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KarateBoy
01-27-2004, 05:33 PM
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Recently i have been having an arguement with a few people if you can put both a twin turbo and a super charger.Can you?
What percent boost is it for a supercharger at reasonable (is it affected by RPM)? on a twin turbo (at ideal RPM)?
Will the HP be increased by the a percentage from the original HP or the new HP after the Supercharger or TwinTurbo?
What measure do you have to take so that your new engine can handle all this?
A cooling system is needed i presume but does it also increase HP?
Would a SuperCharger and a TwinTurbo contradict each other?
I also understand this is different from Car to Car let let us assume that is my beloved "M5" (natually aspirated with 400HP) I appreaciate the help.

Matra et Alpine
01-27-2004, 06:20 PM
Recently i have been having an arguement with a few people if you can put both a twin turbo and a super charger.Can you?
What percent boost is it for a supercharger at reasonable (is it affected by RPM)? on a twin turbo (at ideal RPM)?
Will the HP be increased by the a percentage from the original HP or the new HP after the Supercharger or TwinTurbo?
What measure do you have to take so that your new engine can handle all this?
A cooling system is needed i presume but does it also increase HP?
Would a SuperCharger and a TwinTurbo contradict each other?
I also understand this is different from Car to Car let let us assume that is my beloved "M5" (natually aspirated with 400HP) I appreaciate the help.
OK.
First, other than street bragging, there's no reason to put a Turbo and Supercharger in the same engine.
Each is capable of increasing boost and compressing Fuel/air mixture beyond what the cylinders and pistons can handle.
So, go for a supercharger to avoid lag or an expensive twin turbo setup.
Superchargers are easier to plumb 'from scratch' as turbos need to go in the optimum plkace in the exhauist pipes.
If you're going to play 'chicken' with boost then go for a programmable engine management unit with boost management included.
This will ensure you dont' exceed your maximum and give you a 'short burst' peak boost. Helps delay the moment of engine destruction :-)
Don't know the weaknesses in the M5 engine, someone else will need to get you particulars.
BUT, you'll need to look at forged pistons, conrods and billet crankshafts if you're wanting to push the limits. Of course, that means that it splits the block when you over-boost :(
Cylinder head strength would need analysis if you want to get extreme.
Camshaft, cam followers and valves also need uprating ( you're trying to control closure of the inlet valve and later open the exhaust valve at close to peak pressure in the cylinder !! )

So, how much money do you have ?
I think you could easily support a 10-15 psi boost in a bwm, butr that's based on past experience of the marque and nothnig specific.
If you want to just stick with the standard engine, the easiest thing to do is seek out a car already boosted and copy it. it will save you a lot of blown engines, warped heads and bent conrods. ( been there, got the T-shirt - not with Beemers tho' )

Matra et Alpine
01-27-2004, 06:53 PM
If you want to just stick with the standard engine, the easiest thing to do is seek out a car already boosted and copy it. it will save you a lot of blown engines, warped heads and bent conrods. ( been there, got the T-shirt - not with Beemers tho' )
New I had seen a shoot-out with a turbo and a super-charged M5.

Check out this link, it might help....
http://www.europeancarweb.com/features/0308ec_bmwbattle/index.html

KarateBoy
01-27-2004, 09:41 PM
OK.
First, other than street bragging, there's no reason to put a Turbo and Supercharger in the same engine.
Each is capable of increasing boost and compressing Fuel/air mixture beyond what the cylinders and pistons can handle.
So, go for a supercharger to avoid lag or an expensive twin turbo setup.
Superchargers are easier to plumb 'from scratch' as turbos need to go in the optimum plkace in the exhauist pipes.
If you're going to play 'chicken' with boost then go for a programmable engine management unit with boost management included.
This will ensure you dont' exceed your maximum and give you a 'short burst' peak boost. Helps delay the moment of engine destruction :-)
Don't know the weaknesses in the M5 engine, someone else will need to get you particulars.
BUT, you'll need to look at forged pistons, conrods and billet crankshafts if you're wanting to push the limits. Of course, that means that it splits the block when you over-boost :(
Cylinder head strength would need analysis if you want to get extreme.
Camshaft, cam followers and valves also need uprating ( you're trying to control closure of the inlet valve and later open the exhaust valve at close to peak pressure in the cylinder !! )

So, how much money do you have ?
I think you could easily support a 10-15 psi boost in a bwm, butr that's based on past experience of the marque and nothnig specific.
If you want to just stick with the standard engine, the easiest thing to do is seek out a car already boosted and copy it. it will save you a lot of blown engines, warped heads and bent conrods. ( been there, got the T-shirt - not with Beemers tho' )

So if i understand correctly I can put both a twin turbo and a supercharger but my engine won't handle it and there goes all my money? Secondly when you say "If you're going to play 'chicken' with boost then go for a programmable engine management unit with boost management included" what exactly do you mean? Do you have an idea if Bimmer can handle a 20psi boost? Also i know that the SuperChargers usually say up to 20 psi and so forth but what can you do to make sure you get the higher end of the spectrum? Finally i have searched google and found a calculator that told me, with 20psi supercharger a cooling system (2-core) and running it on some High ocatane full (maybe with an octane booster) i can get a 100%+ increase in HP- therefore a Bimmer would have 800+ Hp, does this seem logical?

