. Does the stock ECU adapt to the increased airflow over time? I just really want the intake for the sound difference but don't want to do something that will just cause headaches if I have to have it tuned. Thanks in advance!

Edit: Just for clarification, I only plan to do this one upgrade

 

[MichaelJohnson]

Sorry if this is a dumb question. I am wanting to add an intake to my G70 but want to clarify something first. I see people reference that the car feels odd after they first install the intake, but they imply it just take a little time for the car to adapt to the new intake. Does the stock ECU adapt to the increased airflow over time? I just really want the intake for the sound difference but don't want to do something that will just cause headaches if I have to have it tuned. Thanks in advance!

Edit: Just for clarification, I only plan to do this one upgrade

I'll have to get back to you on this. I just finished installation of the AFE kit.

 

[Volfy]

@Volfy - Interesting comparison between the G70 and Stinger. I wonder if the G70s larger grill opening also plays a part. Also looking forward to other comparisons between the two cars.

I don't doubt there are enough differences between the two corporate cousins to account for some of the differences I saw. There could also be some variations on the temp sensor calibration, even ones of the exact same part number. There is also the fact that my Stinger stock air intake does not have similar radiant barrier insulation, like we have on our G70. The OEM rubber intake runners don't conduct heat quite as efficiently as the Injen aluminum pipe, but soaked in underhood heat long enough, it still gets hot. In fact, while SCCA Solo rules on Street class specifically prohibits modification/removal of any part of the stock intake system (except the filter element), it does not say anything about adding insulation. We plan to exploit that to our advantage.

Anyhoo, best way to resolve that is to repeat the same test once we re-install the stock air intake in the G70, so we have data on the exact same car to compare.

Sorry if this is a dumb question. I am wanting to add an intake to my G70 but want to clarify something first. I see people reference that the car feels odd after they first install the intake, but they imply it just take a little time for the car to adapt to the new intake. Does the stock ECU adapt to the increased airflow over time? I just really want the intake for the sound difference but don't want to do something that will just cause headaches if I have to have it tuned. Thanks in advance!

Edit: Just for clarification, I only plan to do this one upgrade

I've also heard that same claim before, but I'm not convinced there is any merit to that. The ECU sees live datastream from the MAF and will adjust fuel input to match the mass air flow to drive towards target AFR. This is front end open-loop control based on stored maps. In addition to that, ECU will further adjust fuel trim based on Lambda (O2) sensor feedback. This is back end close-loop feedback control. All this occurs regardless of what intake system you have on your car. The ECU simply has no way of "seeing" what you have upstream of the turbo charger... and it doesn't need to.

Will the ECU readjust its fuel control if your new intake is freer flowing? Of course it will. However, all the adjustments happen dynamically, without need for user input. Some systems do require adaptation or relearning if you do a hard reset on emissions control parameters or change out certain critical parts, like MAF. Just changing intake... I doubt it. Even if the ECU does need to go thru its adaptation routine, there isn't anything you need to worry about or pay for an ECU retune.

In short, I wouldn't worry about it.

 

[MichaelJohnson]

I'm out driving right now and I can confirm the car is limiting power. Just remembered that I had my JB4 on map 2. I put it back to 0 (disabled). Now I'm going to run the car for a bit. Hopefully that will get thing straightened out.

 

[MichaelJohnson]

So I drove the car for nearly 2 hours and it is limiting torque to just over 200. It was a good mix of city, highway, and curvy country roads. I checked all of the connections while I was out and right after I got home. Nothing was loose. Also, no codes ever popped up.

Anyway, I have the battery disconnected for the evening. I'll reconnect it tomorrow morning after finishing the install of my JB4 EWG wires. I installed the connectors but I haven't connected them to the JB4 yet. It's possible this has something to do with the car limiting torque. However, I would think a code would pop up if that were the case.

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[Slip_Angle]

So I drove the car for nearly 2 hours and it is limiting torque to just over 200. It was a good mix of city, highway, and curvy country roads. I checked all of the connections while I was out and right after I got home. Nothing was loose. Also, no codes ever popped up.

Anyway, I have the battery disconnected for the evening. I'll reconnect it tomorrow morning after finishing the install of my JB4 EWG wires. I installed the connectors but I haven't connected them to the JB4 yet. It's possible this has something to do with the car limiting torque. However, I would think a code would pop up if that were the case.

What do you mean it's limiting torque? I'm not sure what the context is you are talking about. Good to hear no codes and things are running well. Do you have pics?

I noticed today that boost hit 15.5psi on the way home as seen by Torque Pro. My car is stock other than the VT snorkels and a TCU with the torque limits removed. I believe stock is up to 14psi on the AWD, so that's pretty interesting. I wonder if it's the VT snorkels or the TCU allowing more torque or both...

