Turbo Lag Solution

[350HP930]

Check out this interesting pic of a turbo and supercharged nissan skyline motor.

As most of you may already know one of the downsides of using a turbo on a motor that is large enough for high RPMs is that there will be no boost at the low end and lots of lag.

Well, it appears that someone decided to try the mad-max idea of adding a supercharger with an a/c clutch to make boost down low and then disengage when the turbos kick in.

Hmm, how long will it be before some some wiley porsche owner decides to do the same thing?

[Type961]

Well, japanese engine tuners often use compressors to advoid lag on large turbo engines. since in europa we often tune engine for race only (since laws don't alloy any modification on road) and prefere to develop turbo or NA engines.

This one is particulary pretty isn't it

[ChrisBennet]

The Lancia Delta S4 rally car (1984 ) had a turbo and a super charger.
-Chris

[cowtown]

That's an awful lot of plumbing. If you're going to drive a supercharger so you can eliminate lag, why not use just the supercharger? Are they that much less efficient than turbos in the high-rpm range? I guess the belt-driven aspect robs horsepower, but I'd think you would take a similar hit in a lightweight car by strapping on two 10-pound turbos.

[tobluforu]

That's one hell of an engine, but will it fit back in the car?

[emcon5]

Originally posted by cowtown
That's an awful lot of plumbing. If you're going to drive a supercharger so you can eliminate lag, why not use just the supercharger?

Because it doesn't have the bling-bling factor that so efficently separates nitwits from their money.

Tom

[911pcars]

I think it's basically called .... packaging.

Imagine twin turbos w/wastegates, a supercharger, an intercooler and associated exhaust tubing and plumbing under the hood or thereabouts.

Good idea though.

Sherwood Lee
http://members.rennlist.org/911pcars

[Pete Pranger]

It doesn't look like it's plumbed according to the flow diagrams on the wall. The way it's done here it looks like they would get a good deal of reversion. I wonder if they have a clutch (similar to an A/C compressor) on the supercharger to disengage it at higher RPMs. I think the better way would be with sequential turbos. Since you are already plumbing in 2 turbos, run a larger one(high speed) and a smaller one(low speed).

Pete

[350HP930]

If you look at the picture you can see there is an electric clutch on the supercharger.

When looking at the pic I too wondered what they did to keep the boost from blowing back through the turbos before they could spool up so I am assuming that they have some type of valving in the plumbing to prevent that from happening.

[thabaer]

The pairing has been around for decades on commercial diesels, don't know any details on the pros/cons.

Never mind, didn't look at the plumbing at first and noticed this one is not a sequential setup.

[TurboRuf]

The old supercharger + twin turbo's trick...

Meet Mr. Willy König's creation...

[Wayne 962]

This was an idea that I had been kicking around for a while. It would indeed be tough to implement...

-Wayne

[thabaer]

OHMYGAWD!!!

Waitaminute: where's da belt-driven supercharger ? The red block on top or is that a centrifugal for the first stage... or is that a smile on your face

[island911]

A much more elegant solution to this is a turbo derivative called a hyperbar.
It was thought up, a while back, to have a turbo'd motor that can achieve boost at even zero engine rpm.

It essentially consists of integrating a compressor side bypass, plumbed to the turbine side. (inserted pause for WTF? )

. . .the trick is, a gas fed flame tube in between. (your turbo is now essentially a simple turbine engine)

This, in effect, decouples the boost as a function of piston speed, and produces boost where (when)ever you like.

Of course, it's not very fuel efficient . . .but it doesn't steal crank power either.

[Tyson Schmidt]

Do they have twin calipers at each corner? Street pads in one for cold braking, and race pads in the other for hot?



Seems to me they could've bought a Viper GTS for the money they have into that engine. No lag there!

I don't see the point. When it's all said and done, there will always be someone with a faster car. But then, I just don't get Drag Racing. Well, not since I've grown up anyway.

[1fastredsc]

A much simpler solution (although most look at it as the nectur of satan) is to setup an off boost NOS system. Essentially it's a system that'll shoot NOS into the motor until boost of any kind is detected and then shut off. Small shot usually, but just enough to provide more heat to the exhaust and spool up the turbine quicker. I kind of like the late hitting lag, but this is a inexpensive solution.

[dean]

[i] Well, not since I've grown up anyway. [/B]

How did you do that?

[tsuter]

If I were to do it again I think I'd do a twin turbo setup with GT20s or 22s. Those little babies come on FAST!