Supercharge NA6 ?

[greenMachine]

I looked at this closely a while ago, when contemplating where/how to get my HP fix.

It seemed that ultimate HP is probably turbo territory (no power sapping belt?), but for real world big HP/high torque output, a modern supercharger probalby has the edge (and the sound effects ), especially if you use something like an MP62 Eaton or equivalent Whipple/Autorotor positive displacement blower.

Biggest drawback for the supercharger is charge temperature, necessitating intercooling at lower boost pressure than a turbo would require.

For dyno results check out the FM (Whipple aka 'ubercharger') and BR Performance (MP62) sites. Both sell superchargers and turbos - that probably says it all really

Now, when I win the lottery ...

[Woo]

Sorry for the delay getting back to you all, very hecktic day today. Must be something to do with 666

Well I found the 9psi Ubercharger dyno here
http://members.optushome.com.au/woo/MX5/uber_140kpa_m2.pdf
and converted the imperial to SI units.

Then I converted the tractive force of the blue cars dyno plot (below) to torque at the axle on the assumption that the ft/lbs that Uber show on their plot is corrected (ie. not tractive force)



Then I plotted both on common axis for comparison


And I have to admit that the torque curve sh!ts all over the turbo.

My only comment in defence of the Turbo is they are considerably cheaper, but I know what my next spare time project will be

Wòó

[Woo]

Holy crap is that torque line correct for the s/c? that is huge

mmmm, so much so I'd like to see an independant dyno. But using the figures that FM supply .... it is huge.

Worthy to note that these figures are both 1.8's running 9 psi. Apologies for sortof running off topic.

Wòó

[Russellb]

Pity cos superchargers have far better power delivery!

I beg to differ on that score.
Turbos are not as rev dependant as a supercharger and are capable of making much more power.

Wòó

No,it's the other way around.
A turbo need to wait for pressure (ie rev) to build up to drive the turbine,whereas supercharged dríven by the crank-shaft boost-up from idle.
In regards to power (turbo or super-charge),depend how much boost you motor can withstand the pressure (usually by lots of $$).

IMHO turbos make the power earlier. Convince me otherwise with dyno plots.

Cheers
Wòó

BTW you'll need at least 220+ HP atw

220+ HP ATW does quick conversion
HHMMM 164.2 KW


Anyway got the Battery in today (after going for a run this morning and stalling Her Had to get a flat tow back to work ) and took her for a bit of a run with the laptop to do some tuning. After about 15mins I noticed that there was this squeal under boost so back to work to check it out. The S/C belt had come loose so after about 15mins it was back out with the belt retensioned and do some data logging .
30 mins later and were back download all the info and were making 4PSI at 2500 and a total of 11 at 5500 (new motor so trying to keep the revs down for a while) .
The torque out of this little 1600 is Amazing will have to run this on the dyno this week. I just have too know

WOO this thing comes on boost the moment you open the throttle
ther is no time waiting for BOOST. unlike the turbo. were you have to wait for it to spool up

Cassey I can tell you that the toyota S/C can do the same thing you say a turbo on the sp can do But the S/C come on stronger and harder down low Remember getting beten by my white sprinter had 5PSI up it at 2500 before your turbo and even though about doing anything


some of the noise you hear in the sound clip is the compressed Air venting out the BOV the rest is SUPERCHARGE whine

[Russellb]

Just using the STD turbo set up. BOV and vac line to manifold
if you have alook in the photo from underneath you will see it, under the Alternator

[Casey]

Cassey I can tell you that the toyota S/C can do the same thing you say a turbo on the sp can do But the S/C come on stronger and harder down low Remember getting beten by my white sprinter had 5PSI up it at 2500 before your turbo and even though about doing anything

That one can't be let through to the keeper. As I remember, I waited at the lights to let you move off first, and then when I did finally move off I was deliberately holding the car back to keep behind you. I don't do the street dragging thing - unless its an ACTION bus

Hmm - I have no doubt the old man's s/c will be something special, but all the ones I've dríven to date, the centrifugal and the M45 and M62 positive displacement ones, have nothing like the instantanious response of the turbo at freeway speeds in top gear. Kick them down a gear or two and its another matter - but they all lack the low down turbo torque.