 

[exbimmer]

Do any of these mods violate the warranty of the car?

 

[MichaelJohnson]

What do you mean it's limiting torque? I'm not sure what the context is you are talking about. Good to hear no codes and things are running well. Do you have pics?

I noticed today that boost hit 15.5psi on the way home as seen by Torque Pro. My car is stock other than the VT snorkels and a TCU with the torque limits removed. I believe stock is up to 14psi on the AWD, so that's pretty interesting. I wonder if it's the VT snorkels or the TCU allowing more torque or both...

By limiting torque I mean that under any driving conditions the torque display in the gauge cluster would peak just over 200. I also ran several WOT pulls from 20 mph and dead stop. The car was limiting output somehow.

Oddly enough, it would still push each gear close to redline and then shift. That part seemed normal. Just didn't have the same power output. I should have run a couple logs on the JB4 but I forgot. The car was still building plenty of boost from what I could see on the gauge cluster.

I'll head out to the garage here in a bit and finish wiring in the EWG connectors. Then I'll take the car out and report back. It's had the battery unplugged all night.

 

[Slip_Angle]

By limiting torque I mean that under any driving conditions the torque display in the gauge cluster would peak just over 200. I also ran several WOT pulls from 20 mph and dead stop. The car was limiting output somehow.

Oddly enough, it would still push each gear close to redline and then shift. That part seemed normal. Just didn't have the same power output. I should have run a couple logs on the JB4 but I forgot. The car was still building plenty of boost from what I could see on the gauge cluster.

I'll head out to the garage here in a bit and finish wiring in the EWG connectors. Then I'll take the car out and report back. It's had the battery unplugged all night.

The car normally limits torque in 1st and 2nd gear to protect the drivetrain. I found when I had a JB4 installed that the more boost I ran, the more the car dialed things back until 3rd gear and then the power was allowed. This is a bit anecdotal because I didn't log it or dig deep but my 0-60 times didn't consistently improve with JB4 when boost was increased. Once I got a TCU tune, everything changed. Try rolling into the throttle and shifting really early (4K) just to see what torque looks like on the gauge... or try a 3rd gear full send and you should see a difference.

 

[MichaelJohnson]

The car normally limits torque in 1st and 2nd gear to protect the drivetrain. I found when I had a JB4 installed that the more boost I ran, the more the car dialed things back until 3rd gear and then the power was allowed. This is a bit anecdotal because I didn't log it or dig deep but my 0-60 times didn't consistently improve with JB4 when boost was increased. Once I got a TCU tune, everything changed. Try rolling into the throttle and shifting really early (4K) just to see what torque looks like on the gauge... or try a 3rd gear full send and you should see a difference.

I appreciate your feedback man! The car was limiting power regardless of gear and independent of the JB4. Power was limited in the city, on curvy roads, and on Interstate 75. I really tried to cover as many driving conditions as possible.

I just pulled over at a gas station after taking the car for a spin in the Cherokee National Forest. I left the JB4 off and didn't start pushing the car until I had driven it for 46 minutes. I took it down an extremely curvy road that lasts for about 20 minutes. The car was in Sport + for the test and I used the paddle shifters. I pushed it a bit and she delivered . I've definitely pushed the car more on this road but decided to take it easy so I could confirm everything was back to normal. Once I got back to the highway I turned the JB4 to map 2 and let her rip. She didn't disappoint.

 

[MichaelJohnson]

@Slip_Angle Do you have an ECU and TCU tune?

 

[Slip_Angle]

@Slip_Angle Do you have an ECU and TCU tune?

Yes, I have both but at the moment I just have the TCU tune installed.

 

[Volfy]

@MichaelJohnson sounds to me like your car wasn't limiting torque prior to the CAI install. Is this correct?

I cannot imagine what about the AFE kit that would trigger the ECU to limit torque.

 

[MichaelJohnson]

@MichaelJohnson sounds to me like your car wasn't limiting torque prior to the CAI install. Is this correct?

I cannot imagine what about the AFE kit that would trigger the ECU to limit torque.

You are correct. There were no issues before the install of the AFE kit. It could have had something to do with with the fact that I installed the EWG connectors at the same time as the intake kit. Each waste gate had to be unplugged. I usually disconnect the battery before I install mods on any vehicle but I didn't this time. I knew better...

Here's a picture with the intakes installed.

 

[Volfy]

I see. That does sound more likely to be the culprit.

In any case, it's always best to do one mod at a time, even if it is tempting to get them all done at once.