Turbo Vs Super charger

[Jess walter]

on a vx whitch one is better and a myth about super charger that it sucks the fule down true or fulse

[dynoryder]

fulse


turbos are better

but to a lot of missconception super charges are pretty good but you want over the top screw type

centrafugal ones are uneficent and put stess on the crank

[dynoryder]

supers can be overdriven by changeing the spools

[Jess walter]

Thankyou Mate My friend said just to get a new computer chip to make is faster and louder ?

[dynoryder]

not louder need exaust for louder

[Jess walter]

cool thanks alot for the info :-)

[chargedvx6]

Roots or twin screw supercharger for 0-80km'h (street) or turbo for unbeatable top end and turbo rush. Just leave centrifugal charger out of the equation

[dynoryder]

turbos can give low down take off just need small ones

[danja]

Just leave centrifugal charger out of the equation

And why would you do that?

[dynoryder]

And why would you do that?

and if you read one of my posts up a bit more it tells you

[Adriianz]

supercharger for short drags, turbocharger for long drags. if you want quatermile, go turbo, if you want street use and hooning, go supercharger. supercharger works the seconbd you put the foot down, turbos' dont kick in untill 2500 rpm. hope that helps.

[dynoryder]

no you can get turbos to work from idle they just dont give you top end

tractor pulling events have guys with 4 turbos 1 small 2 bigger 3 even bigger and so on

some turbos can make boost at idle

real twin turbos should have a big turbo going into a small turbo so you get takeoff and topend

or you could go turbo fed supercharger

but turbos can be setup to your needs

[Tsunamix]

Ok let me dispel some myths here.

Superchargers by design are actually more effecient that turbo chargers.

Turbo chargers have a huge heat pool close to the intake system, and uses a vaned compressor that does not seal on the compression side. The heat causes air expansion and the lack of seal means compression is based on massive rpm.

Super chargers (roots type) have a sealing vane, which means you get more efficient compression per rotation. This means RPM's are low, frictional losses due to rotational speeds are lower, but frictional inefficency due to vane / housing contact is higher. Roots blowers are hard to intercool because there shaped often dictates placemeent between the cylinder heads.

Screw type superchargers Also have a sealing rotor, giving higher compression efficiencies. The downside on these is there compression stroke (# of rotations to compress one charge) is quite high so rotational speeds tend to be higher, so do frictional losses. Again - intercooling is hard.

Centrifugal superchargers used a seal less compressor that is almost identical to a turbocharger compressor, needing high rpm to function effectively - exactly as per a turbo charger. This is provided by a gearbox, driven off the crankshaft snout, by a belt drive. Unlike a turbo, there is no massive heat pool from the exhaust so Compression is more efficient as the air is cooler. Additionaly, Centriifigal superchargers can have there jackets water cooled (which turbos cannot) to remove even more heat at the compression point. This means extended life due to cooler running bearings over turbos. because centrifugal types are usually remote mounted, intercooling is often easier that screw and roots type superchargers.

The down side to centrifugal superchargers is that compressor speed only rises as engine speed rises. This usually means less boost at lower revs. The answer to this is to use a smaller pulley drive to build compressor speed sooner, and a blow off valve to bleed excess boost at higher rpm.

In terms of overall efficiency - centrifugal superchargers rate mid range for compressor efficiency (same as turbo chargers), equal highest for intercooling (same as turbochargers), and highest for cooling and longevity (with roots, screw and turbo behind it in that order).

They are not often used on production vehicles as the remote mount can be very difficult to package. But because of there cooling running design, engines that do use centrifugal superchargers, do not need to run a lower compression ratio, unlike roots and screw type superchargers.

[danja]

and if you read one of my posts up a bit more it tells you

I read your posts. I was not impressed, you don't seem to know what you're talking about.

Thankfully Tsunamix has summed it up pretty well, and much more accurately.

