Turbo system idea?

[Snaps]

Just came up with an idea yesterday about a turbo system, I might have the way a turbo works wrong, so this could be impossible, or not work.

I was thinking of basically having a normal turbo, spooled by the exhaust, pressuring the intake, but then have another (N/A) intake coming off of the intake piping, with some sort of one-way valve preventing the loss of boost. This way, as the turbo is spooling, when there is turbo lag, the engine would be using the N/A part of the intake, with the one-way valve as it's source of air, and then when the turbo is spinning fast enough, the valve would prevent boost from escaping. This would basically mean you'd have no turbo lag but still have the power from the turbo when it begins to spool.

[Lith]

I can't speak for everyone here, but my car reaches "0" as soon as I put my foot down even with the bigger GT30R on the car so at least in my case there would be no improvement. Its the spool from 0 to reasonably boost which is what takes the time, unfortunately

[kim0663]

if i understood right,

you're saying that the turbo itself constributes to being a restriction in the intake and therefore introduces 'turbo lag' and therefore removing this 'restrictive' section, get rid of the associated 'lag' ?

Turbo motors being sluggish is more due to the fact of having lower compression than n/a motors, compressor wheel doesn't pose much of a restriction. And ALSO, most, if not all toyota factory bov/bps act as two way valves (similar in function to your idea) to bypass intake air around the turbo straight to the throttle body (or i/c pipe after turbo/s)

Turbo lag is the time it takes for exhaust gasses to speed up enough to maintain/accelerate turbine speed.

This is on the basis for a moderate sized turbo tho... I'm not at all sure if the same applies to huge turbos

What's wrong with turbo lag...? I also thought minor turbo lag would help with preventing detonation in low rpms...

[steve murch]

this is how i see it
the sooner you see it, the sooner it disappears
if you want instant boost use a supercharger
boost thresh hold( not called lag,thats something else) is your friend,only if you want to make power
there is many ways to improve thresh hold without anti lag to which im not a big fan off( anti lag that is )
i have a Honda running one of my systems with two waste gates, one acts as a blow valve back into each exh runner,works pretty dam good and exh heat came down.
again there is other ways,how about injecting fuel into the turbine hsg on back off? boy does that work but you need to replace turbos a little more often,and then there's,well there's many ways.

[Snaps]

Maybe I don't quite have down how a turbo system works, and I guess that's what I'm learning by asking this question. But doesn't turbo lag have the effect of making a engine, when not in boost, weaker than a non-turbo engine? And therefore aything to reduce turbo lag, up to the point where you get positive boost would be good?

you're saying that the turbo itself constributes to being a restriction in the intake and therefore introduces 'turbo lag' and therefore removing this 'restrictive' section, get rid of the associated 'lag' ?

I guess that's what I thought, does it not really work that way?

[fivebob]

One of the more interesting systems I've seen was developed by Cosworth for the WRC cars, and promptly got banned because it was so effective.

Basically it involved large pressure tanks and a couple of bypass valves, when the boost limit was reached the bypass valve opened to fill the tanks. When the manifold pressure was below the boost limit, and the pressure in tanks was higher than in the manifold, the other bypass valve opened and quickly pressurised the manifold.

[frost]

One of the more interesting systems I've seen was developed by Cosworth for the WRC cars, and promptly got banned because it was so effective.

Basically it involved large pressure tanks and a couple of bypass valves, when the boost limit was reached the bypass valve opened to fill the tanks. When the manifold pressure was below the boost limit, and the pressure in tanks was higher than in the manifold, the other bypass valve opened and quickly pressurised the manifold.

i was thinking of this idea a few months ago, didnt know it was already in use/was. sort of like a acu-sump for boost.
only problem was having the room to place said tanks with out it being too far away to be effective.

[kim0663]

I guess that's what I thought, does it not really work that way?

Nope it doesn't work that way. Like i said, compression ratios and alot of other factors i guess

One of the more interesting systems I've seen was developed by Cosworth for the WRC cars, and promptly got banned because it was so effective.

Basically it involved large pressure tanks and a couple of bypass valves, when the boost limit was reached the bypass valve opened to fill the tanks. When the manifold pressure was below the boost limit, and the pressure in tanks was higher than in the manifold, the other bypass valve opened and quickly pressurised the manifold.

So it'd be storing the tanks with ext gas?

[Snaps]

That's pretty smart actually... would make a quick track car if It was implemented into a supra..... (*gets idea for project when I get a TT supra*)

[fivebob]

only problem was having the room to place said tanks with out it being too far away to be effective.

They had big tanks it the boot and some cars were being converted to use the chassis as a tank, before they banned it. Doesn't matter how far away they are because pressure waves travel at the speed of sound, provided there is the flow to back it up you have no lag at all.

So it'd be storing the tanks with ext gas?

No, the filled them with air from the turbo compressor, IIRC they didn't use a wastegate, just run the turbo at max all the time and used a regulator on the outlet from the tanks to keep the boost pressure constant. At the start they filled them with a compressed air so you had boost right from startup.

[RomanV]

Heh that's an awesome idea!

[fivebob]

And a good use for the boot on the SW20

[MAGN1T]

Another trick done years ago was to inject NOS just before the turbine to give quicker spool up. Putting it into the exhaust side got around certain class rules where NOS wasn't allowed. That was in an old book by David Vizard from memory. No doubt there's disadvantages to that too.

Steve

[Lith]

I had pondered hair brained ideas involving using a twin scroll turbo and twin scroll manifold with a bridge area past each tri-y and a kind of gate system which would allow the manifold to force all 6 cylinders to feed a single scroll under manifold pressure (intake or exhaust, depending on what seemed to work better) reached a certain point then split the feeds to individual scrolls once...

[cedwards]

Back to your original idea, pretty much what the GTT caldina does through the BOV, as far as I understand

[RedMist]

Or you could keep the turbo spooled by getting rid of any wank valve you run and recirc blow off it back down the intake throat of the turbo.

[Heylin]

What about some sort of compressed air charge that is stored in a small tank and goes through a secondary turbine on the exhaust side and can act as a pre spooler ?

Secondary turbine as the air going into exhuast side would affect o2 sensor reading.

Not sure how much air and what pressure you would need but it would need to equal or exceed the exhaust flow acheived at maximum boost.

Could be triggered by WOT and mabey have a seperate activator switch.

Off side of that is the charging time required to recompress the air in the tank and the power loss to run compressor while charging.

Could work well for overtaking, drag racing and take offs.

[cogent]

Reading this thread, only one thing comes to mind:

[kim0663]

oh god i lol'd so hard.