Forced induction questions

[Kender]

A couple of questions

1) Does anyone know why most (if not all) of the pictures of turbo'd 4age engines on the net use the n/a intake manifold as opposed to the s/c or custom intake manifold?

2) What is the advantage of turboing the 4age as opposed to using a centrifugal supercharger?

Cheers
kender

[Monsterbishi]

A couple of questions
1) Does anyone know why most (if not all) of the pictures of turbo'd 4age engines on the net use the n/a intake manifold as opposed to the s/c or custom intake manifold?
2) What is the advantage of turboing the 4age as opposed to using a centrifugal supercharger?
Cheers
kender

With a Turbo'd car, you have much more room to play with on the inlet side, allowing for a better flowing manifold, ie a NA one.

Turbo's reign supreme because of their lower parasitic mass, means that as engine rpm's rise there's not nearly as much power being sapped, It's also easier to get a larger turbo with much more flow than it is a supercharger.

[Mr Revhead]

ahh but he said centrifugal supercharger, which are far better than the 4agze type, a lot of the same things apply but a centrifugal one would be an interesting prospect if a suitable one could be found, their main advantage is a far less parsitic drag. they also eliminate the inlet manifold choice problem. and they can flow heaps! but as i said the challenge would be finding one of a suitable size, maybe vortech to something

[Monsterbishi]

ahh but he said centrifugal supercharger, which are far better than the 4agze type, a lot of the same things apply but a centrifugal one would be an interesting prospect if a suitable one could be found, their main advantage is a far less parsitic drag. they also eliminate the inlet manifold choice problem. and they can flow heaps! but as i said the challenge would be finding one of a suitable size, maybe vortech to something

Good point, only downside to a centifugal blower is the price :-)

[Mr Revhead]

yes it wouldnt be cheap as i dont think theres anything out there that would have a suitable blower you could find 2nd hand.... but id would definitly be interesting project, one id be into myself if i had the $$

[mike simmonds]

neither supercharger or turbo are better than the other, they are just better at different things, if its throttle response and toque ur after obviously the supercharger would be the better option, but if u want top end and higher horse power ud go for the turbo as they are more efficent at producing top end power, they do resrict the exhaust but they dont drain 20%+ power like a supercharger does. just hav to weigh it up i guess.

[Kender]

Thanks for that guys.

I've started thinking/daydreaming about a future upgrade for my race car. I REALLY like the instant throttle response of a super charger, and I've watched a lot of race cars struggle with turbo lag around the corners at Ruapuna, so I'm quite interested in seeing what can be done with a supercharger. I'm prepared to sacrifice outright (peaky) hp if the extra torque (and broader powerband) means that I can get better drive out of corners.

Now I just have to figure out how to make a centrifugal s/c with some tin foil, chewing gum and a rubber chicken. Does anyone know Macgyver's phone number?

Cheers
kender

[Chickenman]

021 108 3500

[badidas]

CAN ANYONE SAY SUPECHARGEDTURBO
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2.0L TURBO, 4 WHEEL DRIVE with a 600+BHP 3SGTE ENGINE
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[Andy from the block]

, if its throttle response and toque ur after obviously the supercharger would be the better option, but if u want top end and higher horse power ud go for the turbo as they are more efficent at producing top end power,

If turbo are more efficient at producing top-end power , how come the fastest drag cars in the world (ie the 8000hp dragsters in US) use supercharged engines, not turbo ones?

[EVLGTZ]

, if its throttle response and toque ur after obviously the supercharger would be the better option, but if u want top end and higher horse power ud go for the turbo as they are more efficent at producing top end power,

If turbo are more efficient at producing top-end power , how come the fastest drag cars in the world (ie the 8000hp dragsters in US) use supercharged engines, not turbo ones?

err because drag racing is not all about top end power its about getting off the line and over the first 400m as quick as you can. Torque is the key here....

[Lanius]

And lets not forget that those drag cars have to rebuild the engines after every run

Some of the facts about those "cars" (monsters?) would amaaaaaze you

[Mr Revhead]

different horses for different courses... i think kender could have an interesting idea there, definitly not a waste of time looking further into it i reckon. drivability can quite often beat outright horsepower...

[spencer]

, if its throttle response and toque ur after obviously the supercharger would be the better option, but if u want top end and higher horse power ud go for the turbo as they are more efficent at producing top end power,

If turbo are more efficient at producing top-end power , how come the fastest drag cars in the world (ie the 8000hp dragsters in US) use supercharged engines, not turbo ones?

You cant bring those cars into the equation the are 500 cubic inch nitromethane beasts (which are more like 6000hp or less) which can spare abit of hp to spin that blower on a 4age or similar a turbo robs less power. Fastest FWD and skylines etc use turbos you cant compare them to top fuel

[Lanius]

Centrifugal superchargers ... are they the s/chargers that are based on an archimedes screw type of design?

I was told those are the best as they produce constant flow instead of in pulses as produced by the roots type on the GZE's.

[Mr Revhead]

they are basicly half a turbo, instead of the exhaust driving them they have a pulley and belt in place of the exhaust wheel. thats what makes them quite good for certian applications.
they are HUGE in the state on the mustangs, also chev and ford fit them stock to some models

[92GTApex]

Now I just have to figure out how to make a centrifugal s/c with some tin foil, chewing gum and a rubber chicken. Does anyone know Macgyver's phone number?

It is possible to modify a turbo, removing exhaust wheel/housing and driving it directly from the engine, thus making a centrifugal supercharger.
But this wouldnt be as good as a purpose designed/built centrifugal supercharger like a vortech or similar

Logan

[Mr Revhead]

in theory yes..... not sure how it would work though, turbos are designed to work at very high revs as are centrifugal s/c, the superchargers run a gearbox to get the requierd compressor speed so youd need to do that which isnt impossible but could make for an interesting time!

[92GTApex]

Yes they are made to operate at very different rpm levels, but it can me made to work.
I think centrifugal superchargers are around the 50,000rpm mark compare to turbos at around 150,000rpm (very rough figures, to show example)

Logan

[fivebob]

If turbo are more efficient at producing top-end power , how come the fastest drag cars in the world (ie the 8000hp dragsters in US) use supercharged engines, not turbo ones?

Because the rules mandate the use of that specific type of blower, along with 2 valve engines, mechanical fuel injection and fixed diff ratios. If they allowed more modern technologies they would be a lot faster and a lot more dangerous.

While top fuel dragsters are the most powerful I/C engines, they are definitely not the most efficient.