Supercharger install

Glad to hear that it works for you now, it will be nice to have a look at your installation, and hear how it sounds.

Zitat von huldra66;74959

I have tried his car and it's really brutal now , torque on low rpm is just amazing.
I have a CSI myself but do not think I have any chance to keep up in the acceleration

We have to try one day

Regards
Terje

I should have thought the S/C 850 would easily blow the Csi away as I know my old S/C 840 would eat a stock Csi

Zitat von Noggie;74950

I have now driven the car for 2 days and she runs pretty well.
The mix is a bit on the rich side but there is plenty of power.
I will do a dyno on Monday and we will see just how much power there is.
Expecting something like 370-380whp and (490nm) 360ft-lbs of wheel torque.

Hi Noggie,

did you go to dyno the new DME setup yet?

cheers
firebird

I'm Very curious what the dyno will say Egil, hopefully the car will be behaving himself now and fall apart again(I know the problem).

Tomorrow we start to install a new S/C into my car(now only one, not two) and we must make the preparations, the next weeks we will put the charger on(and we can compare the Dyno results....)

Hope that it will be a success for you!

With the other chargers I had mix so 17/18L-100K, by 80K so 8L-100K, on the Highway so 20/23L 100K.
Than your consumption is high, yes, but I think it's better for the engine when it get more fuel than really needed so it can cool better(but that is to much).

350 BHP is not to bad, you loose quiet a bit by the charger himself.
(perhaps 50/60 BHP?)
My other chargers were on the dyno 362 BHP, but the run wasn't completed because there was a drop of presssure and this was for the second run 0,2 bar extra.
It should be 450-460 what had to be expected.
By the second run there was another drop of pressure and we came at 340 BHP, also the pressure was than 0,2 bar.
Everytime one of the hoseclamps was gone, unlucky we couldn't fix it without taking the chargers away and than it hadn't any use to go one because the seals wouldn't be dry in time.
To bad we never had a real messurement, but as the y say bij RR: "it was sufficent" driving with it.

When you get the 350 at first result it really isn't to bad, some finetuning and you should get much more...

Hi Noggie,

here's my two cents on the matter...: Camshafts for naturally aspirated engines and camshafts for turbo/supercharged engines are not the same thing, at all.

With higher valve overlap (what your cams probably offer), you might experience an effect called "scavenging". That would help with low-end power significantly more than what you'd expect (after all, you should expect a loss in low-end power in a naturally aspirated engine). With too much overlap or "wrong" speeds you might just as well experience a loss in power at higher rpms.

Without that effect, tho' (and the cams need to be designed for that effect) more aggressive cams will not increase power nearly as much with a turbo/supercharged engine as you'd expect from the naturally aspirated setup. If you get 10% from your cams normally, you might get 5% in a boost setup.

No matter what it is: You need an individual chip tuning. One, that takes place at the test bench and is done at all rpms, all gas-pedal positions and all temperatures look-up points given in the map of the chip. All of this needs to be done individually for your car. Something like that, done right, will take about at least 2-3 days! (a car manufacturer spends about half a year for that, by the way).

All of this sending info back and forth to and from the USA is more likely to kill your engine than give you a good setup.

But, again, that's just my opinion... and I guess that you don't have a choice...

Zitat von fuzzifikation;75767

Hi Noggie,

No matter what it is: You need an individual chip tuning. One, that takes place at the test bench and is done at all rpms, all gas-pedal positions and all temperatures look-up points given in the map of the chip. All of this needs to be done individually for your car. Something like that, done right, will take about at least 2-3 days! (a car manufacturer spends about half a year for that, by the way).

All of this sending info back and forth to and from the USA is more likely to kill your engine than give you a good setup.

But, again, that's just my opinion... and I guess that you don't have a choice...

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That is a true point Dieter, it can only be correct when the car will be on a dyno, chips being modified, than driving, again modifing, a.s.o.
It takes normally a day or more.
When you planned a inbetween trip to NL Egil, our clubtuner is a very good writer that will programm your engine very good.
Costs are between 700 and 1000 Euro, but than you are sure that the engine is ok.
He will programm my engine again when the new charger is on it, I can't use thamn the chips that are already tuned(only to drive to him, not more).
It is essential to enjoy the charger, otherwise it's only a big pain in the as....

