Turboing vs. Supercharging - Pros and Cons

[MRJUCY]

Originally Posted by Steffo

No screw-type supercharger will ever be as efficient as a turbocharger.. the extra heat and parasitic loss is inveitable. Just read the site Biggoggs listed.. they've got it spot on.

Thats the same as saying all DOHC engines are more efficient then any pushrod motor it's pure BS

[Steffo]

Originally Posted by MRJUCY

Thats the same as saying all DOHC engines are more efficient then any pushrod motor it's pure BS

Rightio then, you believe that a device which sits atop the engine, uses the engine's crankshaft to be driven, and then forces compacted, frictionally heated air into the engine to be more efficient then a device which sits anywhere in the engine-bay you want it to, uses already expelled gasses to drive it and forces re-used and less frictionally heated air, cooled (much easier to setup a turbo intercooled setup then screw/roots intercooled) into the engine at a much higher rate anyway, which is also capable of sustaining far high RPM.

With Turbo vs S/C, there is a clear winner. DOHC vs Pushrods is unclear.. sure, the heads may flow slightly better.. but then there's immense size, structural integrity and several other factors that come into play. Turbo vs Screw/Roots S/C is a no-contest victory to turbo.

[Biggoggs]

Whether supercharged or NA, your engine is still going to be producing torque and exhaust gasses. By using a turbo, you're effectively using more of the engine. How is this `pure BS' in clear physics?
I guess you could say superchargers are like bicycle-powered air conditioners. While it does in fact cool you down, it's not as efficient as, eg, one that runs off the heat you're already making

[MRJUCY]

Hmm you're showing how little you know about the product by simply stating that it sits on top on the engine which is of course popular but by no means neccesary.
With the autorotor there is very little in the way of friction as the rotors never touch each other or the case meaning it produces cooler air then other means hence they often run without an intercooler but they can be if needed easily enough.

[MITCHAY]

Theres got to be a reason why DOHC engines are becomming more common. If they were worse then why would companies build them?

Yes TURBO!!!! sound awesome aswell. So do S/C but i prefer turbos. Just seems that turbos have more pros than cons.

[dynosteve]

Originally Posted by geckoxr8

yeah, what is pro charger?

A pro-charger is a cross between a turbo and a supercharger, it's belt driven but has both a turbo and a supercharger inpeller inside, these are what we fit to everycar these days and go straight onto a std motor, if it's tuned right with a good fuel system and water injection there is no need to pull a motor apart to strenghten anything unless your chasing hugh power.

[jonbays]

There is a lot of difference between brands of turbo's and superchargers and your application is what should decide which is best.

I have been looking into the next move for my N/A auto daily driver nad for me its not a turbo its got to be a supercharger and the procharger is what I consider the best for low pressure street performance.

Of course a Vortech for some serious drags strip action would be good and a Garett turbo for track or dyno day competion would also be good.

The trick is working out what you really want. Accepting that you build an engine up for a specific purpose and it will not be good at everything. then doing it properly and not cutting corners on cost on things that matter when it blows up you will kick yourself.

[Steffo]

An ATI Pro-Charger is a Centrifugal supercharger, just like a Vortech or Powerdyne or Paxton NOVI 2000 etc etc. http://www.ProCharger.com

As for the forced induction efficieny battle, whether you like it or not MRJUCY, Turbochargers are the most efficient form of forced induction. A properly set-up turbo system will make more torque down low then a supercharger, more power, and sport a better powerband. And you will also have much cooler intake temps. Plus they have the capacity for higher flow then a positive displacement blower ever will, especially for street applications.

[Casper]

Originally Posted by Steffo

An ATI Pro-Charger is a Centrifugal supercharger, just like a Vortech or Powerdyne or Paxton NOVI 2000 etc etc. http://www.ProCharger.com

As for the forced induction efficieny battle, whether you like it or not MRJUCY, Turbochargers are the most efficient form of forced induction. A properly set-up turbo system will make more torque down low then a supercharger, more power, and sport a better powerband. And you will also have much cooler intake temps. Plus they have the capacity for higher flow then a positive displacement blower ever will, especially for street applications.

Sound like crap though. Give me the "hair on end" scream of a Supercharger over the gay fart "pfffffttt" of a turbo anyday! Bugger what makes more power, give me the SOUND!

(this is a joke post peoples....dont even bother to start a shit fight over it)

As for your options B2TF, I honestly think a turbo is the only real choice on a 4 cylinder, it is almost a perfect match. High revs and turbo's live well together.

