If I wanted to run a very small amount of boost, say 5 psi at most on a car, and since it's such small amount of boost, use a small, fast spooling turbo and only put it on one side of the v6 motor, what would happen? Anyone done this?

 

saab does that.

 

left wheel spins faster then right wheel?

 

Saab doesn't run turbo V6's, IIRC.

Most of the Saab's are 4 cylinder turbos.

I can't imagine it would be good to run one bank of 3 cyls on the turbo, and one bank of cylinders n/a.

Aside from the fact that on a 3L V6, running a small turbo on 1 bank is pushing 1.5L displacement through the turbo....in order to spool that up quick, it'd have to be a turbo so small you'd probably not gain any power from running it at such low boost anyways.

 

I beg to differ. I have a saab motor here that I am re-building that came out of a 1999 nine five, and its a V6 six with a single small turbo running off one bank of 3 cylinders. I can take pictures of it if you don't believe me.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chimmike &raquo;</TD></TR><TR><TD CLASS="quote">Saab doesn't run turbo V6's, IIRC.

Most of the Saab's are 4 cylinder turbos.

I can't imagine it would be good to run one bank of 3 cyls on the turbo, and one bank of cylinders n/a.

Aside from the fact that on a 3L V6, running a small turbo on 1 bank is pushing 1.5L displacement through the turbo....in order to spool that up quick, it'd have to be a turbo so small you'd probably not gain any power from running it at such low boost anyways.</TD></TR></TABLE>

Saab has turbo v6's. they currently use a smaller displacementt version of GM's high feature v6 and it is turbocharged.

 

It works very well on the saab. THey have a pretty sophisticated fuel delivery system for it, though. Hell, even their old trionic was a big pain in the suck.

Ian

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by x SPY x &raquo;</TD></TR><TR><TD CLASS="quote">I beg to differ. I have a saab motor here that I am re-building that came out of a 1999 nine five, and its a V6 six with a single small turbo running off one bank of 3 cylinders. I can take pictures of it if you don't believe me.


</TD></TR></TABLE>

I would love some pictures just to see how they did it.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chimmike &raquo;</TD></TR><TR><TD CLASS="quote">

I can't imagine it would be good to run one bank of 3 cyls on the turbo, and one bank of cylinders n/a.

</TD></TR></TABLE>

just because the exhaust spooling the thing comes from one bank does not make the other bank naturally aspirated.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by danielm3 &raquo;</TD></TR><TR><TD CLASS="quote">If I wanted to run a very small amount of boost, say 5 psi at most on a car, and since it's such small amount of boost, use a small, fast spooling turbo and only put it on one side of the v6 motor, what would happen? Anyone done this? </TD></TR></TABLE>

I believe the Buick Grand National's turbo is fed from only one bank, and it certainly does not have any problems making horsepower.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ginsu2k &raquo;</TD></TR><TR><TD CLASS="quote">

I believe the Buick Grand National's turbo is fed from only one bank, and it certainly does not have any problems making horsepower. </TD></TR></TABLE>

they dont have a Y-pipe?

 

type in "saab v6 turbo" in google and look at images. plenty of pics of it.

i've done single turbo v6 before. you just need to make a crossover pipe that leads to the up pipe. pretty easy. just make sure to put a flex in between manifolds, it will help with your fitment after you weld.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Mr.E.G. &raquo;</TD></TR><TR><TD CLASS="quote">

just because the exhaust spooling the thing comes from one bank does not make the other bank naturally aspirated.</TD></TR></TABLE>

if what he's saying is true, and there's no y pipe directing flow of all 6 cylinders into the turbo, then only 3 cylinders worth of exhaust gases are feeding the turbo, while the other 3 are essentially dumped into the exhaust stream separate from the turbo and "wasted"

No, the GN wasn't fed only off 3 cylinders.

Turbonetics' 350z single turbo kit is a perfect example of running a single turbo on a V6 and utilizing all 6 cylinders via a y pipe.

 

running only 3 cylinders would probably not be the best idea. you would have some crazy difference between the two banks as far as fuel and timing.

it would be pretty interesting to see it work.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by manifoldmiketyson &raquo;</TD></TR><TR><TD CLASS="quote">running only 3 cylinders would probably not be the best idea. you would have some crazy difference between the two banks as far as fuel and timing.

it would be pretty interesting to see it work.</TD></TR></TABLE>

How would the timing and fuel be affected? The engine should (unless I don't know something) work the same, boost would go in and exit... maybe just faster on one side than the other. The engine would still be on 6 cylinders; just 3 would be powering the turbo instead of 6. I see it as maybe being not efficient, but I can't think of why it wouldn't work... the only thing is the o2 sensors since it may be a different one bank being turbo and the other not.