Egil,

here's some thoughts on fuel consumption:
20L/100km is not only ok, but quite good. Here's how to look at it:

Your supercharger takes approx (as a wild guess) 70HP from the engine to compress the air. Yes, I am not kidding, here. In lower RPMs, maybe, it's just using 20HP. Well,

So: the supercharger, alone, uses about as much power than a normal driving scenario without the supercharger (normal driving should be a lot less than 100 Engine HP most of the time).

So you see: Adding a supercharger will NEVER help with fuel consumption. It's quite the worst thing to do. A turbocharger is a lot better in this respect as it uses the exhaust gas engergie (which is otherwise wasted, anyway) to drive the compressor.

In essence: A supercharger is something you add to the engine to gain power at the expense of fuel consumption. On the plus side, however, that power come without lag.

Zitat von fuzzifikation;76074

Egil,

here's some thoughts on fuel consumption:
20L/100km is not only ok, but quite good. Here's how to look at it:

In essence: A supercharger is something you add to the engine to gain power at the expense of fuel consumption. On the plus side, however, that power come without lag.

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Hmm

The Old superchaged 840 of mine went from averaging 22 mpg to 26 mpg after the S/C Maybe I should have kept it

I asked many people in ;the trade about my cars new found ecconomy & was told it was not un heard off to see a supercharged car gain better economy?

Sorry this is no use to you Egil do hope it gets sorted soon.

Zitat von stevep840;76075

Hmm
The Old superchaged 840 of mine went from averaging 22 mpg to 26 mpg after the S/C Maybe I should have kept it

I asked many people in ;the trade about my cars new found ecconomy & was told it was not un heard off to see a supercharged car gain better economy?

Sorry this is no use to you Egil do hope it gets sorted soon.

I agree, it's no use to Egil, but interesting nontheless, isn't it?

Charging an engine can - if done right - increase the combustion efficiency. In essence what charging does is raise the compression ratio (at least it can somewhat be interpreted as such - yes, yes: it's not correct, but the interpretation is valid.).

SO: "compressed and cold air good for engine."

BUT: All of this comes at quite a higher cost: Namely the power necessary for the supercharger. As an example: In the McLaren SLR, the engine produces something over 620 HP. The supercharger, alone, however, needs 160 HP !!. This means that at max. power, the engine actually delivers 780HP - of which 160 go to the supercharger.

Well.. the 160HP aren't generated for free. It requires fuel to do that!

The same goes for any supercharged engine. As a rule of thumb, one can state that a supercharer needs approx 1/3 of the net. engine power for the supercharger. All this power needs to come from the fuel..

So: A supercharged engine needs - in general - more fuel than a naturally aspirated one. (Note that this statement does not hold for turbocharged engines).

How can you still save fuel? Quite easily: Drive it slowly! With more power in the low end, you can drive around at - say - 1300 RPM instead of 2000 RPM. What you save in friction losses there is quite significant!

As another rule of thumb: in a modern engine (not our old shitty stuff), friction losses are about as high as the actual usable power output. So, if your car measures 200HP at the testbench - another 200HP are gone for friction losses! This is the reason why all car manufacturers look at reducing friction. An friction goes up proportionally with engine speed!

So: Use lower engine speeds ==> Save a lot of fuel! And with a supercharger that is possible without having to drive slow! (good stuff)
However, once you drive faster -> your fuel consumption will go up, significantly!

Sorry guys, you are all on the wrong track. The supercharger will draw almost no power until it starts to boost. You are all mistaking this for a positive displacement supercharger and you have got it all wrong...

The centrifugal supercharger will improve fuel consumption until you use any extra power it produces over standard. This is because it makes the engine more efficient.

It was stated above that you will have "more power in the low end, you can drive around at - say - 1300 RPM instead of 2000 RPM". Why is that? You will not have any boost and a far less efficient intake!