[Casey]

Turbos are famous for two things bulk HP high in the rev range

Wrong again. Turbos are the preferred choice for stationary motors (ship engines, etc) and earth moving equipment and interstate trucks. Never seen a belt supercharger on a CAT, always turbos. And guess what, none of these engines do large revs at all. One of the icebreakers I have been on only did 720rpm flat out from its two deck high straight 8 engine. Guess what - it was turbocharged (the turbo was as tall as me - about 6' in diameter).

In fact the turbo is ideally suited to low revs and suffers a bit when you have a large variation of rpm (ie a sportscar ). Nonetheless, the advantages must outweigh the disadvantages otherwise F1 would not have had turbos as the dominant powerplant up until the mid 80's, nor would the worlds fastest car (which makes enormous torque - 1200 odd Nm) be turbo charged.

[Russellb]

EACH TO THERE OWN my Old mans NA6 is supercharged and run perfect. It has 7psi at 2000 and a total of 12psi
no more turbo V supercharger
Dyno booked for next week

[Russellb]

oh yeah bloody heck , you would think there is sheep stations riding on this , go out get anything that makes ya car go fast and bolt it on , it doesn't matter what it is , just as long you are happy with it. Cripes you would think people had shares in turbo companies or sc companies or something .

Here Here

I looked at the turbo supercharer thing on my sprinter
Was just going to pump turbo boost into the S/C and see what happed

[Matty]

The highest specific powered engines on the planet are not Formula one, but Top Fuel dragsters which are now routinely making 8,500+Hp from eight litre engines. Where are all the four second turbo cars ? If acceleration is your thing, why are all the fastest drag race classes supercharged ?.

Top Fuel drag cars are supercharged because the rules say they have to be.

A turbocharger wetup will always be more efficient than a supercharger - with the possible exception of some very well designed centrifugal SCs. But then a turbo of the same design would still be more efficient...

[Casey]

turbocharged Formula one cars make 800Hp per litre

The highest specific powered engines on the planet are not Formula one, but Top Fuel dragsters which are now routinely making 8,500+Hp from eight litre engines.

BMW Brabham F1 cars were making 1420bhp in 1983 from their 4cyl 1.5l engines - a bit more then 800hp/l. In later years with boost restrictions they were still able to make about 1300bhp. With the rate of technological development in F1, combined with modern materials and most importantly modern engine management systems, the mind boggles to think what sort of (unrestricted) power a F1 turbo car would be making today.

I'm not putting belt superchargers down, just some of the misinformed prejudices put forth on this thread don't stand up to the facts. Such as turbos only work at high revs, twin turbo Subaru setups are any good , superchargers give full boost at all road speeds, etc.

Personally the sound of a belt supercharger sends shivers down my spine, and Russellb's setup is one of the best. But the ones I have dríven (all brand new and cost comparable with an all new turbo setup - not cobbled together setups using second hand bits) have left me a bit cold in the power delivery and responsiveness stakes.

[Russellb]

Cassy come and take the Batmobile for a run tomorrow this will blow your mind

[Casey]

Cassy come and take the Batmobile for a run tomorrow this will blow your mind

Hee hee - you read my mind. Plan for tomorrow is to ditch the push bike and drive the car to work, take my staff out to lunch, leave work before 6pm, and see you guys for a beer while we drool over the batmobile.

How's the beer fridge?

[Russellb]

Cassy come and take the Batmobile for a run tomorrow this will blow your mind

leave work before 6pm, and see you guys for a beer while we drool over the batmobile.

How's the beer fridge?

In alright condition could use some variety
Will have the batmobile ready to run with a better map tomorrow
and maybe more boost

[Casey]

Well - what a pussy cat to drive. So well tuned already - it exhibited no bad habbits, with the exception of becomming a bit cammy at idle when the fans turned on (quickly fixed with a few deft keystrokes) and it hasn't even been on the dyno yet.

Can't comment too much on the performance as the engine is still being run in and revs were restricted to 5000rpm so nowhere near full boost yet. It left sharply from a standstill and would easily rotate the rear tyres from idle (similar to an SP with 2000rpm dialed up) and then the power surge quickly tapered off. I'm sure more tuning will overcome that. We still surprised a new SS Commodore though (although I think he was momentarily stunned by all the wonderful noises).

Didn't have the snap of a turbo during in-gear acceleration, but I wasn't using full throttle percentages being mindful of not wanting to overload the 200km old engine.

This thing will be a rocket!!

Edit - loved the short shift on the 6 speed gearbox. Wil have to get my own now