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which is better a supercharger or twin turbo kit. How about the tuning between both of them. Also outta of those two which one has a longer engine life.
Expected horsepower gains to cost to engine line.
 

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Turbo's are much more efficient these days, and will easily outperform a Centrifugal blower when done properly. Be prepared to spend some cash though.....
Engine life depends on too many factors, but a safe tune is key to say the least.

I run a Centrifugal at 12lbs on my 94 stang - and am very happy with the setup, but I have enough money in that car now to pay cash for an SRT10. Would I trade my setup for T/T's?? Ubetcha.
 

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Well another point to keep in mind is turbo lag vs. whine all the time with a supercharger.
 

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Turbo lag is old technology...the newer more advanced unit's don't have the old "lag" and they are extremely efficient. Take a look at what some of the boy racer 4 bangers are doing with Turbo's, or even the SRT4!!
Turbo's rock...

The S/C head unit I had on my stang originally was a belt driven unit (Powerdyne BD-11a) and there was no whine at all, in fact, I couldn't hear it....so I upgraded the head unit to a gear driven unit that announces to the world there is a blower under the hood!! :biggrin:
 

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turbohips said:
Well another point to keep in mind is turbo lag vs. whine all the time with a supercharger.
If done properly lag is NEVER an issue. Like 5point7 said, those days are over.

Here's the basic pro's and con's with supercharging and Turbo's

Superchargers have more parasitic loss from the crank shaft equalling about 30-50% less power than turbo's per PSI, so turbo's are more efficient at making power no matter what part of the power band.

Less under hood heat is created with a supercharger, but if the turbo is done right with proper location, coatings, wrappings, etc. It might not be an issue depending on climate.

Cost.....Turbo's will be more expensive typically by 100% more per installation though varying. This depends on who's doing them. Typically turbo kits are harder to get than supercharger kits since the R&D is more expensive and a custom turbo install could cost as much as 4 times as much as a typical off the shelf s/c kit.

Depending on the supercharger you will not get good low end torque normally assumed with a supercharger. A screw or roots style blower will give low RPM torque, and typical centrifugal s/c will not. it usually will only start producing boost past the 3000RPM mark and take full/near redline operation to achieve advertised max boost level.

Turbo's on the other hand can make peak boost through 80-90% of the RPM curve.

So basically turbo's are better and more efficient at making power, but they're more expensive, and create more heat.

Just like 5point7 said, I'd trade my s/c setup for turbo's, but I like having a/c and having 750RWHP is enough for me (that's my plan with my centri s/c in the future)
 

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To be fair, lag will always be there it all depends on the size/construction of the turbos, take for instance single turbo setup on a Supra, if one wants big horsepower lag will be previlant but there are things that can help with the lag such as small shots of Nitrous (electronically controlled), electric spoolers, etc. Ball bearing turbos spool much faster as well. That being said to put twins on this motor I would expect the max size of them to be T25's or 28's max (just not much more room under there).

5point7 said:
Turbo lag is old technology...the newer more advanced unit's don't have the old "lag" and they are extremely efficient. Take a look at what some of the boy racer 4 bangers are doing with Turbo's, or even the SRT4!!
Turbo's rock...

The S/C head unit I had on my stang originally was a belt driven unit (Powerdyne BD-11a) and there was no whine at all, in fact, I couldn't hear it....so I upgraded the head unit to a gear driven unit that announces to the world there is a blower under the hood!! :biggrin:
 

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aspendog said:
To be fair, lag will always be there it all depends on the size/construction of the turbos, take for instance single turbo setup on a Supra, if one wants big horsepower lag will be previlant but there are things that can help with the lag such as small shots of Nitrous (electronically controlled), electric spoolers, etc. Ball bearing turbos spool much faster as well. That being said to put twins on this motor I would expect the max size of them to be T25's or 28's max (just not much more room under there).
I will restate again this has to do with design and application. Depending on what you want.

Lag will not be an issue so long as it's designed for it's intended purpose, street or track.

Anyone running a big single turbo at a drag strip with a high stall converter won't have a problem with the turbo spooling on the line. Now a big turbo car on a road course will, but there again, it has to do with application. A smaller twin turbo setup is better for that.
 

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Twin turbos use to have a problem with tuning. Each turbo is set up for one side of the engine. Meaning each one runs a bank of 4 cylinders on the engine. The trouble you can have is one turbo could put out a little more boost than the other. You also must make sure than both sides of the engine are getting the same amount of fuel. And of course you have to make sure that you overcome the possible cooling problems. You are acually tuning two engines. The left half and the right half. Both must be in unison so that the engine is balanced.
I had several turbos in the past and I prefer the single turbo. Even with a ceramic bearing you are still going to have some lag time. The larger the turbo, the more lag. The smaller turbos are better for low end times, while the larger ones are going to give you better top end. In conclusion, I guess I vote for a single turbo or supercharger. Cecil...........
 