fpv_gtho
01-28-2004, 04:07 AM
800hp out of an M5 sounds achievable to me, but there are so many variables that its almost impossible to determine how much horsepower your going to get from a certain PSI. i know that theres a kit that with 11psi from a vortec supercharger and an intercooler that will double the power of an XR8. the vortec superchargers have proven themselves for much more than 11 psi as well but they operate differently to what most people consider a normal supercharger, which is the roots or screw type supercharger (vortec is centrifugal type). these types generall make about 11 psi max. you can get ones that produce more but they cost alot more and i'd say are alot harder to maintain and run.

to answer your original question though running both superchargers and turbo's would be getting the same effect as twin turbo or twin supercharged. the packaging wouldnt be as hard as superchargers usually are plaved in the vee of an engine and turbo's hang off the extractors

KarateBoy
01-28-2004, 03:04 PM
Have you heard of the 20psi supercharger that if you run it with an intercooler and on high octane gas it usually get get you more than 100% increase in HP?

Matra et Alpine
01-28-2004, 06:39 PM
So if i understand correctly I can put both a twin turbo and a supercharger but my engine won't handle it and there goes all my money?
it won't do anything. You'd be as well putting only ONE on of sufficient boost.
They don't add, if the unit cannot produce higher boost it will only leak pressure backwards.

Secondly when you say "If you're going to play 'chicken' with boost then go for a programmable engine management unit with boost management included" what exactly do you mean?
What I meant was that if you are going to push boost limits way high then go for a smart boost management wastegate and not a crude control system. Boost management makes sure you don't exceed your programmed boost through the rev range. NOTE: It won't stop you programming it for boost that wioll blow your engine up !!

Do you have an idea if Bimmer can handle a 20psi boost? Also i know that the SuperChargers usually say up to 20 psi and so forth but what can you do to make sure you get the higher end of the spectrum?
Don't know though Autowerk in Germany have certainly got those figures. How much boost you want to run is dependant on the strength of all of the engine components, how much YOU want to dial in up to the maximu the turbo/compressor can produce. NOTE: just because the turbo can produce 20psi doesn't mean an engine can cope or use it.

Finally i have searched google and found a calculator that told me, with 20psi supercharger a cooling system (2-core) and running it on some High ocatane full (maybe with an octane booster) i can get a 100%+ increase in HP- therefore a Bimmer would have 800+ Hp, does this seem logical?
Logical yes, practical NO.
The calculator is using the THEORY of fule/air combustion.
In practice, you have to probvide the power to compress the air, get the fuel/air mixture INTO the combusion chamber and handle the bang when it's ignited.
I doubt a stock BMW crank, pistons or head could handle 800nhp. But I could be wrong.
It certainly will have a GREATLY reduced life at those pressures and power.
It's worth remembering that the guys who get the maximum power out of engines usually have enough income to pay for custom parts, rebuilds and don't mind the occasional engine blowing up.
Friends Nissan 300ZX has been uprated and he is now running full boost management and getting 400bhp with water cooled intercoolers. It's been mapped on rollin groad and clocked at Crail 1/4 mile. BUT, he's on his third engine, gone through about 6 twin turbos and a handful of gearboxes. It's his only hobby.
Are you THAT committed to getting power ?
Do you have THAT much money ??
For more specific BMW, you could try Danibin or Autowerk. They've booth donw serious tuning on the M5.

KarateBoy
01-28-2004, 07:33 PM
it won't do anything. You'd be as well putting only ONE on of sufficient boost.
They don't add, if the unit cannot produce higher boost it will only leak pressure backwards..................

Thank you so much. I don't have that kind of money and of course you can assume that someone would put in a new crankshaft...pistons...etc. I'll check it out.

DodgeNitroBIRM
01-30-2004, 06:34 PM
Thank you so much. I don't have that kind of money and of course you can assume that someone would put in a new crankshaft...pistons...etc. I'll check it out.

This has been done before, but, the car was more for show than racing. It was following the 80's trend that nothing was too much and it was an old 80's Pontiac, but, I don't remember the model. Looked almost like a Chevette. It had two superchargers, twin turbos, and Nitrous Oxide and ran on Alcohol. Looked like it would be a handful to drive, however, the guy how owned it did make one pass in it. Don't know what it ran.