[Laminge]

Ahhh Stefo

I will take a correctly tuned blown car over a correctly tuned turbo anyday!

Mind you I can get mine to go Pfffft!!!!

[dansedgli]

Originally Posted by Laminge

Ahhh Stefo

I will take a correctly tuned blown car over a correctly tuned turbo anyday!

Mind you I can get mine to go Pfffft!!!!

Any particular reason why, Gary?

[Laminge]

Personal Choice

I just cannot see myself driving a Turbo at the drags, and I just love the feel of a blown car compared to a T

Nothing more

[MITCHAY]

Ive been in a TT Zed and it ****ing awesome. Best motoring experience in my life. Would be keen to go in a blown V8 and experience the other side of forced induction if given the chance. Ive got to get along to some of these meets and get the atmosphere of it all. Just dont have the time in the present situation as i work all day every weekend.

[SpoolMan]

Gary it might be time for a drive of the Twin Turbo Boss.
i have been lucky enough to drive Rods TT and its like driving a bullet, put your foot down the response of the TT is like a high H/P motorcycle..

[b2tf]

Alrighty, without wanting to end the debate, Im in need of yet more info from those in the know about these sorts of things.
Im going to post this in the relevant forum but i thought i may as well ask here.

A few things:-

* Pretty much narrowed it down to Turbo but after dynosteve's post about ProChargers they do sound like an option to consider. I dont know much about the strength of the Zetec Engine but I imagine a boost application would over time result in something going bang. Therefore if a Procharger can give more power without the need to upgrade engine internals (im not looking for huge figures) it may be the way to go.

* I want the benefit to be felt throughout the whole rev range - I dont want a car that is a slug down low but a rocket up in high revs. This thing does find it difficult to get moving so I want to remove that as much as possible - Im not sure what I can do about this but it's definately something I am aiming to resolve. Im assuming this means I would be after a reasonably flat torque curve? (not sure).

* I was having a look at Fordracingparts.com last night (Genuime Ford/SVT developed performance parts) and they do sell a Supercharger kit for Focus, albeit US spec versions but I am unsure as to the extent of the differences between US and AU spec Foci, or if there even are any. Couldnt find a Turbo kit though.


* Where the hell do you mount an intercooler on a Focus?! There isnt much room in the bay and the front bar would need major modification to allow a decent airflow. Any ideas?

[MITCHAY]

Would it be possible for a top mount and a scoop? Dont know if you could do it but are side mounts an option?

[b2tf]

I really dont know but as the engine is mounted horizontally it doesnt leave a lot of room. The Ford US Supercharger kit actually had the charger itself above the engine (if youre looking at the engine bay front on, the charger is up closer to the firewall behind the engine) so that may be how it has to go, i dont know.

[MITCHAY]

Know some one with a N15 SSS with GTIR engine in it. Top mount with bonnet scoop. Goes hard

[paul7v7]

Originally Posted by back2thefutura

Alrighty, without wanting to end the debate, Im in need of yet more info from those in the know about these sorts of things.
Im going to post this in the relevant forum but i thought i may as well ask here.

A few things:-

* Pretty much narrowed it down to Turbo but after dynosteve's post about ProChargers they do sound like an option to consider. I dont know much about the strength of the Zetec Engine but I imagine a boost application would over time result in something going bang. Therefore if a Procharger can give more power without the need to upgrade engine internals (im not looking for huge figures) it may be the way to go.

* I want the benefit to be felt throughout the whole rev range - I dont want a car that is a slug down low but a rocket up in high revs. This thing does find it difficult to get moving so I want to remove that as much as possible - Im not sure what I can do about this but it's definately something I am aiming to resolve. Im assuming this means I would be after a reasonably flat torque curve? (not sure).

* I was having a look at Fordracingparts.com last night (Genuime Ford/SVT developed performance parts) and they do sell a Supercharger kit for Focus, albeit US spec versions but I am unsure as to the extent of the differences between US and AU spec Foci, or if there even are any. Couldnt find a Turbo kit though.


* Where the hell do you mount an intercooler on a Focus?! There isnt much room in the bay and the front bar would need major modification to allow a decent airflow. Any ideas?

check out the specs of the focus RS and see where they mounted the intercooler on that...

