Turbocharge or supercharge?

[ChrisBrand]

I know this has been a question on alot of peoples minds and i know that the two systems work on different rev ranges. The turbo on high revs and the supercharger on low. So i would take it that personal preference plays a role here. After installing a chip in my e46 328 im thinking of maybe fitting it with a turbo but only set at like 0.5 bar. Which of these two would not damage my engine too much and which is more reliable. Thanx alot guys

 

[Clownshoe]

Supercharger give a more linear power delivery, so you maintain the driverbility. Turbos tend to be peaky and have a lag (turbo lag). That is why BMW went the twin tiny turbos because there is less lag.

Supercharger is a pump that runs off the cranck, turbo is an impellar that runs off exhaust gasses that drives a propellar that compresses air for the inlet.

The reasons I think turbos are more popular is they are cheaper, you can get more boost out of them, easier to install and they are lighter.

I would only go with a supercharger. With a supercharger you can have a clutch installed so its power on demand otherwise you have it all the time.

 

[Hellas]

Remember Mad Max? (Well, one of them...)

 

[Clownshoe]

This one?:dropjaw:

 

[Hellas]

imp: yeah...

All I remember from that movie was the manual clutch he engaged to get the supercharger spinning :excited:

 

[///Marksman]

a centrifual blower only makes peak power at high rpm with a very linear delivery as clown said, actually so does a twinscrew with the latter much beefier down low.

however, going with twins or even a smaller turbo will yeild much more low end torque than a blower. Imho lag only becomes a real pain in the ass when chasing big boost/HP numbers. It all comes down to your driving style and preference really. and with the turbo, you could always turn the boost up notch when feeling stupid and switch it right back when feeling civilised which may be rare...

 

[STREETRACER]

I know this has been a question on alot of peoples minds and i know that the two systems work on different rev ranges. The turbo on high revs and the supercharger on low. So i would take it that personal preference plays a role here. After installing a chip in my e46 328 im thinking of maybe fitting it with a turbo but only set at like 0.5 bar. Which of these two would not damage my engine too much and which is more reliable. Thanx alot guys

Bud Charger has ups and downs! Charger comes in smooth, charger doest have lag etc.. But a charger boost the whole time if you cruize on the highway at 3000rpm it boosts the whole time! dus you should give more fuel to accomodate for boost and makes it heavier on petrol!

Turbo cars only boost when its under load!

When you turbo a car and you use the correct exhaust housing not to big and a decent size compressor housing you will boost from 3000rpm - 7500 rpm! you can also flip in a boost controler to manage boost through out the range to come in smoother! So with technology today ill go for turbo! The 328i is a square motor 84mm bore 84mm stroke! which make it a dream to turbo! Do it right and expect 600hp out that engine!

If you have turbo lag your exhaust housing is too big!

I dont care who says what i will not turbo your car on stock compression! not even 0.5bar!

Also expect to pay between R65k and R85k for a decent job! Expensive cars to brake if not done properly!

Your clutch will not hold up either! plus with turbo car you cant accelerate for long distances like cruize 200km/h for 50km!
Bud the gains you'll get on 0.5 we just got N/A with out opening the engine! Read my thread on my brothers 325i with M52 328 engine!
We made 144kw and 249nm that is 1kw short off a stock 3.2 M3 and 10kw more than a 3.0l M3..

You want chip, TNT exhaust, TNT branch, BMC filter and M50 Manifold! Which is way cheaper than a turbo conversion anyway! and much more reliable! I will post the dyno graph tomorow!

 

[Major]

If you have turbo lag your exhaust housing is too big!

I'm sure you mean 'too high of a boost threshold' than 'turbo lag'.

with turbo car you cant accelerate for long distances like cruize 200km/h for 50km!

Why not?

Bud the gains you'll get on 0.5 we just got N/A with out opening the engine! Read my thread on my brothers 325i with M52 328 engine!
We made 144kw and 249nm that is 1kw short off a stock 3.2 M3 and 10kw more than a 3.0l M3..

