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
^ 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

I just never understood turbo feeding a supercharger, a supercharger has a fixed displacement, the supercharger is a restriction for the turbos and would basically negate most gains of putting the turbos on the engine in my opinion, my idea with having the supercharger spool the turbo was that I thought a supercharger could spool the turbos better than an engine could and would be able to spool it at idle, getting rid of lag but still providing the better flow of turbochargers at the top end
 

pirate air

will plunder your booty
Supporting Member
Joined
Jul 11, 2010
Posts
4,253
Reaction score
1,379
Location
Texas
I just never understood turbo feeding a supercharger, a supercharger has a fixed displacement, the supercharger is a restriction for the turbos and would basically negate most gains of putting the turbos on the engine in my opinion, my idea with having the supercharger spool the turbo was that I thought a supercharger could spool the turbos better than an engine could and would be able to spool it at idle, getting rid of lag but still providing the better flow of turbochargers at the top end

It sounds weird at first but you have to remember the air is already compressed by the turbo/s once it hits the smaller supercharger. The supercharger has no idea the air is compressed above atmosphere. It just takes the air and compresses it more than what the turbo gave it.

At low speed the supercharger is more efficient than the larger turbo. Essentially the supercharger draws the air through the large turbo while it spins and basically does nothing but allow air to move by at this point. This is where the blower brings on the low end power.

As the rpm increases the supercharger drops efficiency and loses the race with the engine. Boost starts to drop off because the supercharge can't keep up. The engine loses power. This is where the turbo gets involved. Once it starts to spool, it compresses air against the inlet of the supercharger. The supercharger takes the pre compressed air and compresses it more allowing it to keep up with engine demand. The turbo at this point is doing a lot of the compressing work for supercharger.
 
OP
OP
CK@UPP

CK@UPP

Member
Joined
Aug 27, 2013
Posts
32
Reaction score
68

so exhaust makes them spin I need turbos 101 or just tell me so shut up and look or gtho[/quote]
Maximum Boost- book by Corkey Bell - amazing book w/lots of great info!



[quote="Cleave, post: 579980"]I just never understood turbo feeding a supercharger, a supercharger has a fixed displacement, the supercharger is a restriction for the turbos and would basically negate most gains of putting the turbos on the engine in my opinion, my idea with having the supercharger spool the turbo was that I thought a supercharger could spool the turbos better than an engine could and would be able to spool it at idle, getting rid of lag but still providing the better flow of turbochargers at the top end[/quote]

You can't look at it as Turbo, SC, Engine....look at it as 3 pumps. That's all they are. Now putting a SC on an engine creates a restriction for the SC right? That's why the pressure backs up and creates boost. Same thing in the T/SC/E example.

The SC doesn't necessarily flow a certain amount of LB/min of air, it flows boxes, cubes of air. Cubic feet per min. Now what is in those boxes? Could be air, could be water, could be ranch dressing! But it will take that box of 'X' and pass it through. So what if that box contained already compressed air? Now when you stack that against an engine that doesn't flow, you get boost.

Ok, take your 5L engine. ******** a 5L blower but spin it 2x the speed of the engine. Now it's essentially flowing 10L of air into an engine that can only consume 5L, so you're doubling the airflow (just happens to = ~14psi of boost). Now strap a turbo in front of that and push 14psi against the SC. Since the air is already "pre-compressed" the SC will still take those boxes of air and pass them through, and since the SC is pushing boxes through at 2x what the engine can consume, the end result is 28psi against the engine.

The turbos will be flowing 20L of air through them, but only at a pressure of 14psi.
It would be similar to running a 10L engine with turbos alone pushing 14psi.

(Of course there's ALOT more that goes into this, but this is the basic generic principal.)


CK
 

Wilson

FRF Addict
Joined
Jan 27, 2012
Posts
26,217
Reaction score
10,317
Location
South Dakota
I was thinking the other way around the supercharger would feed the turbo but I figured out that is what a blower is dose.

---------- Post added at 10:01 PM ---------- Previous post was at 09:56 PM ----------

I was also thinking a turbo only blew exhaust out. Or is there two types of turbos?
 

Maxx2893

Rock and Roll Offroad
Supporting Member
Joined
Mar 13, 2011
Posts
5,942
Reaction score
1,180
Location
Burleson, TX
No, the exhaust spins the turbo, which sucks air in on the other side and then blows the air into the engine.
 

sabumaru

FRF Addict
Joined
Mar 9, 2013
Posts
1,221
Reaction score
271
Location
Nijmegen, The Netherlands
To me there is a BIG difference between "Off-Road" and "Extreme Off-Road". It appears that most on this site are "Extreme". When developing this kit I had no idea that so many of you jumped these things, nor that it was even possible to damage the skid shield.





I am more than game for this idea. We're starting to branch out more and more and develop new kits. We're just now completing one for the new Camaros with top mount turbos, complete with manifolds.

Unfortunately the Raptor we did belongs in Nebraska. But if any of you are local here in CO, or are willing to travel and donate your truck to the cause....I am more than willing.

Did any one sign upmyet ??
 
Top