• 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!


Stock Boost Questions

AeroF16

2000 Posts Club
Donating Member
Member ID
#2826
Messages
2,197
Reactions
7,014
Likes
252
City
Phoenix
State
AZ
Country
United States
Vehicle
2016 Challenger Hellcat
#1
It's already been a long week, I'm working my way through a few adult beverages and don't feel like putting my engineering degree to use, so I'm just going to ask here.

Why do I only see 9 psi on my performance pages under full load? 4th gear pulls, 5th gear pulls, 6th gear pulls (A8) doesn't seem to make a difference.

Completely stock 2016 Challenger Hellcat. Located in Phoenix, so about 1000' MSL, and 110* days.

I assume the 11.6 psi the factory quotes is at standard temperature and pressure, but didn't think 40 degrees and 1000' would drop it that much.
 


Paladin06

4000 Posts Club
Founding Member
Premium Account
U.S. Army Veteran
Donating Member
HFCOTM
Member ID
#1080
Messages
4,662
Reactions
24,173
Likes
302
City
Clarksville
State
TN
Country
United States
Vehicle
2015 Challenger Hellcat/2019 Challenger Redeye
#2
There are many variables. Altitude, temperature, barometric pressure. 11psi is best conditions.
 


ACMAVRO

2000 Posts Club
Founding Member
Donating Member
11 Second Best E/T
HFCOTM
Member ID
#1214
Messages
2,174
Reactions
5,105
Likes
302
City
Ocean Springs
State
MS
Country
United States
Vehicle
2015 Challenger HC M6
#3
I’m at sea level on hot, humid Mississippi gulf coast and I get 10
 


Paladin06

4000 Posts Club
Founding Member
Premium Account
U.S. Army Veteran
Donating Member
HFCOTM
Member ID
#1080
Messages
4,662
Reactions
24,173
Likes
302
City
Clarksville
State
TN
Country
United States
Vehicle
2015 Challenger Hellcat/2019 Challenger Redeye
#4
I’m at sea level on Mississippi gulf coast and I get 10
Yep and you have horrible humidity. Lol
 


fumanchu182

3000 Posts Club
Vendor
Premium Account
U.S. Navy Veteran
Donating Member
9 Second Best E/T
HFCOTM
Member ID
#2366
Messages
3,488
Reactions
8,484
Likes
302
City
Pasadena
State
MD
Country
United States
Vehicle
2015 Challenger SRT Hellcat
#5
Map pressure - barometric pressure is the main part of the equation. Throw in aircharge, aircharge temp, grains of water in air and size and humidity...
 


OP
A

AeroF16

2000 Posts Club
Donating Member
Member ID
#2826
Messages
2,197
Reactions
7,014
Likes
252
City
Phoenix
State
AZ
Country
United States
Vehicle
2016 Challenger Hellcat
Thread Starter #6
Map pressure - barometric pressure is the main part of the equation. Throw in aircharge, aircharge temp, grains of water in air and size and humidity...
Map Pressure...

I don’t want to be the one to break it to you, but I think you're suffering from RAS. I bet you take money out of the ATM machine too 😀

https://en.m.wikipedia.org/wiki/RAS_syndrome
 


Mean Cat

4000 Posts Club
Founding Member
Donating Member
9 Second Best E/T
HFCOTM
Member ID
#997
Messages
4,981
Reactions
9,435
Likes
302
City
Houston
State
TX
Country
United States
Vehicle
2017 Challenger Hellcat
#7
It's already been a long week, I'm working my way through a few adult beverages and don't feel like putting my engineering degree to use, so I'm just going to ask here.

Why do I only see 9 psi on my performance pages under full load? 4th gear pulls, 5th gear pulls, 6th gear pulls (A8) doesn't seem to make a difference.

Completely stock 2016 Challenger Hellcat. Located in Phoenix, so about 1000' MSL, and 110* days.

I assume the 11.6 psi the factory quotes is at standard temperature and pressure, but didn't think 40 degrees and 1000' would drop it that much.
Because of where you live AZ. , high altitude vs. at sea level & hot weather kills boost & hp.
 