Have you seen a dyno graph for a stock M52B28 boosting 0.5bar (7 psi)?

 

[STREETRACER]

@Major

Ive seen a M52B25 boosting 0.5 and it made 147kw.. stock it made 92kw!

Take any aftermarket car and gun it over 50kms your turbo and exhaust housing runs to hot and i can see you getting towed home! Factory turbo is another story!

Bud do you know how many turbo cars ive sorted with boost lag to big! and all of them i changed to a smaller exhaust housing!

 

[P1000]

@Major
Take any aftermarket car and gun it over 50kms your turbo and exhaust housing runs to hot and i can see you getting towed home! Factory turbo is another story!

Then you were probably underfuelling. There is no reason for an aftermarket turbo to be less reliable than factory if done properly. Under boost you should be running rich (afr of 11.5-12.5max) in order to cool everything down, especially the exhaust manifold and turbo. But getting enough fuel in means bigger injectors and new software/ECU.

 

[STREETRACER]

Bud Tuning wise i can teach! But please tell anyone with a aftermarket turbo on his car i will race him with a stock N/A car of his choise from pretoria to bronkhorstspruit and back!

 

[Major]

Ive seen a M52B25 boosting 0.5 and it made 147kw.. stock it made 92kw!

And a B28?

Take any aftermarket car and gun it over 50kms your turbo and exhaust housing runs to hot and i can see you getting towed home! Factory turbo is another story!

If you design it poorly, yes, and as P1000 said, tuning plays as much part in thermal control as the actual design of the parts involved.

You've also changed your statement from "cruise at 200km/h for 50km" to "gunning it for 50km". You can cruise at 200km/h for 50km and have as many problems as an N/A car. You don't need full throttle to cruise at that speed, your turbo would hardly ever step in.

Bud do you know how many turbo cars ive sorted with boost lag to big! and all of them i changed to a smaller exhaust housing!

Again, are you sure you're talking about lag and not boost threshold? Lag exists in every turbo system ever made, it can't be eliminated. It exists by design.

 

[STREETRACER]

Soz for the cruize at 200 that will be fine unless it runs under load!
Im very afrikaans so threshold is not in my vocabulary! thanks for windows spelling correction otherwise no one will know what the f*** im saying!

But i understand what you are saying but not even a SAV turbo will gunn for long extends!
I asume you have seen the heats a turbo manifold can get under load! how can that be safe than?

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[P1000]

I'm not debating whether the average guy that slaps a turbo on his car has an IQ of 10 or 12, and will inevitably have a poor EM design/construction and be underfuelling. I am just debating theory. Why would a after marked car running the same CR, same displacement, same fuel ratio, same timing, same turbo, same EM and same boost be running a higher EGT than one that came from the factory?

I do agree with you in the general sense and that sticking a turbo on a car is not a trivial exercise, mostly done with all the corners cut, but with proper execution there is no reason why your EGT should be higher than in a factory turbo car.

I also agree that your solution by keeping the car N/A is very elegant and definitely more cost efficient and reliable...

 

[STREETRACER]

Even better example!


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[Hellas]

wow...mashmallows anyone?

 

[STREETRACER]

Bud i love turbo dont get me wrong but if you turbo do it properly! If your aim is for 0.5bar than Turbo is not what he is looking for! Our turbo E46 323i is making 258kw and 498nm and not a days shit! We drive it every where! I understand the concept but just wanted to help CHRISBRAND make the right choice for his car and needs!

 

[ChrisBrand]

Wow, thanx alot guys. The reason for the 0.5 bar was for safety of the engine. More boost puts more strain on the engine. Ive heard that the guys from SavSpeed could fit the turbo for not too much if set at 0.5 bar. But i think for now StreetRacer's proposition might work better in my case.

You want chip, TNT exhaust, TNT branch, BMC filter and M50 Manifold! Which is way cheaper than a turbo conversion anyway! and much more reliable! I will post the dyno graph tomorow!