variable capacity intercooler piping

[themadscientist]

I was BSing with a freind about turbo response today, response -vs- capacity and I suggested this as a way to maximize both as much as possible. Of course valvetrain setting, porting and turbo sizing are still the most crucial elements but I could see something like this being beneficial to a circuit car where getting power quicker and more linear could be an edge, on the street it would be silly.

First we assume the turbo setup is good for the size of the engine and that the intercooler and piping runs are as unrestrictive as they can be. Now a big turbo needs big piping to flow at at full boost but at the outset the spooling turbo needs to fill all the piping and intercooler core before we start seeing positive intake manifold pressure. The Intercooler is a constant, it's size is fixed and unchanging but what if the pipe tract could constantly adjust it's dimensions to suit the situation, become smaller in diameter at low boost allowing more air to be used to fill up the intercooler and start pressurizing the engine? Here is the scheme;

The pipe diameter must be large enough for maximum flow at full boost. The interior of the pipes on the straight runs are lined with a flexible high temperature membrane. This separates the charge air from the pressure gas. A nipple is mounted on the pipe to supply the gas, Nitrogen perhaps that is housed in a central gas cylinder with a floating piston. This allows the the cylinder's static pressure to be increased by adding air to the space above the piston, like a set of sportbike forks. This adustablity would be needed as the gas has to have enough pressure to inflate the membranes inside the pipes and thusly constrict the diameter. It would have to be fine tuned so that as boost pressure increases the gas is forced back into the cylinder with the least amount of resistance. This would mean the system once dialed in would be automatic requiring no input from the driver or some kind of solenoid. The piping would always be the right size at every boost pressure and response would be better. Taking it one step further mount a coil of tubing inside the cylinder carrying freon. Circulating through it would chill the gas and thusly refrigerate the inside of the intercooler piping. It's pretty wacky and kind of exotic but properly executed could offer a real advantage on the circuit. Don't ask where it came from, I don't know. My brain just randomly drops stuff like this fully formed. Enjoy:D

[Mr1der]

you're the mad scientist, get in the damn lab and work son!:D

[Cyberkreig]

I was thinking more along the lines of a 3" flat garden hose.. but i GUESS your scientific way could be good too.

[themadscientist]

It's just too involved for a street car, I wouldn't actually try it. I'll settle for getting my seven running

[Cold_Zero]

TMS,It is an interesting concept. I would think the system would add more weight than benifit. In order to reduce turbo lag, could you just shorten the intercooler piping like they do with TMIC?

[MainEvent212]

how about extra piping that re-routes the IC piping's "path" to make it longer, more power up top right? and have the crossover made by solenoids at a certain rpm after 3rd gear or so? the jump can be done mid shift right?

[Cold_Zero]

I like your concept. There would be no benifit in making the hoses longer. The benifit comes from the diameter (unless that is what you are talking about) to allow more air flow. You could have two sets of hoses with a bypass valve to let the bigger hoses flow more air, under high boost applications and then switch to a shorter route or smaller hose for low boost (high spool) applications.

Possibly run two sets of Intercoolers? Top mount for low boost applications and Front Mount for highboost applications?

[redrocket]

in theory wouldn't the gas be forced out as the turbo got to higher boost

so all you would need to do is keep the side out side of the tubing pressurized so that as pressure dropped off the gas would flow back into the pipes

[themadscientist]

you grasped the concept exactly Rocket, once setup to right static pressure the system would be automatic.

[redrocket]

and that would be alot less weight then adding a whole extra intercooling kit and like you said you could use some way to cool the gas to freeze or damn near freeze the pipes while the air was coming through

[Mr1der]

perhaps a thin, stretchy rubber or silicone that can stand up to high heat in a carbon fiber or aluminum gas charged tubing?

[themadscientist]

one thing I wonder about is the affects of the sleeve's changing shape at the beginning and ending of each pipe in the run. Taken together with any sharp bends or joints which would be raw pipe or hose the ensuing turbulence might negate a lot of the benefits.

[redrocket]

not if you use a tornado

[themadscientist]

True enough *gets out scissors and empty coke can, begins fashioning Tornado*:thinker

[Mr1der]

don't forget the bandaids!

[AREITU]

I don't think there would be enough benefit to running that kind of setup. Properly sized pipes, free flowing intercooler, good tuning, and a turbo matched to your engine characteristics should reduce lag enough to where one wouldn't notice.

[Tastyratz]

i think that this is a great idea on paper, and i applaude your concept. the problem is actually executing something like this. you would need something that can constantly flex, take the heat, and not break down fairly quickly. some sort of membrane like you said would need to be a rubber of sorts, but after bending as much as day to day driving would make, i would imagine tears would develop and something might come off. also you would need some sort of gas that would be safe to be in the intake stream if a break were to happen.

[nametakennow]

Whoa... this is twice as cool as it is completely unfeasible. I love the idea but I just don't see how you could keep a membrane that would be smooth enough when changing size and when all the way flat (full boost) to not cause the turbulence you mentioned. However... you could also apply this idea to the exhaust stream. Think, if you narrowed the exhaust stream you could get higher pressure and get the turbo spinning faster sooner, and thus reduce lag. If you put them both together you would have the world's least laggy turbocharged car. However, the same problem with the smoothness of the membrane to prevent turbulence exists... surely there is some way to make this work...

[AREITU]

...you could also apply this idea to the exhaust stream. Think, if you narrowed the exhaust stream you could get higher pressure and get the turbo spinning faster sooner, and thus reduce lag...

Ever heard of a variable vane turbo, or twin-scroll turbo? Basically they change turbine profiles or the angle the exhaust hits the turbine changes (from at an angle, to more direct) to reduce lag. Nothing beats lag like good tuning and size-matching a turbo to the application.

[redrocket]

mad you know you were talking about the bends and things in the piping well if you ran all the piping and then ran the lining inside that would be the best thing and you wouldn't have to worry about it crunching up at the bends or anything