Twin supercharged Exige

[TREY]

ok so forgive me if this is one of those stupid post but has anyone thought about twin supercharging an elise?exige? r is this even possible with the 2zz? i was just thinking about it the other day, and ifg so around how much would this cost?

[lotusforsale]

Originally Posted by TREY

ok so forgive me if this is one of those stupid post but has anyone thought about twin supercharging an elise?exige? r is this even possible with the 2zz? i was just thinking about it the other day, and ifg so around how much would this cost?

There is another recent thread on this somewhere, and I think one or two folks are in the process of trying it.

Cost...well you'd be breaking new ground, so in addition to the $$$ there would not doubt be the emotional cost of trial, error, frustration along the way.

[...m...]

...what do you mean by twin supercharging, exactly?..

...i've heard of twin turbos to alleve spool-up, and twin superchargers feeding each cylinder bank on a v-engine, but i can't picture how twin superchargers might be of use on an in-line engine...

[Thomasio]

On big stationary engines, superchargers have been used in stages... essentially, one supercharger feeds into the next then into the engine.

The 2ZZ-GE is high compression already, there probably isn't any benefit to having more than one supercharger. Not to mention it would be very difficult to fit in the engine bay.

[UmarS2K]

It sounds interesting.

[Amarao]

Originally Posted by Thomasio

The 2ZZ-GE is high compression already, there probably isn't any benefit to having more than one supercharger. Not to mention it would be very difficult to fit in the engine bay.

He would just need to get low compression pistons as with any other high boost build. He'd be in there anyway upgrading the rest of the engine to handle that kind of boost anyway.

[ads_green]

Originally Posted by Thomasio

On big stationary engines, superchargers have been used in stages... essentially, one supercharger feeds into the next then into the engine.

Yep - usually generators.

Interestingly (ok, more "geeky") This is where the term "inter cooler comes from. If you have a charge cooler mounter between two compression stages like two superchargers then it is an intercooler. On cars it's common to call air charge coolers "intercoolers" which is annoying (for me anyway). Both Air and Water based charger coolers in most engines are actually "after coolers" as they happen after all forced compression stages. You can get "before coolers" but these are generally very rare and not too efficient.

As for the toyota... yes you can use dual chargers in theory however modern superchargers are so efficient now that I suspect the engine will reach maximum saturation before the charger reaches it maximum ability to deliver the charge. For example, on the corvette ls7 engine you can supercharge this 7 litre (427ci?) v8 monster with a single supercharger feeding some very big and hungry cylinders. A 1.8 I4 is no where near as difficult to feed so dual superchargers seems less appropriate.

Oh, and the gearbox would explode ;-)

[MpBrady7]

Originally Posted by ads_green

Yep - usually generators.

Interestingly (ok, more "geeky") This is where the term "inter cooler comes from. If you have a charge cooler mounter between two compression stages like two superchargers then it is an intercooler. On cars it's common to call air charge coolers "intercoolers" which is annoying (for me anyway). Both Air and Water based charger coolers in most engines are actually "after coolers" as they happen after all forced compression stages. You can get "before coolers" but these are generally very rare and not too efficient.

Haha, I thought I was the only one who got annoyed with the term "Intercooler". I just conform and use it but anyone who has had any type of thermodynamic education cringes when they hear people refer to an after cooler as an intercooler because chances are they don't have two stage compression.
And yes, technically the only reason to do this would be increased efficiency of the compression stage.

[Bavarian Motorist]

So is an Exige S after cooled or before cooled?

[breinhar]

Originally Posted by Bavarian Motorist

So is an Exige S after cooled or before cooled?

AfterCooler. Air comes through the filter, through the S/C then the Aftercooler/Intercooler then into the Intake Manifold.

[Simba]

You could, in theory, assuming you could work out the packaging (good luck). But it'd have no benefit over simply using a larger displacement single blower.

Some very large (1000+ hp) marine engines in race boats use twin whipples, as a large enough blower for the power requirements and packaging requirements doesn't currently exist, but it's not really feasible or necessary unless you need to move a lot of air.

As with any forced induction system, the method of compression is always going to be based on the power, reliability and packaging requirements. Absolutely no reason to do anything other than a single blower or turbo on a 2ZZ in an Elise/Exige, short of "because I can and want a less efficient, heavier, more complex FI system".

[RENDERMAN]

Originally Posted by ...m...

...what do you mean by twin supercharging, exactly?..

...i've heard of twin turbos to alleve spool-up, and twin superchargers feeding each cylinder bank on a v-engine, but i can't picture how twin superchargers might be of use on an in-line engine...

I had the same question for a little while but then realized the Supra has an inline 6 (I'm I correct on this?) so it is possible a 2+2

[Bavarian Motorist]

So why does a company like Koenigsegg use twin blowers on their CCX?

[Walnuts]

Originally Posted by Bavarian Motorist

So why does a company like Koenigsegg use twin blowers on their CCX?

Its a 4.7L V8 with "twin Rotrex centrifugal superchargers" and, if I do say so myself from seeing it in person, a BIG-A$$ intercooler. Not sure why the did a double, but I would assume it was use smaller units and get more upfront effect without sacrificing top-end performance? Not sure if this applies to rotrex units the same as it would a turbo, but smaller I would think a smaller unit would get into its efficiency range at a lower RPM than a single huge impeller. I don't believe they are in series, rather running parallel. In fact, from the images I found on a quick Google search, they are definitely running in parallel, not series like what I think is being asked about in the original post. That leads me to believe that the issue may have simply been space. They may not have had an adequate footprint of space needed for a single, larger unit so instead they opted for two which had similar/equivalent flow characteristics (combined) and fit into the footprint that was available.