• Sign Up! To view all forums and unlock additional cool features

    Welcome to the #1 Dodge, Jeep and RAM Forum dedicated to FCA owners and enthusiasts. Register for an account, it's free and it's easy, so don't hesitate to join the SRT Forum today!


"Project Demons Breath"

PaVaSteeler

Mole
Founding Member
Member ID
#1001
Messages
1,081
Reactions
1,268
Likes
162
State
VA
Country
United States
I have a App on my IPhone called Density Alt+. I think it was $1.99 to purchase. My son is a professional helicopter pilot flying search and rescue in the Sierras and he is using it. It shows GPS altitude, Barometric pressure, Altimeter setting and Temp as well as the DA. I check it all the time as I travel and it is right on as far as GPS altitude goes, so it definitely knows where it is. Takes seconds to get a read out. It’s showing DA is 5156’ at my house right now. Alt is 3231 ft and OAT is 80 degrees.
FYI - while researching this App, it appears it uses only a dry air formula to calculate DA. In the course of my ongoing research to build an Excel spreadsheet compatible with an iPad, my research into DA calculations for drag racing repeatedly comes back to the necessity of including the "water content" formulas for a more accurate DA calculation, especially when tuning is/may be involved.

The Kestrel meters use the aviation-oriented formulas, many/most based on the ISA standard (International Standard Atmosphere). This standard, as well as the standards used by the aerospace and automotive industry focus on the air density, while the Motorsports Standard focuses on the oxygen density, to arrive at a DA figure.

My $0.02
 


Last edited:

Speedy!

Infomercial Producer
Staff Team
Founding Member
U.S. Marine Veteran
9 Second Best E/T
HFCOTM & HFCOTY
Member ID
#1070
Messages
6,704
Reactions
17,224
Likes
402
City
Interwebs
State
TN
Country
United States
Vehicle
Demon 170
Bummer it's only for Apple as well.....I'm allergic to Apples.
 


OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #163
Bummer it's only for Apple as well.....I'm allergic to Apples.
Lol me too!

Sent from my BBF100-2 using Tapatalk
 


coolblue

1000 Posts Club
Founding Member
Donating Member
Member ID
#1172
Messages
1,577
Reactions
2,696
Likes
162
City
Long Island
State
NY
Country
United States
Vehicle
2019 Redeye
Ok I'm just going to come out and say it ...... While running down the drag strip I really did enjoy watching the demons shrink away in my mirrors . Lol
Yes I said that
Shhhh. No one tell DEMON1. :D
Sent from my BBF100-2 using Tapatalk
 


hellno

3000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#1308
Messages
3,336
Reactions
5,829
Likes
302
City
memphis
State
TN
Country
United States
Vehicle
2016 challenger hellcat
I have an apple phone ,yall know we have a thread for trash talking :ROFLMAO:
I have an auto density app ,it was free to download and I checked it and its accurate with in 5000 DA
 


hellno

3000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#1308
Messages
3,336
Reactions
5,829
Likes
302
City
memphis
State
TN
Country
United States
Vehicle
2016 challenger hellcat
1129A7B1-D573-4FCE-8E87-12177298527E.png
 


Blkout

500 Posts Club
Founding Member
Donating Member
Member ID
#1095
Messages
852
Reactions
1,383
Likes
132
City
Warner Robins
State
GA
Country
United States
Vehicle
2016 Challenger Hellcat
I tested 3 different intakes with 4 passes each . I tried to give equal cool downs/ hot laps and with out a doubt the LMI netted me my best MPH and ET . The JLT was pretty close and the stock one was definitely behind . I'm going to over all my logs tomorrow and the next few days . It's was also hot and humid here today ( 88-96F) all day with Crappy DA ( 2500-3300 ) . The results I got are for MY CAR today . It is not written in stone for everyone . Results will very .


Stock
Best pass 10.1@ 137
Worst pass 10.4@ 135 (hot lap with tire spin)
2 other passes 10.3X@ 136

JLT
Best pass 10.0@141.7 (tire spin)
Worst pass 10.4@ 137 (hot lap with tire spin)
2 other passes 10.1X@ 139

LMI
Best pass 9.82@142.5
Worst pass 10.3@137 (2nd hot lap right after stock box test and tire spin)
2 other pass 9.9X@140

I then left the LMI on for the rest of the day . And got more 9.8X@ 140+ mph .

