Twin SUPERCHARGED g35
#181
09-15-2009, 12:58 PM
The problem I see with this is the vortech pushing air into the stillen. Unless you have the vortech pushing just the right amount of air it will be counter-active.
For the same reason that your radiator fans stop spinning electrically when you are going 30+ MPH on the road. The airflow coming in is actually slowed by having the fan on.
I fear that this is the problem. If you can limit the amount of boost the vortech is pushing (via pulley size) to not overwhelm the Stillen then I think you will have a good idea. The problem is the Stillen is smaller than the vortech so it minimizes the overall effectiveness. In theory, it would be better to have the smaller supercharger pushing into the larger, similar to what a jet engine does.
Either way, I'm excited about the thought and I hope it all turns out well. Tuning this is going to be a b!tch.
For the same reason that your radiator fans stop spinning electrically when you are going 30+ MPH on the road. The airflow coming in is actually slowed by having the fan on.
I fear that this is the problem. If you can limit the amount of boost the vortech is pushing (via pulley size) to not overwhelm the Stillen then I think you will have a good idea. The problem is the Stillen is smaller than the vortech so it minimizes the overall effectiveness. In theory, it would be better to have the smaller supercharger pushing into the larger, similar to what a jet engine does.
Either way, I'm excited about the thought and I hope it all turns out well. Tuning this is going to be a b!tch.
#182
09-15-2009, 01:16 PM
IMO don't ask a question then if you don't want the answers...
MOST of us (again, not all, but most) have insights to how the setup will work, when someone asks "how well will this work, what are your ideas" we give em, even if they're not what some may want to hear. We're not discouraging, and in fact, I'd love for it get worked out just to see, but in the end, why do all that work to not benefit enough?
Think of it this way, if someone on the forums asked it it would be a good idea to jump in front of traffic, most of us would discourage it knowing it's not worth while to do so... Same thing here. I don't see why you think we're all out to get him, We're just giving answers to questions asked.
#184
09-16-2009, 04:07 AM
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#185
09-16-2009, 04:58 AM
i thought of something that might be useful. granted im more into boats, i know of something that was done on them. a friend had a hatteras sport fish, with twin diesel TIB engines. they required a supercharger to push the air into the cylinders. to get more power, they found adding a turbo before the blower was somewhat useful, hence the T. next, they intercooled them, the i. the B stood for bypassed, and what they found that the setup (almost identical to what you have now, save it was a turbo) was the way to go. what they did was they had the equilivant of a blow off valve, that acted as a bypass of the roots blower. i wonder if something like that would work here? if you do the y-pipe idea, i think that the boost from the roots would just back up through the vortech and cause a major drain. but maybe take a pre-stillen bov and bypass it to post stillen, since the roots blower is positive displacement and will not allow any air to go backwards, and the extra boost will just build into the engine.
and i have a intrest in this project, ive toyed with the idea of a turbo and super, im curious how this will work though.
and i have a intrest in this project, ive toyed with the idea of a turbo and super, im curious how this will work though.
#186
09-16-2009, 08:13 AM
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My bad i havnt posted any vids im still not done completely
I sorta understand what you are talking about but my main question is are you talkin about the stock bov that is built in2 the stillen and just making it always open? My idea was just to have a machine shop up the road from me make some pipes and a flange and cuz a hole right next to the stillen on the drivers side so the would run in parallel just would have to move my throttle body up and maf up from where they sit. also i would cut a hole on the side of the sillen to mount a wastegate so i could reg. the boost
i thought of something that might be useful. granted im more into boats, i know of something that was done on them. a friend had a hatteras sport fish, with twin diesel TIB engines. they required a supercharger to push the air into the cylinders. to get more power, they found adding a turbo before the blower was somewhat useful, hence the T. next, they intercooled them, the i. the B stood for bypassed, and what they found that the setup (almost identical to what you have now, save it was a turbo) was the way to go. what they did was they had the equilivant of a blow off valve, that acted as a bypass of the roots blower. i wonder if something like that would work here? if you do the y-pipe idea, i think that the boost from the roots would just back up through the vortech and cause a major drain. but maybe take a pre-stillen bov and bypass it to post stillen, since the roots blower is positive displacement and will not allow any air to go backwards, and the extra boost will just build into the engine.
and i have a intrest in this project, ive toyed with the idea of a turbo and super, im curious how this will work though.
and i have a intrest in this project, ive toyed with the idea of a turbo and super, im curious how this will work though.
#187
09-16-2009, 08:14 AM
Should have the Vortech connected to a big *** basketball sized turbo and then connect it to the engine.
That would be amazing to see. And actually be functional.
That would be amazing to see. And actually be functional.
