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  • 11/22/2011
Does anyone on here have any experience with sizing superchargers? I am throwing around the idea of supercharging the Talon once the motor is back in now that I have a dummy block to test mounts out on.
  • 11/22/2011
I know that kauffjd3 does for sure... he has like 4 supercharged mustangs, lol. Now if only the @ function worked, ha
  • 11/23/2011
Originally posted by ROCKYSDS
Now if only the @ function worked, ha
Haha, work in progress!
  • 11/23/2011
Well, I guess I will let the cat out of the bag a little bit here. I am looking to twincharge my Talon once I get her back together. At first I will go with just the supercharger to work out all of the kinks that comes with custom fitting a supercharger on. I can understand that using too small of a charger will force it to overrev and take it out of its efficiency zone and just generally pump hot air. My question is, what are the drawbacks to installing a supercharger that is oversized for the engine? I imagine that there are more parasitic losses on a larger supercharger. How much? Is there a "lag" associated with a larger one? I took the 4 chargers by Eaton and placed my 2.0 liter engine on there at approximately 10psi. The reason I am asking this is because I want to play with turbo placement with the supercharger. Heck, even putting the turbo first actually changes the pressure ratio the supercharger runs at. Running a supercharger at 10psi in 14.7psi atmosphere is about 1.7PR, when you feed that supercharger from a turbo putting out 20psi the PR drops to 1.3. Anyways.... back on subject.... What I want to play with is having a supercharger feed the turbocharger. I know how the boost curves work in my head. Let me see if I can get them out in excel graph form for everyone to understand before I explain it more.
  • 11/25/2011
Ok, prepare for theory and graph overload! Ok, all of these curves that I made are based off of a 2.0L engine (4G63) and my 20G engine boost response. I assumed about ten thousand variables just to get a close idea of the concept, because without about 5 bachelors and masters degrees I dont think that we could properly account for all of them! The below picture is what I imagine the boost response of a typical compounded twincharged system (where the air goes through the turbo, then the supercharger and then to the engine):What I would like to do is play with changing the order of the chargers in order to increase the boost response and low end torque. The boost response would look similar to this graph (A much flatter torque curve):A quick little side note: The reason that the psi of the supercharger in this situation drops off when the turbo begins to come online is because that the supercharger operates via positive displacement whereas a turbo operates via the centrifugal principal. Meaning that a supercharger will suck, compress and blow out a fixed displacement per revolution and a turbo depends slamming air molecules into the charge pipe using centrifigual force, which isnt linear with RPM. Basically the turbo increases the displacement of the engine that the supercharger sees (At a PR of 2, the 2.0 L engine is acting like a 4.0 L to the SC). So, based on wanting a total of 30 PSIG from the engine I ran some quick calculations on the pressure ratios and volume flow of each scenario throughout the engine RPMs:And then transposed these to the efficiency curves of the M90 and M112:So, I guess on to my main question, when the supercharger is first in line before the turbo spools up the pressure ratio of the supercharger is way off the charts. For a couple thousand RPMs would this be acceptable and not pump way way too much heat into the engine? Extrapolating the efficiency curves it looks like it will be around the 45% efficiency. Anyone have any thoughts or questions about this?
  • 12/7/2011
Eagle Talon? why not just turbocharge it? more kits available, much easier to install, adjust boost. and less money spent down the road on upgrades.
BW S366 on Emanage Ultimate and 1260cc, walbro 450lb, E85
  • 12/7/2011
Originally posted by -defi-
Eagle Talon? why not just turbocharge it? more kits available, much easier to install, adjust boost. and less money spent down the road on upgrades.
I believe he's working on twin-charging....
  • 12/7/2011
Originally posted by -defi-
Eagle Talon? why not just turbocharge it? more kits available, much easier to install, adjust boost. and less money spent down the road on upgrades.
It already is turbocharged. I am talking about twincharging it in order to get better boost response and a more square torque curve. Basically it will not only give me better off boost response (because with a positive displacement supercharger you are never off boost), but it also would spool up a turbo the size of your T61 about as fast as the stock T25 on my engine.
  • 12/7/2011
??? what kind of horse power are you looking for? if you want more response and power just save yourself the hassel, get a t4 DBB turbo with a divided housing, a manifold with an (UNDIVDED) HOUSING and install a QSV. super chargers take power to make power.
BW S366 on Emanage Ultimate and 1260cc, walbro 450lb, E85
  • 12/7/2011
Originally posted by -defi-
??? what kind of horse power are you looking for? if you want more response and power just save yourself the hassel, get a t4 DBB turbo with a divided housing, a manifold with an (UNDIVDED) HOUSING and install a QSV. super chargers take power to make power.
End goal I am aiming for "daily drivable" 600+ HP from my 2.0L. The GT3788R will spool up just shy of 6,000rpms on my engine. How well does the quick spool valve work for you guys? From the dyno charts they show it looks like it only offers about 300-500rpm savings on spool, which is awesome, but not enough for what I want. At best with just that turbo and QSV I would be getting full boost at 5500 RPM. I am aiming for full boost closer to 4000rpm and anything lower would be a bonus. I am not building the car for drag, but more for track days and daily driving where peak HP numbers dont mean anything, it is the broad powerband that counts. That is true. So do turbochargers through the backpressure the turbine creates. Turbos just dont have that mechanical link to the crank that superchargers do.
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