I got 15 passes total today

Sent from my BBF100-2 using Tapatalk
Did the stock box have a stock filter or K&N?

I have little doubt an aftermarket free flowing intake will make a little more power on a modified cat, but doubt there's any to be gained on a stock cat just because the engineers have already designed the stock box to flow enough air for the stock engine requirements.

Is it also possible that the LMI made more power since it was tested last and most likely when track conditions were cooler or were all of these tests done in the same ambient temp during the middle of the day?
 


OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #168
Did the stock box have a stock filter or K&N?

I have little doubt an aftermarket free flowing intake will make a little more power on a modified cat, but doubt there's any to be gained on a stock cat just because the engineers have already designed the stock box to flow enough air for the stock engine requirements.
I ran no filter ( on the street I use a K&N drop in) . I agree with you and have said the same thing . Not much gain on a stock to mild stock . But there will be a point where the engine will need more volume . Every car will have a different "point" if any .

Sent from my BBF100-2 using Tapatalk
 


Blkout

500 Posts Club
Founding Member
Donating Member
Member ID
#1095
Messages
852
Reactions
1,383
Likes
132
City
Warner Robins
State
GA
Country
United States
Vehicle
2016 Challenger Hellcat
I ran no filter ( on the street I use a K&N drop in) . I agree with you and have said the same thing . Not much gain on a stock to mild stock . But there will be a point where the engine will need more volume . Every car will have a different "point" if any .

Sent from my BBF100-2 using Tapatalk
My car made 871whp using an LMI so I don't doubt that I'm at a point that would benefit from it. Just looking at your results though seems like a HUGE variance from the stock box which is a little hard to imagine so I'm looking at any other variables that made have made a difference such as stock filter or ambient temps.

I'm actually about to swap my LMI for an AFE Stage 2 Pro 5R
 


hellno

3000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#1308
Messages
3,336
Reactions
5,829
Likes
302
City
memphis
State
TN
Country
United States
Vehicle
2016 challenger hellcat
I ran no filter ( on the street I use a K&N drop in) . I agree with you and have said the same thing . Not much gain on a stock to mild stock . But there will be a point where the engine will need more volume . Every car will have a different "point" if any .
According to the logs I looked at the jlt cai was definitely better
I didn’t see the stock airbox logs
Sent from my BBF100-2 using Tapatalk
 


hellno

3000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#1308
Messages
3,336
Reactions
5,829
Likes
302
City
memphis
State
TN
Country
United States
Vehicle
2016 challenger hellcat
The stock airbox is very good but the redeye and the demon airbox is different , I assume because of the bigger blower
 


coolblue

1000 Posts Club
Founding Member
Donating Member
Member ID
#1172
Messages
1,577
Reactions
2,696
Likes
162
City
Long Island
State
NY
Country
United States
Vehicle
2019 Redeye
The stock airbox is very good but the redeye and the demon airbox is different , I assume because of the bigger blower
And cam. You know I went on Kenne Bell's website some time ago to compare his stats to a Magnuson setup (which is what I have) They said in ALL their tests it was shown you just cant have enough air with a blown motor (Any blown motor) the least restriction the better. That's why they made the mammoth 148mm TBI.
 


Last edited:
OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #173
My car made 871whp using an LMI so I don't doubt that I'm at a point that would benefit from it. Just looking at your results though seems like a HUGE variance from the stock box which is a little hard to imagine so I'm looking at any other variables that made have made a difference such as stock filter or ambient temps.

I'm actually about to swap my LMI for an AFE Stage 2 Pro 5R
The ambient temps that day started off at 88f plus humidity and peaked at 96F plus humidity. The Da started off around 2500 and peaked at 3300. The day was gross. I ran 4 passes on each intake . I tried to keep each pass as equal as possible. ( a big cool down then a hot lap then 2 20 min cool downs) .

Sent from my BBF100-2 using Tapatalk
 


OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #174
OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #175
My car made 871whp using an LMI so I don't doubt that I'm at a point that would benefit from it. Just looking at your results though seems like a HUGE variance from the stock box which is a little hard to imagine so I'm looking at any other variables that made have made a difference such as stock filter or ambient temps.

