Supercharger or Turbo system is the question

[ICE90]

I've been lookin to add a supercharger or turbo charger to my car but when i got to shops they tell me that its a hell of a lotta work to turbocharge a M3 because it is a high compression engine and has to be converted to low compression............ they gave me the option of supercharging it... And now i can't decide does anyone know the pros and cons of both?

[Apex E36]

What year is the M3?

[Scho]

AA makes a Stg1 kit that retins stock compression. 400bhp too.

[cartooner_1337]

First you must understand how a turbo's and supercharger's work. Superchargers are belt drivin from right off the engine so you dont need to wait for the turbine to spool up which means that you get boost all the time. On the other hand having any thing run off of your engine will rob it of small amounts of horsepower (AC, heater, supercharger, etc.). Now turbo's are run off of the exhaust comeing out of the car so the amount of boost that you get is directly related to the revs of the engine. Because of the way a turbo works you get this thing called "turbo lag" when you shift up because the engine drops its revs and the turbo stops spooling so you need to wait for it to spool up again which means a small period of little to no boost. All in all the choice is up to you, you can get a little more power from a turbo but its not as consistent as a supercharger.

[///AlpinePower]

Go with the Turbo. I watched the Discovery Channel Special on Jet engines and Turbos put SCs to shame.

[M-freak]

if your car is OBDII it should have forged internals, which will make it easier to do a turbo set up. mine is OBDI so i am in the process of changing over to forged parts. in my case, i believe that a turbo setup is better because m3s already have enough torque off the line, a supercharger will be too much torque straight off. a turbo will be a good balance between the m3's low end torque and a turbos higher end. you can find plenty of places with forged parts for either the 3.0 or 3.2 if your interested at all, i can send you a list of sites i am using for mine.

plus the sound of that turbo spooling up, then the blow-off valve going.... it just makes you happy in the pants compared to what a supercharger does. the only problem is the price tag for a turbo setup might not make you quiet as happy (i found supercharger for around $3500, turbo runs around 7,000)

[jderry]

I thought all of the cranks for the S50 and S52 are forged?

[BMWGuy206]

The S50 crankshaft is cast. The S52 crankshaft is forged. Both connection rods are forged. Both the pistons are cast.

[jderry]

Both connection rods are forged. Both the pistons are cast.

Is this for both the S52 and S50 or only the S52 Jon?

[BMWGuy206]

Both the S50 and S52 engines have forged rods. Pistons are cast.

[esp1976]

If it's a daily driver I would gor supercharger. if it's a toy go turbo

[M3-4-Life310]

if your gonna do it once and spend that much money on either a SC or a turbo just go all out man and get the Turbo... that is if you have the funds... just going off gains... Turbo kicks SC's ass

click

AA TURBO

check it out!

[x3n0-SDT]

If you do go with turbo then I would suggest buying a blow off valve which helps get rid of some turbo lag, plus it sounds bad-ass too.

[Billj747]

It depends on your preference. Turbochargers are like driving a 2-stroke, not too much down low, but mid-range and top end pull is a lot of fun. On the other hand, superchargers are more practical. Personally I like turbos more but I dont know enough about the BMW's motors to know how they handle either. It seems that most people go the superchager route with their BMW's.

[RAiMA]

Really comes down to personal preference and application. Both methods are good ways of producing power.

Altho turbos are quite popular, superchargers can also produce some decent power. The car I'm driving at the moment is a detuned (CF) supercharged 318ti at produces 248RWHP from the 1.9L M44 engine. The supercharger was mainly chosen because they're generally smoother to drive than the single turbo counter part. With the car being circuit driven this year, this is important to maximise traction while exiting corners.

BTW, superchargers do use BOVs, as they run all the time and need to vent the excess air when the throttle is closed.