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How fast does a turbo spin at idle? Roughly?

More than 950rpms? If so, it'd be pointless to have the motor spin it slower?

BAH! ever heard of gear ratios?

have the pulley that spins the freewheel MUCH bigger. hence 1 revolution of the pulley would equal for example 10 - 15 revolutions of the free wheel. :)

too easy!

cheers. james.

How fast does a turbo spin at idle? Roughly?

More than 950rpms? If so, it'd be pointless to have the motor spin it slower?

recalling back to my subaru school training.

on a wrx at idle the turbo spins at between 15000-22000rpm

recalling back to my subaru school training.

on a wrx at idle the turbo spins at between 15000-22000rpm

I wonder if a series of fans in the exhaust system sucking the air out at high speed at low revs.will

give you no lag?These fans could be designed to stop working as soon as boost starts to come on.

Or am i thinking the wrong way.

Do we need to build a pressure loop, at idle it builds and at take off forces the air into the turbos.

This seems an easy concept to dwell on, where is the pressure most needed to spoll these turbo's up quicker?

At pods,turbo's,exhaust manifold or plenum? :)

Lets face it ,if spolling is helped so lessens the lag at low revs.A 1000rpm drop would help almost everyone.

question: i hear that the anti lag systems severely reduce the life of the turbo. although its only hear-say (to my knowledge), it does make sense that it would reduce turbo life.

with the antilag unit i have in the book that it comes with it, it clearly states "that prolong uses on the antilag system will reduce the turbos life"

i have yet to try my system, as when i bought it i was running stock ecu but never install it then i bought an pfc and install it but it fail to work, so it was sent back to GRiD in japan where they are rechipping it to work with the pfc

' date='24 Aug 2006, 11:03 PM' post='2437221']

with the antilag unit i have in the book that it comes with it, it clearly states "that prolong uses on the antilag system will reduce the turbos life"

i have yet to try my system, as when i bought it i was running stock ecu but never install it then i bought an pfc and install it but it fail to work, so it was sent back to GRiD in japan where they are rechipping it to work with the pfc

Garrett are already developing Electric Assist turbos (anti lag), think its mainly for truck turbos atm though

From my understanding it should increase turbo life, not decrease it , as less stop/start which stresses the wheels. The electric motor actually acts like a generator when on full power and recharges itself...

Dont they also have anti lag using an injector (squirts a little bit of fuel and ignites it) which keeps the turbo spooling when coming off throttle?

Edited by Trooper
Garrett are already developing Electric Assist turbos (anti lag), think its mainly for truck turbos atm though

From my understanding it should increase turbo life, not decrease it , as less stop/start which stresses the wheels. The electric motor actually acts like a generator when on full power and recharges itself...

Dont they also have anti lag using an injector which keeps the turbo spooling?

the antilag system i use work using this method:

It will not fire one coil-pack per cyclical, so all the hot air and fuel is dump onto the turbo keeping it spooled up!

' date='24 Aug 2006, 11:17 PM' post='2437268']

the antilag system i use work using this method:

It will not fire one coil-pack per cyclical, so all the hot air and fuel is dump onto the turbo keeping it spooled up!

How effective do you find this? What turbo/s you running?

How effective do you find this? What turbo/s you running?

i have yet to run it as i had to sent it back to japan, to be rechip to work with the apexi powerfc.

im running a hks gt2835 pros and get full boost around 3500rpm, so im hoping the antilag will drop it down abit

Electrically assisting the turbo is probably the best solution. The challenge is feeding the necessary current to drive it which wouldnt really be feasable from the standard 12v car battery. A completely separate system would be needed. Like you said, when turbo is spooled and operated by exhuast turbine, the electric motor acts as a generator. You could assist recharge from standard alternator aswell.

I wouldnt use a belt / pully do drive the turbine shaft from the electric motor as this would be fraught with problems ( some mentioned above ) plus probably wear the bearing from extra tension of the belt pulling down in one direction.

With an electric motor sitting between the compressor and turbine directly driving the shaft you would eliminate any premature bearing wear, etc. The motor would need a special heat shield + cooling system to protect it from high temps.

Definately Possible.

Too complex, too big, too much gearing required to spool the turbo at idle. 1000rpm vs 80,000+ rpm.

They already have a similiar 'concept', its called electrically assisted turbo. Basically a little elec motor spins up the turbo.

140,000rpm you mean :)

And... as for anti-lag.

Not really friendly for a street car by any means as stated, it will kill shit ;)

And... as for anti-lag.

Not really friendly for a street car by any means as stated, it will kill shit

well there goes that idea for my mistress (r32 gts-t in regular terms)

well there goes that idea for my mistress (r32 gts-t in regular terms)

also, ive also read somewhere that the brake system in a street car, uses vaccum or something along those lines from the engine. and when running antilag, the sytem doesnt have any vaccum causing ur braking performace to become very poor

Hey guys engine driven turbo's have been around for ever on big stationary engines.

The 4000hp GM powered locomotives have 2-engine driven turbos.

Start up is different too in that the starter motors are timed to give a small rock, then a bigger one, and then start.

This gets the turbos spinning and prevents the enormous torque from twisting off the turbo drive shafts, which have an over-running clutch for when the exhaust gasses take over.

Not really designed for small engines though.

Edited by grigor

What about surge problems and cam shaft durations. Say the idea did work and you started getting some decent psi very early in the rev range, i doubt the motor would be able or is designed to swallow X amount of air a X amount of revs with cams that are designed to work later in the rev range., unless of course you had some type of way of bleeding of access pressure. Many factors need to be considered when thinking about these things and if one of the jap companys haven't thought of some kind of system now i doubt many other people will... Good effort though! :D

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