[MRJUCY]

Originally Posted by Steffo

As for the forced induction efficieny battle, whether you like it or not MRJUCY, Turbochargers are the most efficient form of forced induction. A properly set-up turbo system will make more torque down low then a supercharger, more power, and sport a better powerband. And you will also have much cooler intake temps. Plus they have the capacity for higher flow then a positive displacement blower ever will, especially for street applications.

Whatever if I wanted to go forced induction I'd be quite happy to have boost at idle, full boost by 2000rpm & still have full boost at 6000rpm without any change of temperature or volumetric efficiency anywhere through the range & can live with the up to 6hp it's costing me to drive & 10F per psi discharge temp pre intercooler

[Steffo]

Originally Posted by MRJUCY

Whatever if I wanted to go forced induction I'd be quite happy to have boost at idle, full boost by 2000rpm & still have full boost at 6000rpm without any change of temperature or volumetric efficiency anywhere through the range & can live with the up to 6hp it's costing me to drive & 10F per psi discharge temp pre intercooler

You can have that, and your increased heat, increased frictional power loss, inefficiency at high rpm (and low really). Meanwhile.. I'll enjoy increased power and torque, increase in top end power and low end power, excellent efficiency throughout the rpm range and an awesome powerband... and no frictional losses (Gotta love not having to tie a belt to some pulleys to use a turbo... spent exhaust gasses being re-cycled basically).

I guess you can keep thinking that a belt-driven supercharger is as good as, or better then a turbocharger.. back on Earth, it isn't, never was and never will be. _

[Casper]

Originally Posted by Steffo

You can have that, and your increased heat, increased frictional power loss, inefficiency at high rpm (and low really). Meanwhile.. I'll enjoy increased power and torque, increase in top end power and low end power, excellent efficiency throughout the rpm range and an awesome powerband... and no frictional losses (Gotta love not having to tie a belt to some pulleys to use a turbo... spent exhaust gasses being re-cycled basically).

I guess you can keep thinking that a belt-driven supercharger is as good as, or better then a turbocharger.. back on Earth, it isn't, never was and never will be. _

Sorry Steffo but you have some good points and some wrong points.
I will say that on a road car a turbo has probably got all the better points however it still has some drawbacks. The main problem being that there is always a compromise, and in the turbo’s case its lag. To stop lag you need a smaller turbo to spool up faster. Do that and you lose top end. To get top end you get lag. Somewhere there is a compromise. The way around this? Twin turbos that work in sequence of course, best of both worlds….the compromise being cost…BIG cost.

The other issue with turbos is to make a good system work on a larger sized engine. That’s not to say it cant, its just to say it is an expensive exercise. It’s simply far more difficult to work it. Most larger engines require a LARGE amount of intake but rev relatively slowly. So, you have an issue of getting the right size turbo(s) to both feed enough air and to spool up fast enough. Once again, twin is good (like the APS setup), once again, cost is bad.
So, for a road car I will agree turbos are the more effective however the bigger the engine, the more you have to accept a big bill or a compromise.
As for “frictionally heated air”, is that going to be more or less than air compressed in a unit that is so superheated by exhaust gasses that the need for an intercooler (and associated piping) is basically mandatory for decent performance? Piping = space, that space has to be pressurized meaning it takes even more time to get to the intake under pressure…meaning more lag.

Now, getting to you point specifically based on drag cars, top fuelers, funny cars and the like. The supercharger takes 800hp based on your assumptions so removing the belt would free this up immediately. That’s probably close enough to correct HOWEVER lets look at the whole picture here. Yes, it takes 800hp to run the supercharger but the net effect of that supercharger is 6500hp at the fly. So by freeing up the belt and running it on exhaust gasses it would be 7300hp? NOPE! The reasons are simple. All funny cars and top fuelers have basically no significant exhaust restrictions at all. So if you were to channel all that exhaust through a maze of pipes to spin a couple of turbos how much backpressure and power loss would that cause? 800hp…I’m betting more. Then of course, as the air is now superheated it needs to be cooled..intercooler… HUGE INTERCOOLER…more restriction and, more importantly, LAG!. Not to mention a MASSIVE aero wall to push down the track.
Finally, lets look at the race itself and, for arguments sake, say you have more power from the turbos. Lets look at how that poer would react in the extreame conditions of a race.
Theres no time to “spool up” on the line, it’s a heads up race. So you line up, green light and your off. About 60” down the track the turbos finally spool up to pressure and an extra 2000 or 3000hp hits the drivetrain. (This doesn’t happen with a Eaton SC as they are at full boost from idle, the powers already there). So what happens to a drag car when 2000hp hits the driveline? Well, at that point the car is already hooked up and moving…fast. Bring on the turbos and one of 3 concievable things will happen.
1. Instant traction loss… that would be the least destructive of the 3 too.
2. Instant driveline grenade…ouch
3. Instant traction loss, driveline grenade and loss of total control. Now the walls of a drag strip are supported be the state it is in… it isn’t moving..MEGA OUCH.