#188
09-16-2009, 08:16 AM
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This is functional just needs some tweeking i hate turbos there for ricers. If ever heard the wine on a roots blower youd understand. Plus i ant got the money for something like that haha
#189
09-16-2009, 11:57 AM
Ok I get what your saying, but the problem I see with that is at low rpm when the stillen is pumping, the pressure is going to flow out of the vortech. If you think about it, there's nothing stopping that pressure from backflowing. What I'm saying is have it set up like you do now, then add another bov in the feed line to the stillen. Have the output of that bov run into the output of the stillen. Or do the y pipe idea, but put some sort of backpressure flow stopping thing there
Like the insane whine on the Cobra.
#191
09-16-2009, 12:32 PM
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i guess thats where we differ. just cant stand the lag and the sound. i built a srt4 caliber with 404whp and hated driving it cuz how the turbo just kicks in at like 2500 rpm. i mean if i press the gass i want that shi% now damit. if i had the money id done a ls7 corvette motor swap or a nissan titan swap just alot more slam you in your seat power witha v8...least with a roots ill be in the same ball park
if i did a y pipe there would be a need for a check valve i mean it be the same as hooking up the vortech by itself. the bov idea would work but i would be afraid of the bov not flowing enough air into the bottom of the stillen and causing back flow there. im not running enough boost to create any problems as of now but i need to have a game plan for when i get to build the bottom end.
Ok I get what your saying, but the problem I see with that is at low rpm when the stillen is pumping, the pressure is going to flow out of the vortech. If you think about it, there's nothing stopping that pressure from backflowing. What I'm saying is have it set up like you do now, then add another bov in the feed line to the stillen. Have the output of that bov run into the output of the stillen. Or do the y pipe idea, but put some sort of backpressure flow stopping thing there
#192
09-16-2009, 01:58 PM
Did you install bigger injectors yet? If you did, thats probably the reason that you are running so rich.
#193
09-16-2009, 02:31 PM
New member and Mechanical engineer here. While this isn't necessarily the most simple and efficient way to make power, there is no reason it shouldn't work, and work in the way built now. At this point I see engine management as the only real roadblock.
Many people have been bringing up the fact the the stillen is only good to 7 psi or so, which is true, when its cold side is operating at atmospheric pressure. The full statement here is actually that the stillen is only good to make a pressure DIFFERENTIAL of 7 psi at atmospheric. It is creating an additional 7psi pressure, on top of the 14.6 that exist at sea level. As with any compressor, be it a turbo, a roots or a centrifugal supercharger, the pressure they create is always relative to the pressure on the intake side. You'll notice the effect of this on a supercharged car driving at high altitude, they make less pressure at the manifold because there is less at the intake.
So what would happen in practice is that the vortech will pressurize the middle intake tube to some nominal pressure, say 7 psi max. Once it reaches the stillen, it will be further pressurized by some amount. The evidence of this operation can be seen in virtually any twincharged car(turbo into roots blower) For examples look into hillclimb cars or the lancia delta group b rally car.
Are there better ways to make power, yes. Will this be easy to get accurate air measurements, no. Will the car make more boost than with one supercharger, yes in fact probably more than an unbuilt engine can handle safely.
Many people have been bringing up the fact the the stillen is only good to 7 psi or so, which is true, when its cold side is operating at atmospheric pressure. The full statement here is actually that the stillen is only good to make a pressure DIFFERENTIAL of 7 psi at atmospheric. It is creating an additional 7psi pressure, on top of the 14.6 that exist at sea level. As with any compressor, be it a turbo, a roots or a centrifugal supercharger, the pressure they create is always relative to the pressure on the intake side. You'll notice the effect of this on a supercharged car driving at high altitude, they make less pressure at the manifold because there is less at the intake.
So what would happen in practice is that the vortech will pressurize the middle intake tube to some nominal pressure, say 7 psi max. Once it reaches the stillen, it will be further pressurized by some amount. The evidence of this operation can be seen in virtually any twincharged car(turbo into roots blower) For examples look into hillclimb cars or the lancia delta group b rally car.
Are there better ways to make power, yes. Will this be easy to get accurate air measurements, no. Will the car make more boost than with one supercharger, yes in fact probably more than an unbuilt engine can handle safely.
Of course if the stillen can be made to make enough hp to max out the bottom end anyway, the vortech is a moot point but this is more about logicistics and theory.
I've also not read much if any discussion about engine management.
#195
09-16-2009, 03:43 PM
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http://gt-rr.com/gt-r/r35/power_ente...r_kit/pid/326#
Check into this. This kit adds two superchargers to the twin turbos on the new GTR.
Check into this. This kit adds two superchargers to the twin turbos on the new GTR.