 

hehe, people don't realize that 3 cylinders will be pushing the turbo but all 6 will be getting pressure from it. with an intake manifold that feeds the whole engine.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by chimmike &raquo;</TD></TR><TR><TD CLASS="quote">

if what he's saying is true, and there's no y pipe directing flow of all 6 cylinders into the turbo, then only 3 cylinders worth of exhaust gases are feeding the turbo, while the other 3 are essentially dumped into the exhaust stream separate from the turbo and "wasted"

</TD></TR></TABLE>

great. that still doesn't make it naturally aspirated. it still sucks down boost on the intake side.

a supercharger doesnt run off of any cylinder banks exhuast flow but that doesnt mean the engine is naturally aspirated.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by danielm3 &raquo;</TD></TR><TR><TD CLASS="quote">
How would the timing and fuel be affected? The engine should (unless I don't know something) work the same, boost would go in and exit... maybe just faster on one side than the other. The engine would still be on 6 cylinders; just 3 would be powering the turbo instead of 6. I see it as maybe being not efficient, but I can't think of why it wouldn't work... the only thing is the o2 sensors since it may be a different one bank being turbo and the other not.</TD></TR></TABLE>

more heat and pressure in some cylinders is going to affect the tune. if you were running a pressure ratio less the 1:1, there probably wouldn't be too much of a problem.

either way, its a pretty retarded idea. you would want all the cylinders pushing that turbo you could.

i'm not saying it wouldn't work, nor would it work well, but i'll garuntee running all runners to the turbo will promote power, spool and an easy tune; therefore making it better.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by manifoldmiketyson &raquo;</TD></TR><TR><TD CLASS="quote">

either way, its a pretty retarded idea. you would want all the cylinders pushing that turbo you could.

i'm not saying it wouldn't work, nor would it work well, but i'll garuntee running all runners to the turbo will promote power, spool and an easy tune; therefore making it better.</TD></TR></TABLE>

this is why I can't figure out why Saab would do this.

I googled "saab turbo v6" and nowhere could I find a picture depicting the turbo specifically only being run off one bank of cylinders. Just makes no sense that they'd do that.

I don't doubt now that they make a turbo v6, but that's not what I'm debating.

 

They did do it.

Only reason I could think to do this would be lack of room in your engine bay. In that case I'd personally look into running a remote mounted turbo.

EDIT: Just found out why they did...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">The new Saab 9-5 is the first car in the world to be equipped with an asymmetric turbocharging system. This new engine concept uses the Saab 3.0L V6 engine equipped with one turbocharger mounted on the front cylinder bank, driven by exhaust gases from only those three cylinders. The single highly-responsive Garrett GT17 turbocharger delivers compressed air to all six cylinders in both cylinder banks. Combined with a boost pressure which reaches only 3.6 psi (0.25 bar), this technology allows a patented boost control system via the throttle control which eliminates the need for a wastegate. The turbocharger housing is integrated into the exhaust manifold instead of being a separate casting, for even greater efficiencies. </TD></TR></TABLE>
http://forums.tdiclub.com/showthread.php?t=22347

And the big reason is:
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">The asymmetric turbosystem increases peak torque by 15%--to 229 lb-ft at 2,100 rpm--improving useful performance and reducing passing times. The higher torque also allows longer gearing, which improves fuel economy and reduces emissions.

For higher torque at low engine speeds, the engine's Light Pressure Turbocharger uses relatively low boost pressures to deliver boost quickly.</TD></TR></TABLE>
http://www.designnews.com/article/CA126482.html


Modified by BlueCrxNC at 8:38 PM 7/1/2008

 

I've worked with plenty of Saab tuning systems before; they do adjust fuel individually and on the single turbo v6 setup they run different timing maps on each bank and use compression response knock sensing.

Ian

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlueCrxNC &raquo;</TD></TR><TR><TD CLASS="quote">

http://www.designnews.com/article/CA126482.html


Modified by BlueCrxNC at 8:38 PM 7/1/2008</TD></TR></TABLE>

okay, it increases torque by 15%.....over a the non-turbo 2.8L V6? It just seems incredibly wasteful to me to not use a slightly larger turbo and both banks of cylinders to get probably 30% more power at the same efficiency?

Or, they could've just used a larger displacement V6 which could/would be just as efficient, and gotten the same power figures. I.E. VQ35DE style power.

It just seems like they seriously overcomplicated the entire management system rather than adding a single exhaust pipe from the other bank of cylinders to the turbo and increase the exhaust piping size slightly.

 

I wonder if they still use this single turbo / single bank design? If not, I'd say that they realized what you said was better. I happen to agree with you. I was just sharing the information I found.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by BlueCrxNC &raquo;</TD></TR><TR><TD CLASS="quote">I wonder if they still use this single turbo / single bank design? If not, I'd say that they realized what you said was better. I happen to agree with you. I was just sharing the information I found.</TD></TR></TABLE>

the pics I found said there's a turbo v6 in the 2008 saab turbo x....I think that was the model.

Either way, like you said, remote turbo would be good for aftermarket purposes, or small twins. Shoot, the turbonetics kit is able to fit a 60-1 in the vq35 engine bay with all the associated piping. It's a REALLY tight fit........but man, it makes power!

 

tbi was a great idea too at one point.

heres some pics of a single g35 i did a while ago. maybe this might help. for some reason i can't find any pics of the finished product from the engine bay though.