HKS GT Supercharger (Rotrex) in development!

[mines13]

Originally Posted by madfast

http://ameblo.jp/nob-taniguchi/

its says:

この仕様で250馬力です。

エンジンがまるっきりのノーマルの為、ブーストも抑えめの0.6

これ以上ブーストをかけるには、
ピストンとコンロッドを交換しないと、壊れちゃう…かも。

which google translates to:

250 hp in this specification. Normal for Marukkiri, 0.6 second boost engine is also reduced to make a boost more than this, and do not replace the piston and connecting rod, will break ... Perhaps.

Maybe they intended (.6 bar which is roughly 10psi) and any more then this you need to upgrade the stock internals. Which means I wouldn't want to run more then 8psi. But this is just speculation on my part.

[serialk11r]

Hmmm that's a pretty small compressor for a supercharger setup if I'm not mistaken, usually they go with pretty large compressors (presumably so they don't need to gear it like 15:1). 78hp increase measured on the dyno is about 90hp at the crank. I don't know what superchargers usually give but that sounds like about 0.7-0.8 bar boost, just going off air mass + efficiency losses.

[madfast]

list of HKS/Rotrex GT Superchargers found here:

http://www.hks-power.co.jp/en/produc...ger/specs.html

[uspspro]

Originally Posted by serialk11r

Hmmm that's a pretty small compressor for a supercharger setup if I'm not mistaken, usually they go with pretty large compressors (presumably so they don't need to gear it like 15:1). 78hp increase measured on the dyno is about 90hp at the crank. I don't know what superchargers usually give but that sounds like about 0.7-0.8 bar boost, just going off air mass + efficiency losses.

It looks like a modified C30-94 (modified the inlet for a bolt on piece)

That is the unit that made 292 rwhp on my 1zzfe, and is very compact.

The HKS GTS7040 looks like it's built based on the Rotrex C30-94

[Cessblood]

I wonder if it's 250 with a full exhaust system or without.

[86design]

okay I am now saving my shinny pennys for this supercharger!!! its a for sure thing now!! lol

[toxicdrift]

Originally Posted by Cessblood

I wonder if it's 250 with a full exhaust system or without.

they definately had a exhaust system on it. its seen in almost all the hks videos.. i think if priced right this kit will definately be a must have mod, as most are lookin to mod their cars upto 250 and under 300.

[WingsofWar]

In testing stages..hurrah..bumping the picture!

[uspspro]

The Rotrex has so many good points. Sure it won't make the mid-range punch of a properly sized turbo, or the off-idle torque of a roots/twin screw, but it has several things going for it. I had one on my MR2 Spyder for a good while, before I went with the 3.5L V6 swap.

1) It's quiet. They use planetry rollers with traction oil, instead of gears. So there is no gear whine like other superchargers. I view this as a plus, I like the sound of the engine not to be drowned out by the SC. It will make the engine quite a bit louder and more "serious", lots more induction sucking sound and louder exhaust. The sound is awesome, and this is a huge plus IMHO.

2) It is reliable. Self contained oiling system with oil cooler, reservoir and filter. Alll of the components are compact, and can be installed easily. Rotrex is also the OEM supercharger for the Koenigsegg ccx (although they use two of them)

3) The boost ramp is much better than typical centrifugal blowers. The planetary rollers, high gear ratio, and well designed compressor housings allow the boost to ramp up quickly.

4) The use of restrictors. You can place a restrictor on the compressor inlet, which allows a maximum air flow, thus limiting the maximum boost. This allows you to use smaller SC pulleys to spin the SC up to higher boost numbers at lower RPM, but not have some stratospheric max boost. For my build, I used forged 9.0:1 pistons, so I did not use a restrictor and boosted up to 17psi. However for a stock bottom end with high compression, the restrictor makes perfect sense. Imagine a pulley capable of delivering 15 psi at redline, but with a restrictor keeping it at 8psi instead. You will probably see that 8 psi pretty early in the mid-RPM range and then it will hold that boost level. HKS has information about restrictors.

5) Packaging and heat. The compact packaging allows for good placement in the engine bay, and makes it easy to install an intercooler. Also, the SC produces MUCH less heat than a turbocharger. This leads to a more reliable setup: Easier to keep temps in check, less "baking" of engine bay components, better intake air temperatures.

I think a 250 rwhp Rotrex kit would be perfect for this car, IMHO... And, if they so chose, power-mongers can change out the restrictor and pulley along with a built bottom end and go for 350+

[Turbowned]

Originally Posted by WingsofWar

In testing stages..hurrah..bumping the picture!

YESSSSS! EPIC. Cue the Fry "shut up and take my money" meme!

Not thrilled that it sits right at the front of the engine bay, but I suppose there's no other place to put it with the engine being so far back and between the strut towers. Couldn't they have put it to the right of the alternator?


Now to begin explaining to the flocks of n00bs "no, it's not turbo, for the hundredth time!!!"

[SkullWorks]

no unfortunately it is not, it just wishes it could be....

[chate]

Awesome! I can't wait to see what comes of this...and if it passes CA smog :/ :praying:

[uspspro]

Originally Posted by SkullWorks

no unfortunately it is not, it just wishes it could be....

Trust me... it's better.

Despite what the numbers and bench racers say.

[madfast]

Originally Posted by uspspro

4) The use of restrictors. You can place a restrictor on the compressor inlet, which allows a maximum air flow, thus limiting the maximum boost. This allows you to use smaller SC pulleys to spin the SC up to higher boost numbers at lower RPM, but not have some stratospheric max boost. For my build, I used forged 9.0:1 pistons, so I did not use a restrictor and boosted up to 17psi. However for a stock bottom end with high compression, the restrictor makes perfect sense. Imagine a pulley capable of delivering 15 psi at redline, but with a restrictor keeping it at 8psi instead. You will probably see that 8 psi pretty early in the mid-RPM range and then it will hold that boost level. HKS has information about restrictors.

what was the redline of your build? do you know what the max impeller speed was on your set up? here's what im thinking. stock 7400 rpm is kinda low. so if you build the engine to handle 8500 rpm, you would have to size the pulley to keep it under max impeller speed right? and how much of an impact would that have at lower rpm?

i believe you posted a dyno before, but do you have a boost graph of that run? what rpm was peak boost?