its ugly but getting there... twin-charged SRT-6!!!
Re: its ugly but getting there... twin-charged SRT-6!!!
ok pardon me if this is a dumb question..... you got 14psi coming from the turbo then 14 pounds being pulled from the turbo and pushed in to the engine bye the supercharger.. I understand that if the 14 pounds coming from the turbo was compressed right when it got to the supercharger such as there being a valve that only opened once it got to 14psi then went into the supercharger but with the supercharger always pulling air into it from the turbo wouldn't that lower the air pressure inside the pipe coming from the turbo.. in other words the supercharger would suck some of the pressure into itself before it can get to 14 psi sort of like a boost leak.. or would them both being at the same psi would the supercharger let the turbo even compress the air the turbo is pushing
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Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Eric
ok pardon me if this is a dumb question..... you got 14psi coming from the turbo then 14 pounds being pulled from the turbo and pushed in to the engine bye the supercharger.. I understand that if the 14 pounds coming from the turbo was compressed right when it got to the supercharger such as there being a valve that only opened once it got to 14psi then went into the supercharger but with the supercharger always pulling air into it from the turbo wouldn't that lower the air pressure inside the pipe coming from the turbo.. in other words the supercharger would suck some of the pressure into itself before it can get to 14 psi sort of like a boost leak.. or would them both being at the same psi would the supercharger let the turbo even compress the air the turbo is pushing
Re: its ugly but getting there... twin-charged SRT-6!!!
at what ratio does the oem supercharger compress air though?
a supercharger normally takes atmospheric pressure (14.5psi here in most of ga, due to elevation) and compresses it by a ratio, normally rpm vs. airflow.
if you feed the supercharger already compressed air, it will compress it and heat it further.
a supercharger normally takes atmospheric pressure (14.5psi here in most of ga, due to elevation) and compresses it by a ratio, normally rpm vs. airflow.
if you feed the supercharger already compressed air, it will compress it and heat it further.
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Thumper SRT6
Just some corrections to the math:
14PSI boost is a pressure ratio of 1.95 --> (14 + 14.7) / 14.7
So PR1 from the turbo (1.95) compounded with the PR2 of the supercharger (1.95) is 1.95*1.95 = 3.80
Boost gauge will read:
BG = (PR1*PR2 - 1)*14.7
BG = (3.80 - 1) * 14.7 = 41.16 PSIG
This equation derived from the Pressure Ratio equation, then solving for Bgauge:
PR = (Bgauge + 14.7) / 14.7
PR * 14.7 = Bgauge + 14.7
PR*14.7 - 14.7 = Bgauge
(PR - 1)*14.7 = Bgauge
14PSI boost is a pressure ratio of 1.95 --> (14 + 14.7) / 14.7
So PR1 from the turbo (1.95) compounded with the PR2 of the supercharger (1.95) is 1.95*1.95 = 3.80
Boost gauge will read:
BG = (PR1*PR2 - 1)*14.7
BG = (3.80 - 1) * 14.7 = 41.16 PSIG
This equation derived from the Pressure Ratio equation, then solving for Bgauge:
PR = (Bgauge + 14.7) / 14.7
PR * 14.7 = Bgauge + 14.7
PR*14.7 - 14.7 = Bgauge
(PR - 1)*14.7 = Bgauge
edited original post
Last edited by ProjectMayhem; 07-19-2010 at 12:10 AM.
Re: its ugly but getting there... twin-charged SRT-6!!!
I think you need to just get a boost reading before the throttle body. Remember Waldig got an extra PSI of boost just by eliminating restriction with the dual intake. If you can maintain just 1 PSI to the SC inlet then you are not restricting air flow to it. Screw stuffing 14 PSI into the SC for now, just try to keep 1 PSI in front of it and then start turning it up with the waste gate later.
How are you dealing with the vacuum/PCV/brake booster? Check valves?
How are you dealing with the vacuum/PCV/brake booster? Check valves?
