Open-ended budget 4AGE build - with some restrictions

**oldcorollas** · 05-03-2010, 12:16 PM

ahh rotrex... lag of a turbo with mechanical loss of an SC... best of both worlds...

i suppose the linearly increasing boost makes it easier to drive

or good for dyno queen?

**mattysshop** · 05-03-2010, 02:12 PM

well if that is the blue S2000 he was talking about... it may make 350hp on the dyno... but it's not that impressive on the highway

not against other cars with less or the same power.. still quick though..

**the_random_hero** · 05-03-2010, 05:26 PM

Originally Posted by mattysshop

is your mate with the honda brad? VTEC plates on a blue S2000?

i thought you might know craig, i think i've dropped into your work with him a few times when i've been helping him out..

Yes to both accounts.

Originally Posted by oldcorollas

ahh rotrex... lag of a turbo with mechanical loss of an SC... best of both worlds...

i suppose the linearly increasing boost makes it easier to drive

or good for dyno queen?

Power response is very linear, he's currently in the middle of getting a larger blower, stronger diff and then upping the boost somewhat.

Fresh from customs today

Originally Posted by mattysshop

well if that is the blue S2000 he was talking about... it may make 350hp on the dyno... but it's not that impressive on the highway

not against other cars with less or the same power.. still quick though..

He is yet to give it a real stab on the roads or on the strip, he's too much of a bitch worrying about his diff (apparently they are incredibly weak when you throw boost into the mix).

**oldcorollas** · 05-03-2010, 05:33 PM

it's linear in that the boost is linear with rpm..
ie low at low rpm, then high at high rpm

so you get a steeper linear power curve than if properly SC'd, but missing all the midrange

good for dyno queens or drag cars that only need a small high rpm range..

ie,
top two (flat) curves are SC's (eaton starts ok and goes down at higher rpm, KB starts lower and picks up with rpm), the middle one is typical turbo..
the lower curve... is centrifugal charger... looks pretty shit really....

**Duk** · 05-03-2010, 05:55 PM

1 thing to note about that test is the displacement of the Eaton versus the Twin Screw SC.
An M112 displaces 1.836 litres/rev. The Twin screw is a 2.2litre/rev.
The Eaton was turning at over 19000rpm.

**oldeskewltoy** · 06-03-2010, 03:48 AM

The Rotrex has what they call traction drive technology -more advanced, but similar to a plantery gear drive system... so it a fair amount of boost earlier and holds it better then a conventional centrifugal S/C

http://www.rotrex.com/Home/Technolog...t_Concept.aspx

**allencr** · 06-03-2010, 03:58 AM

Originally Posted by TERRA Operative

Also, for longevity, get two sets of main and rod bearings. Match up the bearing halves with the groove in them so the oil can circulate all the way around the bearings.

I would not do this and I don't think that you'll find any valid reference except for going to 200 or 240 degrees, not 360. While it lets the mains do more rod oiling, their reduced load capacity doesn't help. Also, grooved rods are are going to be very difficult to find!

**mattysshop** · 08-03-2010, 09:02 AM

Originally Posted by oldeskewltoy

The Rotrex has what they call traction drive technology -more advanced, but similar to a plantery gear drive system... so it a fair amount of boost earlier and holds it better then a conventional centrifugal S/C

http://www.rotrex.com/Home/Technolog...t_Concept.aspx

how hard are they to spin vs eachother?? do they measure a coefficient??