Matra et Alpine
01-30-2004, 06:49 PM
the 80's trend that nothing was too much
yep, a guy in the UK put a Rolls-Royce Merlin engine into a Ford Capri.
That's the engine that powered the Spitfire , Hurrican and the best of the P-51s as well as Lancaster Bommbers in WWII. A huge monster of an engine with awesome power output and best of all - fantastic sound :)

fpv_gtho
02-01-2004, 02:27 AM
someone done that with some 55 model american car over here. i dont think it was a chev but it was that basic body style

Matra et Alpine
02-01-2004, 04:44 AM
A huge monster of an engine with awesome power output and best of all - fantastic sound :)
Never heard a Merlin engine ? watch this clip with racing driver and presenter Alain De Cadenet (language!) http://alexisparkinn.com/photogallery/Videos/ohmygodSpitfire%20pass.wmv
A guy turned up at our local air show with a Merlin engine on a trailer and proceeded to run it up. With the stub exhausts that thing is LOUD. I'll try to find the vid if anyone's interested.

DasModell
02-01-2004, 07:58 AM
yep, a guy in the UK put a Rolls-Royce Merlin engine into a Ford Capri.
That's the engine that powered the Spitfire , Hurrican and the best of the P-51s as well as Lancaster Bommbers in WWII. A huge monster of an engine with awesome power output and best of all - fantastic sound :)

not to mention some tractor pulling machines :) :)

crisis
02-01-2004, 05:17 PM
Never heard a Merlin engine ? watch this clip with racing driver and presenter Alain De Cadenet (language!) http://alexisparkinn.com/photogallery/Videos/ohmygodSpitfire%20pass.wmv
A guy turned up at our local air show with a Merlin engine on a trailer and proceeded to run it up. With the stub exhausts that thing is LOUD. I'll try to find the vid if anyone's interested.
I saw a racing boat once with one. The sound of a Merlin engine is magnificent. This boat put up a rooster tail so high it hit the bridge it went under.

MrVette83
02-17-2004, 07:45 PM
I am A student at Nashville Auto-Diesel college in Nashville, TN and did not even realize until recently a turbocharger can technically be a supercharger. A blower of any sort is more or less an air pump until 7psi of boost, at this point it is technically considered a supercharger. So, more or less anything over 7psi. boost of air is a supercharger.

crisis
02-17-2004, 10:45 PM
I am A student at Nashville Auto-Diesel college in Nashville, TN and did not even realize until recently a turbocharger can technically be a supercharger. A blower of any sort is more or less an air pump until 7psi of boost, at this point it is technically considered a supercharger. So, more or less anything over 7psi. boost of air is a supercharger.
I thought they difference was that one is mechanically driven and one is exhaust driven. Apart from actual definitions its easier to discern between the two this way.

fpv_gtho
02-18-2004, 12:16 AM
ive seen somewhere that turbo's are really called Turbine-Superchargers

Matra et Alpine
02-18-2004, 02:25 AM
I am A student at Nashville Auto-Diesel college in Nashville, TN and did not even realize until recently a turbocharger can technically be a supercharger. A blower of any sort is more or less an air pump until 7psi of boost, at this point it is technically considered a supercharger. So, more or less anything over 7psi. boost of air is a supercharger.
I hope they're not teaching you that in class.
Hopefully it was some guy over lunch trying to impress the ladies :)
It's BS.
Good luck in the course.

TheOne
07-02-2004, 03:38 PM
tho kennebell superchargers (http://www.kennebell.net) are only for so many cars, they do make it out to 15 or so psi, and are twin-screw type. a safe amount of psi for some(if not most) cars is around 6-8 psi without any kind of changes to the bottom-end. i've only seen so many super & turbo charged cars, there's not much effect besides a few more psi. i've also seen twin centrifugal and twin roots type superchargers, but those aren't much talked about.

megotmea7
07-02-2004, 07:33 PM
I am A student at Nashville Auto-Diesel college in Nashville, TN and did not even realize until recently a turbocharger can technically be a supercharger. A blower of any sort is more or less an air pump until 7psi of boost, at this point it is technically considered a supercharger. So, more or less anything over 7psi. boost of air is a supercharger.
a friend of mine is in the airforce working on deisls and support trucks for his MOS and he was taught the same thing... i wouldnt dismiss it so readily unless you to have some education inthe subject also

pmurf125
07-21-2004, 01:20 PM
Hate to join in late but just had to join in. The 1984/5 Lancia S4 Group B rally car had bothe a supercharger and a turbo. The inlet manifold was such that at low RPM (therfore low turbo boost) the supercharger helped to increase power and at highe RPM the supercharger cut out and the turbo took over. this was done in an effort to increase low end power and also to minimise turbo lag and the "step" in the powerband when the turbo came onto boost. Some tuners(I've only seen tis on bike engines) now use the inlet (blower) side of a turbo and drive it from the crank so that it works as a supercharger.

megotmea7
07-24-2004, 01:53 AM
Some tuners(I've only seen tis on bike engines) now use the inlet (blower) side of a turbo and drive it from the crank so that it works as a supercharger.
your refering to a centrifugal supercharger, essentially it is just the compressor side of the turbo driven by a belt or chain. better for high rpm operation that comparable roots type superchargers. its not new, been around forever

kko
07-30-2004, 11:45 PM
I have an article of a GTO with a supercharged Merlin in it

:eek: :eek: :eek: :eek:

ill try and find the mag tommorow