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by tunaglove
I think you need to just get a boost reading before the throttle body. Remember Waldig got an extra PSI of boost just by eliminating restriction with the dual intake. If you can maintain just 1 PSI to the SC inlet then you are not restricting air flow to it. Screw stuffing 14 PSI into the SC for now, just try to keep 1 PSI in front of it and then start turning it up with the waste gate later.
How are you dealing with the vacuum/PCV/brake booster? Check valves?
How are you dealing with the vacuum/PCV/brake booster? Check valves?
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Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Montana Crossfire
OK
Getting to the point after Yes it can work...
Will this thing be,
1. Drivable
2. self destructing
3. dependible
And or what are going to be the foreseeable problems once completed?
Getting to the point after Yes it can work...
Will this thing be,
1. Drivable
2. self destructing
3. dependible
And or what are going to be the foreseeable problems once completed?
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Eric
all i can say is im going to find out on all points
Looks like everyone is helping out and you are definitely blazing new ground for the XF crowd, my hat is off to you.
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Eric
with the supercharger always pulling air into it from the turbo wouldn't that lower the air pressure inside the pipe coming from the turbo..
Think of it this way your motor flows enough to produce 330 hp pulling in normal atmosphere.
That turbo is capable of up to 600hp
This motor will never be pulling in more air than the turbo can push into it. That why Atmosphere at the intake manifold increases aka BOOST.
I tried to simplify it to its basic concept does that help you understand why that wont happen?
Re: its ugly but getting there... twin-charged SRT-6!!!
yea thats a lot more simple
Originally Posted by ProjectMayhem
No because the turbo pushes more CFM than the motor + supercharger can take in an normal atmospheric pressure.(when the turbo is spolled up)
Think of it this way your motor flows enough to produce 330 hp pulling in normal atmosphere.
That turbo is capable of up to 600hp
This motor will never be pulling in more air than the turbo can push into it. That why Atmosphere at the intake manifold increases aka BOOST.
I tried to simplify it to its basic concept does that help you understand why that wont happen?
Think of it this way your motor flows enough to produce 330 hp pulling in normal atmosphere.
That turbo is capable of up to 600hp
This motor will never be pulling in more air than the turbo can push into it. That why Atmosphere at the intake manifold increases aka BOOST.
I tried to simplify it to its basic concept does that help you understand why that wont happen?
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Infinite
the brake booster source doesnt get its feed after the TB IIRC
the feed to the bov need to be after the tb or it wont work
the feed to the bov need to be after the tb or it wont work
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by GDC-SRT
With the sc doing its thing at lower RPMs, and the turbo kicking in @ higher RPMs,
You should have good power across the spectrum.
You may want to use some meth spray for cooling, as both of these air pumps make heat.
You should have good power across the spectrum.
You may want to use some meth spray for cooling, as both of these air pumps make heat.
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Eric
wheres the brake booster source come from then? It was opening from the vacuum when i would let off the gas. not sure how els i would put it on hmmm
because they are supercharged and tend to have constant positive manifold pressure,it wouldnt function the same way after the tb so its probably before the throttle body somewhere on the intake. maybe an srt owner can chime in.
if thats the case, any pressure differential between the charge pipe and vacuum source wouldnt exist, so it would never open.
Re: its ugly but getting there... twin-charged SRT-6!!!
Originally Posted by Infinite
on the na's its after the tb on the intake manifold. not sure where it is on the SRT's.
because they are supercharged and tend to have constant positive manifold pressure,it wouldnt function the same way after the tb so its probably before the throttle body somewhere on the intake. maybe an srt owner can chime in.
if thats the case, any pressure differential between the charge pipe and vacuum source wouldnt exist, so it would never open.
because they are supercharged and tend to have constant positive manifold pressure,it wouldnt function the same way after the tb so its probably before the throttle body somewhere on the intake. maybe an srt owner can chime in.
if thats the case, any pressure differential between the charge pipe and vacuum source wouldnt exist, so it would never open.