As you can see, in a strictly competition based drag race concept, the Supercharger MAY not have the ultimate power (although I expect it does) but it has the drivability and control that is mandatory for massive HP cars running on the absolute knifes edge.

In the end they both are compromises however to decree that a turbo is better than a Supercharger in all respects, all cases and all applications is simply wrong.

[dansedgli]

Let me just add that a turbo spooling and giving postive pressure does not rely on the revs of an engine. It is the load on an engine that will spool a turbo. A decent sized turbo will not spool in neutral no matter what the revs are.

I can cruise at 180 kms at 4000rpm (as an example) and not be on boost. Not many people realise this.

Also on a big engine lag is simply not an issue if the setup is done correctly. I have boost by 2000rpm in the AU. With a 700hp turbo. On smaller cars then yes it can be an issue but when you fit a 600hp turbo to a 2 litre engine what do you expect :(

A drag car will run a transbrake yes? A turbo car will spool up quickly on a transbrake. I believe geea can leave the line on nearly full boost in his car. Its all about matching the combo you have.

On a six or 4 cylinder I would take a turbo any day now that there is more of them around.

If room or engineering wasnt an issue I would do the same on an 8. But now that I have had to deal with getting a car engineered and passing emissions my only choice would be a supercharger unless someone can give me a turbo kit that meets all the required ADR's like CAPA have done with some of their kits.

[M14A-Mclaren]

So what and how do anti-lag systems work?

[Casper]

Basically all I was trying to point out is that, in some cases, the Supercharger is the better option. Be it requirements of the car, cost, packaging, emmissions or whatever, the Supercharger is a valid option in some cases and can be the better option as well.

Personally, for a small car, the turbo is the better option on the road for sure but for Steffo to say:

I guess you can keep thinking that a belt-driven supercharger is as good as, or better then a turbocharger.. back on Earth, it isn't, never was and never will be.

is simply wrong and narrow minded.

[Steffo]

Originally Posted by M14A-Mclaren

So what and how do anti-lag systems work?

Anti-Lag Systems (ALS) basically allow unburnt fuel to enter the exhaust tubing, where it explodes due to the high exhaust temperature.. and those explosions keep the turbo spinning.. allowing you to run insanely high boost at idle..

http://www.rallycars.com/Cars/bangbang.html

Good article there.

[RED_EL_XR8]

Originally Posted by Steffo

I guess you can keep thinking that a belt-driven supercharger is as good as, or better then a turbocharger.. back on Earth, it isn't, never was and never will be. _

Which earth is this? The one with Seven moons you drew on your pencil case, beside you picture of the 1.3L Quad Turbo you think Ford are Fools for not building.

The assertion that turbo is always better is ignorant to the extreme, there are valid reasons for use of both techologies, and there as just as many valid reasons to run no boost at all.

All this stuff has been around for the best part of a century and real automotive engineers have decided when to utilise what on production vehicles. And I think they in most cases thes engineers were able to complete their most successful designs without a single reference to wheels magazine.

[M14A-Mclaren]

Originally Posted by Steffo

Anti-Lag Systems (ALS) basically allow unburnt fuel to enter the exhaust tubing, where it explodes due to the high exhaust temperature.. and those explosions keep the turbo spinning.. allowing you to run insanely high boost at idle..

http://www.rallycars.com/Cars/bangbang.html

Good article there.

They obvouisly don't always work, I saw on Top Gear they put an Evo 8 FQ400 and floored it, against some Fiat Stilo Estate and the Fiat bet it down their runway becuase the turbo lag was so bad.

My understanding is that turbo's can take more space as well, thats why no one has been able to turbo a Boss powered Falcon, is that about right?

[dansedgli]

Originally Posted by M14A-Mclaren

My understanding is that turbo's can take more space as well, thats why no one has been able to turbo a Boss powered Falcon, is that about right?

APS have done a twin turbo Boss.

[Mike Gayner]

Steffo you are living on an absolute fantasy world.