Twin Turbo Ford Raptor is HERE!!!

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Cleave

FRF Addict
Joined
Apr 23, 2013
Posts
3,359
Reaction score
948
Location
Oxnard, Ca
Ck, is that a twin turbo feeding a supercharger? I've always wanted to see what the outcome of having the supercharger feed the turbine side of the turbos would be
 

Cleave

FRF Addict
Joined
Apr 23, 2013
Posts
3,359
Reaction score
948
Location
Oxnard, Ca
But superchargers have better flow volume than an engine, I'm talking about having the supercharger take the place of the exhaust gas to spool up the turbos, then you should have instant boost but you still have the advantages of running turbos
 

sabumaru

FRF Addict
Joined
Mar 9, 2013
Posts
1,221
Reaction score
271
Location
Nijmegen, The Netherlands
But superchargers have better flow volume than an engine, I'm talking about having the supercharger take the place of the exhaust gas to spool up the turbos, then you should have instant boost but you still have the advantages of running turbos

Hmmm
Not sure
Cold air tubo charging
Could work
But dependable on the weight of the supercharger
 

pirate air

will plunder your booty
Supporting Member
Joined
Jul 11, 2010
Posts
4,253
Reaction score
1,379
Location
Texas
But superchargers have better flow volume than an engine, I'm talking about having the supercharger take the place of the exhaust gas to spool up the turbos, then you should have instant boost but you still have the advantages of running turbos

You realize part of a turbos function is thermal energy; heat expansion from the exhaust applied across the turbine. It's not all about flow across the turbine. You'd have to have one big blower to even get the turbo to spin at a productive speed, what ever hp you gained by turbocharging would be negated by turning the big ass blower.

With the way compounds are set up with turbo over supercharger, you accomplish low speed boost with a positive displacement style supercharger but still have big end power from a larger turbo/s. Compound supercharging and turbocharging work, but its not practical from several standpoints. Turbo over turbo in diesels are about the only practical compound application.
 
Last edited:

Cleave

FRF Addict
Joined
Apr 23, 2013
Posts
3,359
Reaction score
948
Location
Oxnard, Ca
So you're saying due to heat expansion of the exhaust gas an engine produces more volume of gas than a supercharger of equivalent displacement can? So if you had a 2.8l engine and a 2.8l supercharger the engine would output more exhaust volume than the supercharger would output air volume?
 

pirate air

will plunder your booty
Supporting Member
Joined
Jul 11, 2010
Posts
4,253
Reaction score
1,379
Location
Texas
So you're saying due to heat expansion of the exhaust gas an engine produces more volume of gas than a supercharger of equivalent displacement can? So if you had a 2.8l engine and a 2.8l supercharger the engine would output more exhaust volume than the supercharger would output air volume?

I dont look at it as volume, but energy. The engine exhaust has left over thermal energy. Lots of left over (virtualy free) thermal energy.... The supercharger discharge has very little thermal energy unless you start compressing the air an extreme amount, which again will require that much bigger of a big blower. Even if the volumes are the same energy between them is not. Thermal energy plays a huge role.

For instance, take manual transmission turbo car. With the car out of gear rev the engine to 6 grand. Does the turbo spool? No. And if it does spools it builds very low psi. Now put the car in gear and stomp on it till the engine reaches 6 grand. Does the turbo spool? Yes. Why? Both times the engines rev'd to 6 grand moving the same amount of air right? Well, the thermal energy was different. A loaded engine discharges more heat/thermal energy out the exhaust forcing the turbo to spool. This is the same reason people will use a two step ignition to spool a turbo off the line. A two step pulls spark completely on selected cylinders making the exhaust overly rich with un burnt fuel. The fuel burns in the exhaust manifold/turbo header creating heat which spools the turbo with out actually loading the engine/moving the car.
 
OP
OP
CK@UPP

CK@UPP

Member
Joined
Aug 27, 2013
Posts
32
Reaction score
68
You realize part of a turbos function is thermal energy; heat expansion from the exhaust applied across the turbine. It's not all about flow across the turbine. You'd have to have one big blower to even get the turbo to spin at a productive speed, what ever hp you gained by turbocharging would be negated by turning the big ass blower.

With the way compounds are set up with turbo over supercharger, you accomplish low speed boost with a positive displacement style supercharger but still have big end power from a larger turbo/s. Compound supercharging and turbocharging work, but its not practical from several standpoints. Turbo over turbo in diesels are about the only practical compound application.
^ THIS


Another way to think of it is: an engine = pump, supercharger = bigger pump, turbo = biggest pump.


Now if you put a tiny Eaton M90 on a Merlin Big block, it doesn't really matter how fast you spin it, it just won't feed enough air to even allow the engine to breath. So the biggest pump HAS to be the first in the system. You could get a SC that is bigger than the turbos, but since you're already wasting the energy to spin the SC, and you already get the low end.....why have the turbos at all?

The SC's size is rather irrelevant, it's simply a catalyst for the system, something to jump start the turbos, and get better low end than you normally would. Once the turbos compress the air, the SC will compound it (compress it more), and feed the engine. But the turbo being the first pump in the system has to take air at ambient pressure and flow it through, so you can never outflow the first pump.

PUMP>Pump>pump



CK
 
Top