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i'm not sure if this has already been covered, but always, i know that turbo replace your header, and s/c replace your intake manifold. But my question is, is it possible to run both turbo and s/c at the same time in your car???? if yes, how crazy will it be. if no, why not? thank you.

(no flaming)
 

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Well i dont know how it would work with an si, but it is possible, i have seen dual charged cars before.... The craziest one was when i was up at nopi this past year i saw a tiberon that had a turbo, s/c and nitrous... never seen such a thing.... I doubt it helped, but it theoretically is possible.
 

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wouldnt the turbo be running its set psi into the blower and the blower would still turn at its same speed driven by the engine rpm so no matter how much extra air u force in the blower would still only allow its own set psi into the engine?

cliff notes on the question: 8psi from turbo into 7psi blower ( pulley limited) = engine recieves 7psi so whats the point? or am i wrong.


or would it indeed work and basically you'd get the no lag off the line power of the charger and the top end power of the turbo once its spooling. but then again the turbos power has to go through the charger after its going so doesnt seem super efficient. bet its hot as hell. lol
 

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wouldnt the turbo be running its set psi into the blower and the blower would still turn at its same speed driven by the engine rpm so no matter how much extra air u force in the blower would still only allow its own set psi into the engine?

cliff notes on the question: 8psi from turbo into 7psi blower ( pulley limited) = engine recieves 7psi so whats the point? or am i wrong.


or would it indeed work and basically you'd get the no lag off the line power of the charger and the top end power of the turbo once its spooling. but then again the turbos power has to go through the charger after its going so doesnt seem super efficient. bet its hot as hell. lol
hmmm... i would think it would be additive...head-pressure. 15lbs into engine.
i'm just speculating though. that's how it is for water pressure and fire pumps. 60psi coming out of a hydrant and fire pump developing 100lbs of pressure yields 160psi at discharge.
 

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Turbo is good for hi power band and fuel economy at low band.
This is because there is no "loss" from using it.

S/C is parasitic, but boost is "instantaneous". So it's good for low-medium power band.

In order for both to work together, the boost "level" for each has to be the same. in a normal car.

It's possible to run them with eachother, but you cant have a 15psi s/c and then a 30psi turbo (in a regular car). This would create a "backpressure" on the supercharger and it would in essence turn into a BOV that doesnt turn off.

Generally speaking, not enough room in a normal car to do both. (Unless you have a big block engine compartment, but then put in a smaller engine displacement to add in your twin chargers)

There are disadvantages to this setup, mainly the supercharger drag and extra weight and volume of the additional components. This becomes a larger issue when used on small economy cars which lack space within their engine bays.
In dragsters they run huge superchargers to help spool turbos, 500hp parasitic to make ~3000hp, and that's so that the turbo's can spool up to speed. The turbos then spool to make another 8000hp. (not exact figures, but you get the picture)
 

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Detroit diesel does twin charging with their 13L V8 marine engine . It is an, I believe, a 92mm turbo with an eaton 8-71 blower boost reg'd at ~9.3psi. Total output is around 1300 lb.ft/tq and 700HP.

I believe that it just works on the principle of lowend grunt provided by the SC. After that the turbo spools and the blower compresses the already compressed air from the turbo increasing top end performance. Tuning the AFR and ignition for this set up would be tedious, but rewarding.

The volume of air provided by the turbocharger would be further compressed by the blower given its efficiency at higher RPMs etc. I would suspect this would also create a need for extreme intercooling.

To icewildabeast, I wouldn't suspect that a turbo pushing 30psi would cause an issue with a blower because the blower would pull the charge from the turbo because it is constantly pulling and compressing air. The pumping volume of the blower would be the only thing that would matter, or so I would assume. So wouldn't this scenerio be more relative to volume than pressure?

Very interesting brainstorm we got here.
 

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You could abosoutly do both efficently such as the newer VW's do. Engage the Supercharger until the Turbos bossts then have some sort of Clutch based Pulley on the Charger that disengages the charger and the engine runs on the Turbo alone.

I will have this one day ;)
 

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Turbo did a project MR2 that had a turbo and a SC. The SC covered the low end and got the HUGE turbo to spool up. They said that the turbo blew so much air that is was actually spining the SC so fast that the SC pulley was puting power back into the engine. Then it went kaboom i think.

This is the way most engines of the future will be. Small displacement, DFI, VVT of all types, Twincharged with hybrid drive trains.
 

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Turbo did a project MR2 that had a turbo and a SC. The SC covered the low end and got the HUGE turbo to spool up. They said that the turbo blew so much air that is was actually spining the SC so fast that the SC pulley was puting power back into the engine. Then it went kaboom i think.

This is the way most engines of the future will be. Small displacement, DFI, VVT of all types, Twincharged with hybrid drive trains.
This is why a clutch on the charger is needed and some sort of valve on the charger side of the throttle body. This can be done on the Si because of the way turbo's and supercharge mount on engine.
 
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