"The same goes for any supercharged engine". Afraid not, only with a positive displacement supercharger such as a Rootes type blower.

"All of these have seen better consumption at cruise". Yes, this is because at a cruise speed, the supercharger can be blowing into the manifold yet not producing boost, so the engine will have zero pumping losses as the pistons do not need to draw in the mixture.

"that power come without lag". I am afraid not. The supercharger will have almost identical lag to a turbo although it will be purely rev related and not rev and throttle position related like a turbo.

"No matter what it is: You need an individual chip tuning. One, that takes place at the test bench and is done at all rpms, all gas-pedal positions and all temperatures look-up points given in the map of the chip. All of this needs to be done individually for your car. Something like that, done right, will take about at least 2-3 days!" Absolutely correct.

Your cams will make a slight difference to the tuning of the engine but not much. There is no room to increase the lift with any significance, and if the duration was particularly high, it would have driven awful as standard at low revs which it didn't. Forget the cams, they are really not the problem.

"as long as I'm not ending up with a result that will damage the engine I'm happy." Thats not sounding hopeful I must say. At that rate, and with 308 bhp and poor fuel consumption you may as well go back to standard!

Sorry guys, I kept out of this as long as possible.

8Tech.

PS, Parcel on its way Egil.

Zitat von Noggie;76071

Before this it is slightly above the previous map, and the A/F mix is a little better, but still lean.
This I do not understand as the consumption is really bad, at cruise it's 14.5L/100km, and at mixed daily driving I'm well above 20l/100km, I find this strange if the mix is lean.

Egil,

that's because your dyno is taken in full throttle what means you are in the VL maps (full throttle for fuel & timing).

your "bad" consumption is actually representing the TL maps (partial throttle).

I assume you measured AFR at exhaust pipe during all your dynos.
For optimum process AFR needs to get measured before catalytic converter.

I would recommend you to install an AFR meter on permanent basis anyway in your car. I bed it will show way to rich when you are using TL maps.

Did you ever get an accurate chart of your boost over rpm?

firebird

Zitat von 8Tech;76150

Sorry guys, I kept out of this as long as possible.

One thing about lag - if I may

Turbo Lag is the time a turbocharged engine takes to produce significant power at a fixed engine speed. So there are different lag times at different engine speeds.

but.. there is one other thing:

Turbo Threshold is the minimal engine speed at which a turbocharged engine starts to produce significant boost (independent of how long it takes it to do that .. the time would be its lag at that speed).

So:... A supercharger (and especially this turbo compressor which, obviously has been put in this engine - forgot about that) has threshold similar to a turbocharger as it will not produce significant boost at very low rpms...

However it will still produce more boost at low rpms than a turbo which has been chosen to produce the same driving characteristics. That is because it does not have a turbine which simply worsens the overall efficiency and will not run as well down there..

With the other stuff.. I'm afraid that Gerry does have a point. A turbo compressor will draw little power from the engine if it's not actually compressing air a lot.

But: If it starts to compress air even a little, its power consumption is quite bad. This is, because it will operate at very low efficiency until it reaches a higher speed and high compression ratios.

And then there's one more thing... if a supercharged makes an engine more efficient (which it does to the compustion efficiency) - it does this only by adding boost to the intake manifold. Which needs power.

Finally: A turbocharger is wildly more efficient than a supercharger considering overal fuel economy!

Why? Because with a turbo, the control unit (nowadays they're pressure controlled by electronics) will simply open the wastegate if power is not needed. Then, the turbo will not produce high boost, whereas the supercharger always does.
Worse so: If the driver doesn't need the boost deliverd by the supercharger (he steps off the gas pedal) then the throttle plate will need to eliminate (= waste) all the precious boost that was created by the supercharger (at high cost!).

Note that when I'm comparing turbo vs. supercharged, I don't mean those turbocharger approaches with fixed boost - these are only ok if you want to race your 8er all the time - it's just bullsh... for everyday driving.

A supercharged approach is always better than a turbocharged approach that is done wrong (fixed boost).

Gerry.. your turn