I'm actually about to swap my LMI for an AFE Stage 2 Pro 5R
Let me know how that intake works out .
I'm just as surprised as anyone with the results . But I was there with 4 other members who actually helped with the intake swapping . Blkout I have no reason to lie or fudge the results as I have nothing to gain . I'm actually going to try the test again in better weather . The biggest thing was the stock air box got heat soaked fast and took for ever to cool down . Where as the other 2 took longer to get hot and cooled down much quicker. Heck in one of my logs you can actually see the "inlet air temperature " dropping as I'm going down the track .

Sent from my BBF100-2 using Tapatalk
 


OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #176
I have a demon supercharger(over driven 10%), demon cam, fastman throttle body. These will all lead to higher air flow requirements. Plus the 2.7L supercharger will run cooler IAT;s VS a over spun 2.4L at the same boost pressure.

Sent from my BBF100-2 using Tapatalk
 


Blkout

500 Posts Club
Founding Member
Donating Member
Member ID
#1095
Messages
852
Reactions
1,383
Likes
132
City
Warner Robins
State
GA
Country
United States
Vehicle
2016 Challenger Hellcat
Let me know how that intake works out .
I'm just as surprised as anyone with the results . But I was there with 4 other members who actually helped with the intake swapping . Blkout I have no reason to lie or fudge the results as I have nothing to gain . I'm actually going to try the test again in better weather . The biggest thing was the stock air box got heat soaked fast and took for ever to cool down . Where as the other 2 took longer to get hot and cooled down much quicker. Heck in one of my logs you can actually see the "inlet air temperature " dropping as I'm going down the track .

Sent from my BBF100-2 using Tapatalk
I'm not implying your lying at all, the trap speed delta just seems hard to swallow. Only looking for other variables that might have contributed. What you say about the stock box heat soaking is 100% correct and I've told people this over and over at the other forum. Many people swear that because the LMI has higher IAT temps when idling in traffic that the stock box is better but I've said time and again, the LMI's IAT's also go down much more rapidly once the car starts moving again because the stock box has so much plastic to cool down.

IAT's are less of an issue for me with the FI Interchiller but I do like some blower whine and don't want a restrictive intake at my power level. I've decided to try the AFE because I like the heat shield but its not a complete box like the JLT which just seems like another plastic box to cool down like the factory box. The AFE seems like the best of both worlds, similar to the LMI in that there's no plastic box to cool, but it does have a shield to block some engine heat unlike the LMI. We'll see but honestly I'm not expecting radically different results from the LMI.
 


hellno

3000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#1308
Messages
3,336
Reactions
5,829
Likes
302
City
memphis
State
TN
Country
United States
Vehicle
2016 challenger hellcat
Actually both of the JLT logs the iat get cooler throughout the pass
 


hellno

3000 Posts Club
8 Second Best E/T
HFCOTM
Member ID
#1308
Messages
3,336
Reactions
5,829
Likes
302
City
memphis
State
TN
Country
United States
Vehicle
2016 challenger hellcat
On my logs the iat only gets hotter down the track but I didn’t log when the car was stock
 


OP
Hpindy

Hpindy

4000 Posts Club
Founding Member
9 Second Best E/T
HFCOTM
Member ID
#974
Messages
4,875
Reactions
11,023
Likes
302
City
Jackson's Point
State
Non-US
Country
Canada
Vehicle
2018 challenger hellcat
Thread Starter #180
I'm not implying your lying at all, the trap speed delta just seems hard to swallow. Only looking for other variables that might have contributed. What you say about the stock box heat soaking is 100% correct and I've told people this over and over at the other forum. Many people swear that because the LMI has higher IAT temps when idling in traffic that the stock box is better but I've said time and again, the LMI's IAT's also go down much more rapidly once the car starts moving again because the stock box has so much plastic to cool down.

IAT's are less of an issue for me with the FI Interchiller but I do like some blower whine and don't want a restrictive intake at my power level. I've decided to try the AFE because I like the heat shield but its not a complete box like the JLT which just seems like another plastic box to cool down like the factory box. The AFE seems like the best of both worlds, similar to the LMI in that there's no plastic box to cool, but it does have a shield to block some engine heat unlike the LMI. We'll see but honestly I'm not expecting radically different results from the LMI.
I'm going to run all 3 intakes on a flow bench for comparison. An engine can only ingest so much air at WOT . But if you increase that demand then you need to increase the intake tract to match . That's what I think is happening on my car. The stock air box can't supply the volume the engine needs now after I modified it.

Sent from my BBF100-2 using Tapatalk
 




Top