[dynoryder]

to spool up a cent superchager then let the psi out with a blow off valve is unefficient

the only point you make over turbos is they have a heat pool near them but that is overcomed by engineering mate

hmmm lets see maby for the last 30years ppl have been bringing the heat down

but on the other hand the superchargers on top fule darg cars are the best for power they have been proved

but not evry one has $1000000

so turbos still the best for a vx mate there are kits on ebay for $5000 now that is bang for your buck

[Tsunamix]

Can buy a centrifugal from Raptor for $5000 too, and theres comes with warranty, tune, oversize injectors and instructions, and is locally made to boot.

Superchargers have been around since before WW2, and were used on the spitfire engine in 1942. So superchargers have had there technology worked on for at least 60 years, and probably more.

There has been no change to heat dissaptaion in turbo chargers since inception. The heat collector (impeller in the exhaust) is still positioned at the ocmpressor in the intake stream, seperated by a whole lot of metal.

Blow of valves work by letting out EXCESS pressure not all pressure - exactly the same as on a turbocharger, so saying they are inefficient on a supercharger, also makes them inefficient on a turbocharger.

[dynoryder]

turbos spin faster and dont back off with the engine right away so you need a blowoff to help the turbine slow for that spit second

as for cent charges yes they same price but man they are shiit they are the worst sort of forced air

srry those pezzy little elec fans for your intake are the worst

[stocky]

I read your posts. I was not impressed, you don't seem to know what you're talking about.

Thankfully Tsunamix has summed it up pretty well, and much more accurately.

i agree with him. centrifugal chargers are useless compared to a turbo

[VN_Luke]

i agree with him. centrifugal chargers are useless compared to a turbo

and I agree with him. ^^

centrifical charger would be good for an application where rpm is pretty constant - i.e. a WW2 plane, or a boat, or something like that. - it is in this scenario where a centrifical charger would be better than a turbo.

In a car, this type of charger is able to pull a nice peak power dyno figure, but "real world, on road" performance, where RPM (and as a result, boost level) is constantly changing, is generally lacking. (in my opinion)

[Tsunamix]

My comments were about efficiency of design, not about suitability to a specific application.

they all have there pros and cons, all have similair cost, all have applications where they excel.

Generally speaking, ALL superchargers (not just centrifugal) build boost along with RPM, simply because they are ALL mechanically driven from the crankshaft snout.

Turbochargers build boost in line with exhaust gas speed, which is also relative to engine RPM. All have a trade off between Boost and RPM. Smaller turbos produce boost sooner, but pump smaller volumes of air. Twin turbos do not automatically answer the question, as in that scenario exhaust gas pulses are split between the 2 turbochargers (excepting the more complex twin in line systems and the like - Think mazda RX-7). SUperchargers suffer from the same 'indexing' to RPM, and there are partial solutions for those as well.

In real world terms, The biggest advantage shown by any system, for purley street use, is the lack of heat and greater mounting options presented by centrifugals. It requires least modification and customisation, and has comparable (if not greater) thermal effeciency. Turbos can be wound up to a greater boost level, and the sacrifice of lag. But then superchargers can run smaller pulleys for greater boost as well, without lag.

The moral of the story is - If you want torque, superchargers are good value for street and strip. If you want ultimate power, turbos can provide more boost that a supercharger with greater ease.

Horses for courses. Pick your favourite.

[danja]

They've all got pro's and con's, I'm just trying to figure out why you'd simply dismiss one of them out of hand? Nothing I read in the first 10 posts explains why you would.

[nick3110]

Okay this is a little bit off topic, but it'll stop the forum bitch fight lol...

Is it possible to install a turbo or a supercharger (either kind) to a dual fuel system?

I have my theories but I'm not 100% sure on the matter.

[Tsunamix]

It is possible, but it would be complex.

LPG and ULP burn a little differently. Actually LFG responds to Forced induction very well - probably better than ULP.

At first glance you would need to seperate tunes, 1 for each fuel, or a very conservative one that covers both, which will to an extent, defeat the purpose.

[dynoryder]

yes but lpg injection with forced air is better than dual fule

[dynoryder]

i still want to see some one in streetmachine with an liquid lpg injection foced air v8 makeing over 1000hp