call it a stupid question if you will.... would installing a turbo charger make my supercharger useless/ineffective?

 

A SuperCharger and a TurboCharger both do the same thing. They're Blowers. The SuperCharger runs off a belt. The Turbo runs off exhaust. You don't need both if you have one or the other.

There's only so much Boost you can tolerate. Over-boosting won't (shouldn't) happen because after so much Boost you relieve the Boost Pressure through a Waste Gate.

If you are looking for a reason to spend some money that's burning a big hole in you pocket ... put it toward goodies that will compliment your SuperCharger. Perhaps a nice new PowerTrain Control Module would make you feel more horsies!

 

If you get one of the run of the mill turbo kits for the 3800, you would be removing the rotors from your supercharger, and putting in a block-off plate where the snout would be. Go to Cartuning.ca to see what I'm talking about.

If you have lots of money to burn, and really want to twin charge, contact zzperformance. They've done it on one of their cars. Low end boost from the SC to get the car going, then the turbo takes over, and the SC goes into by-pass mode to allow the turbo to flow well. Complicated setup, good gains, expensive.

 

Partially correct. Our Eaton M90 supercharger is considered a "blower", because all it does is blow air air, creating a positive pressure in the manifold. Twin screw SCs, CSC (centrifugal), and other types of superchargers can be considered "compressors", because they "compress" the air before it exits theunit. In a turbocharger, the air is compressed before it goes out the turbo, so it's considered a "compressor".

Hope that clarifies.

 

I believe compressed air is cooler (correct me if I'm wrong) so the car runs better. VW has twin-charged vehicles before or are in the process of...Like Lav said, the SC is for low RPM's and the TC for mid-high RPM's...That is the advantage and disadvantage ofa TC....it has more power throughout the power band, but it kicks in at a middle RPM range...if you twin charge, you reduce or eliminate turbo lag. It is expensive though. Ford (On their 6.4L Diesel) and BMW (On their Inline 6 cyl)are using small electronic turbos to spool at idle and low rpms for instant boost as well as help spool the larger turbo before it kicks in at a higher RPM.

UPDATE:
I was wrong. Compressed air is warmer. Hence having intercoolers.

 

It has been done before on the 3800- I'd imagine there are probably 4 or 5 cars running around with both right now.

The idea is that you take advatange of the instant boost and instant torque of the supercharger- and use that to help spool a larger turbo.

Thats the bad thing about wanting to run a big turbo to make a lot of boost- turbo 'lag' can become very noticeable. The idea of dual charging is to eliminate that.

Personally- I'd rather just run a little 50 or 75 shot of nitrous to help spool times, but thats just me- both accomplish the same goal.


Yeah- compressing anything makes it hotter.

I think we're getting this thread a little tangled up on words though- even with a roots blower- air is still compressed. It is just compressed in the intake manifold because the blower is moving too much air for the engine to digest- and the backup of air creates boost. Its not much different than what a turbo does- its just a turbo isn't 'positive displacement' meaning with a supercharger it moves x amount of air from the inlet to the outlet each turn- whereas a turbo needs to really get spinning pretty fast to begin moving air at all due to the relatively large wall clearance- but air still compresses in the intake system due to the excess air being forced into the intake that the engine can't process.

What I think you're trying to get at is that the efficiency of a turbo is higher than that of a roots supercharger. A roots blower tends to add more heat to the air at the same boost level than a turbo does (especially when you start getting into higher boost levels).

 

the main issue of twin charging is cost vs gain. there are very few cases where a vehical would benifit from having both. it is cheeper to install and intercooler and drop pulley size then to add a turbo to an existing SC'd motor. same as adding a SC to a Turbo car.

further more, another issue with SC's (roots blowers like the M90) is that there is very little space for an intercooler. there is space after a turbo for a nice intercooler but the more you compress air the greater the temp increase... this is where "adiabatic efficency" comes in... long story short on that... each has a peak region where it is most efficent step out of that sweet spot and your using much much more power to gain very little or none.

the idea of turbo and supercharging is a very good one... more over it is actually the principal behind Jet engines.... combustion turns the turbine/exhaust blades...which inturn turn the Compressor blades on the intake to feed the burner/combustion section... and the pattern repeats.

heck with the continuous variable tranys that are out there now ... its time for someone to make a turbine powered car! spool the jet to an efficent RPM and then use the trany to adjust speed. prob could use the PCM to have max cruse and max power rpms.... for diff driving.