Last edited:

Phast Hemi

Active Member
Founding Member
Member ID
#1092
Messages
315
Reactions
620
Likes
67
City
SHELBY TOWNSHIP
State
MI
Country
United States
Vehicle
2019 Dodge Chall SRT Hellcat Redeye
#8
It's already been a long week, I'm working my way through a few adult beverages and don't feel like putting my engineering degree to use, so I'm just going to ask here.

Why do I only see 9 psi on my performance pages under full load? 4th gear pulls, 5th gear pulls, 6th gear pulls (A8) doesn't seem to make a difference.

Completely stock 2016 Challenger Hellcat. Located in Phoenix, so about 1000' MSL, and 110* days.

I assume the 11.6 psi the factory quotes is at standard temperature and pressure, but didn't think 40 degrees and 1000' would drop it that much.
Normal for that weather/climate.
 


fumanchu182

3000 Posts Club
Vendor
Premium Account
U.S. Navy Veteran
Donating Member
9 Second Best E/T
HFCOTM
Member ID
#2366
Messages
3,488
Reactions
8,484
Likes
302
City
Pasadena
State
MD
Country
United States
Vehicle
2015 Challenger SRT Hellcat
#9

BULL

Oh NO! Not that guy!
Staff Team
Founding Member
U.S. Marine Veteran
Donating Member
HFCOTM
Wiki Contributor
Member ID
#1079
Messages
14,587
Reactions
44,742
Likes
402
City
Weld County
State
CO
Country
United States
Vehicle
MY16 M6 Challenger Hellcat
HFCOTM
View Images
#10
Or how about RPMs?


How many Ms?


:unsure:

:LOL:
 


BULL

Oh NO! Not that guy!
Staff Team
Founding Member
U.S. Marine Veteran
Donating Member
HFCOTM
Wiki Contributor
Member ID
#1079
Messages
14,587
Reactions
44,742
Likes
402
City
Weld County
State
CO
Country
United States
Vehicle
MY16 M6 Challenger Hellcat
HFCOTM
View Images
#11
It's already been a long week, I'm working my way through a few adult beverages and don't feel like putting my engineering degree to use, so I'm just going to ask here.

Why do I only see 9 psi on my performance pages under full load? 4th gear pulls, 5th gear pulls, 6th gear pulls (A8) doesn't seem to make a difference.

Completely stock 2016 Challenger Hellcat. Located in Phoenix, so about 1000' MSL, and 110* days.

I assume the 11.6 psi the factory quotes is at standard temperature and pressure, but didn't think 40 degrees and 1000' would drop it that much.



Using any method that suits you, including pulling it from your work "vehicle", determine the DA for the moment you're referencing.


I'm typically at 7500DA or higher, and I see 8psi most of the time, once in a great while I see a flicker of 9psi.


The :poop: part is the 100hp that goes along with that...


:mad:
 


OP
A

AeroF16

2000 Posts Club
Donating Member
Member ID
#2826
Messages
2,197
Reactions
7,014
Likes
252
City
Phoenix
State
AZ
Country
United States
Vehicle
2016 Challenger Hellcat
Thread Starter #12
Just calculated current DA using the National Weather Service calculator and pulled the variables from the current observation on base here.

3500' DA right now. So Bull you're over double that and see similar performance as I am. Still seems odd to me.
 


BULL

Oh NO! Not that guy!
Staff Team
Founding Member
U.S. Marine Veteran
Donating Member
HFCOTM
Wiki Contributor
Member ID
#1079
Messages
14,587
Reactions
44,742
Likes
402
City
Weld County
State
CO
Country
United States
Vehicle
MY16 M6 Challenger Hellcat
HFCOTM
View Images
#13
Just calculated current DA using the National Weather Service calculator and pulled the variables from the current observation on base here.

3500' DA right now. So Bull you're over double that and see similar performance as I am. Still seems odd to me.

If you're pulling a solid 9psi, then that's a decent bit better than me.

Remember our scale is a bit non-linear and also the resolution leaves a lot to be desired.
 




Top