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Question - MDS, does it shut down 4 cylinders on one side or 2 cylinders on each side?
 

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How would MDS affect Turbo lag?
Switching from 8 to 4 pumps is going to reduce the volume of air and therefore the speed of the turbo. The when you switch back to 8 cylinders the turbo would have to spool up, right?
I don't know much about turbos but this seems logical.
 

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With regard to turbo lag - I watched a show recently where Gale Banks was installing a monster turbo on the '03 Cummins Turbo Diesel truck engine in Dodge pickups "Project Sidewinder". And he (and the show's host) claimed there was no lag at all, due to computer control of a variable geometry turbo - basically, a turbo that can change the angle of the "fins" to be more aggressive at low RPM, thereby moving more air and thus eliminating lag. Sounded awesome!!! (Just IMAGINE a truck making 500 HP and 1,000 lb/ft of torque!!! :D)

This cutaway illustration shows the Holset variable geometry turbocharger used on the Project Sidewinder Cummins compression ignition engine.



Goals

To establish Cummins compression ignition technology as powerful, clean, quiet, efficient and desirable – something the consumer wants in a light-duty truck or sports utility vehicle.

To position the brands of Cummins Engine Company, Holset Turbo and New Venture Gear as the technology leaders in this arena.

To use this advanced technology to establish new speed records in excess of 210 MPH using a compression ignition, turbocharged engine powering a Dakota pickup that is STREET-DRIVEN, TRACTABLE AND FUN.

Project Sidewinder




  • Banks Race Shop prepared Dodge Dakota Pickup with all creature comforts for highway driving
  • Cummins 2003 inline six cylinder compression ignition engine with common rail injection
  • Holset variable geometry turbocharger
  • New Venture Gear six speed gearbox
  • Wilwood braking system
  • Progress Group coilover spring/shock units
  • Banks engine modifications and turbo system
  • 700+ brake horsepower
  • 1200+ pounds-feet of torque
  • 210 mile per hour record speed at Bonneville
  • Establish 1/4 mile drag racing record for diesel
  • 20 miles per gallon fuel economy
  • Quiet running, low emissions
  • 100% highway drivability
  • Tow race equipment in trailer to Bonneville, drag races, etc
 

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maneval69 said:
How would MDS affect Turbo lag?
Switching from 8 to 4 pumps is going to reduce the volume of air and therefore the speed of the turbo. The when you switch back to 8 cylinders the turbo would have to spool up, right?
I don't know much about turbos but this seems logical.
I wasn't speaking of its affect on lag or lack of, I was thinking that if you were running a dual set up, and IF MDS turned off a bank, then there would be no exhaust to drive the impeller on that banks turbo. I would imagine that an entire bank is not shut down but select cylinders balanced on each side to prevent shake.
 

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There would be no problem of the turbos "feeding" only 4 cyls a piece because we have one throttle body on our intake, they put two turbos on a V engine because of the added backpressure, it unevenly loads the engine if a turbo is placed on one side of the exhaust and not the other.. People that do turbo installs on V engines with just one turbo typically go farther down the exhaust stream to where the two sides are joined together.

The biggest fear for me with turbos would be the valves in the Hemi... As I understand the valves for MDS are very different than the truck Hemi or the 6.1 has.. I believe our valves are light weight, in which we'd have to ask ourselves how they would do with the added heat and backpressure... Mainly heat..
 

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obiwan said:
Question - MDS, does it shut down 4 cylinders on one side or 2 cylinders on each side?
MDS deactivates 2 cyls on either side of the V.

Quite logical as it retains better power delivery as a V4, than as straight 4, carrying a parasitic straight 4, on the other bank, with possible balance problems, and vibration problems.

Cylinders shut down by MDS are 1, 7, 4 and 6.

This means that the theoretical 2 turbos would operate at reduced speed, and then spool up again after transitioning to V8 operation -- no problems.

If it was one bank shut down that would shut down one turbo, the other turbo on the full 4 cyl bank would operate normally. It could cause differential wear in the turbos.

Zilla
 

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Twin turbos are far superior to any belt driven supercharger, its all about efficiency and parasitic loses.

Turbo lag is a thing of the past, so don't even worry about it, especially with a twin turbo system.
 

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anyone have any feedback on remote mounted turbos? i think sts makes it or maybe cts. i guess they go under the car to assist in cooling them???????? good stuff or bad?????????
 
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