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Ive noticed lately that my 1994 r33 gtst doesn't go as hard as when i 1st bought it about a year ago.

i don't know whether its because my stock turbo is on its way out or what but i told my mate about it and he recommended that i get a high flow turbo.

i went to my mechanic and told him and he said why not just get another stock turbo? i asked isn't a high flow better and he said no,there's no power difference and all it does is make the turbo sound likes it winding up more.

is this true?

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probably because you've been driving it a year and you're much accustomed to the power as opposed to when you first got into it... pretty normal

unless you have been to a dyno 12 months ago, and go back here again to see a difference... but i doubt it.

A good check on a dyno, AFR's, fuel pressure and so on is a good thing to do every 12 months either way

Its true what Ash says, its simply just getting used to the power. Had a 250rwkw gts-t back in 2003. Seemed fast when i got it, but them 250rwkw felt slow. If in doubt just chuck it on the dyno... or get someone to take you for a drive whilst you are in the passenger seat. Feels faster there :P

Ive noticed lately that my 1994 r33 gtst doesn't go as hard as when i 1st bought it about a year ago.

i don't know whether its because my stock turbo is on its way out or what but i told my mate about it and he recommended that i get a high flow turbo.

-Your used to the power

-The car is getting older and more worn therefore could be affecting performance

-Something could be wrong, blocked cat, oil build up throughout cooler, plenum, throttle etc

-Needs a service, thick oil, bad plugs etc

Number of things really that could be affect performance, or it's just your imagination

i went to my mechanic and told him and he said why not just get another stock turbo? i asked isn't a high flow better and he said no,there's no power difference and all it does is make the turbo sound likes it winding up more.

is this true?

He's an idiot.

Edited by PM-R33
Its true what Ash says, its simply just getting used to the power. Had a 250rwkw gts-t back in 2003. Seemed fast when i got it, but them 250rwkw felt slow.

I agree, mine standard felt fast when i first got it (i had an nc fairlane before it) now even after a hiflow full exhaust pfc tune and more boost its not fast enough, power is the same as any other drug, will take more and more to get the same thrill, and if you keep chasing that thrill you will end up broke and dead.

or get someone to take you for a drive whilst you are in the passenger seat. Feels faster there :P

I disagree, mine actually feels slower when im in the passenger seat, or maybe i just trust the people who i let thrash my car as i hard as i do, i have a few friends who i would not let drive my car, would feel scary fast if they started going hard in it.

i would strat looking for a new mechanic, mate. though with a high flowed turbo if you run standard boost you will make standard power with some more lag.

sorry but wrong.

first dyno is a standard on 12 psi and second is a highflow on 8 to 11 psi

post-24566-1239536796_thumb.jpg

post-24566-1239536810_thumb.jpg

what happens when you hiflow the turbo?

you replace the compressor wheel, bearing pack, exhaust wheel, bore out the exhaust snout and realign and balance all the components. the result is a brand new turbocharger in a an old 2nd hand housing / cover

the standard GTST turbocharger is a ball bearing, oil cooled, water cooled unit which is fantastic off the bat

the typical hiflow that costs 2k upgrades all of these components to higher flowing spec items (compressor and exhaust wheels) and basically services the turbocharger to a brand new unit, youll also get a steel exhaust wheel (vs ceramic).

the end result is the new compressor wheel is larger and can flow more air at the same pressure

the exhaust snouth is enlarged to fit a lager exhaust wheel, which in turn can drive a larger compressor wheel

the end result as a final package is more average power for the same level of response (as you keep the same std housing size) for very little loss of power/response and to top it all off any spastic can refit the highflowed unit as its the same as the std unit. bolt off, hiflow, bolt on, refit and away you go, everything mates up first shot and it looks factory.

the main cost component of a ball bearing hiflow is the 2k, which comes down to the ball bearing CHRA and rebalancing. you can get pesant spec hiflows ie plain bearing, thrust, journal etc for cheaper, but they obviously have draw backs.

the std unit is ball bearing so keep it that way to maintain linear response and reliability

the main issue is you cant buy a "stock" turbocharger brand new

youll have to rely on a garrett / hitachi equivalent etc so it wont be a prefect match

and its likely it wont mate up correctly, ie dump might be different etc.

when you highflow your existing unit, its the same as a new turbocharger

as all the bits that wear out, are replaced and rebalanced (this is where the cost comes from)

the only tthing retained is the housing and covers, and they dont wear out

I was about to ask why bother reusing the old housing, but you answered that in your second post.

I heard some rumors about garret coming out with a direct bolt on turbo soon, this true?

I was about to ask why bother reusing the old housing, but you answered that in your second post.

I heard some rumors about garret coming out with a direct bolt on turbo soon, this true?

Already have, been out for a while, cant remember what model it is though.

I am also pretty sure that it is not a 100% bolt on, its mainly the exhaust housing, still need to redo the oil and water lines and new piping for inlet and outlet of the comp cover.

2 things pop into my mind..

1) Why do you think your turbo's on its way out?

2) If you mechanic says the hiflo is no good, he is right and wrong - right because of your stock ecu parameters - and it WILL be a lil bit laggy. Wrong because well.. i could go on n on.

2 things pop into my mind..

1) Why do you think your turbo's on its way out?

2) If you mechanic says the hiflo is no good, he is right and wrong - right because of your stock ecu parameters - and it WILL be a lil bit laggy. Wrong because well.. i could go on n on.

i have noticed lately that the car just doesn't go as good as it use too and it seems to take longer for boost to kick in and when it does it aint offering much.

i know some guys are saying its me getting use to the power but before i owned the skyline i use to own a VN commodore-turbo.

i got it turbo charged and that thing goes harder than my skyline.

so its not like Ive gone from a ford laser to a skyline with a massive power difference and im now used to the power.

its the town im in,all the mechs think they know all about turbo's but when you try to explain something to them they have no idea what im on about.

im running a hypergear highflow and its absolouty madd!!! it costed it costed me 800 or 850 i cant remember, it handles madd boost and its not laggy either! if you want to save money get a highflow man.. :P

i have noticed lately that the car just doesn't go as good as it use too and it seems to take longer for boost to kick in and when it does it aint offering much.

i know some guys are saying its me getting use to the power but before i owned the skyline i use to own a VN commodore-turbo.

i got it turbo charged and that thing goes harder than my skyline.

so its not like Ive gone from a ford laser to a skyline with a massive power difference and im now used to the power.

its the town im in,all the mechs think they know all about turbo's but when you try to explain something to them they have no idea what im on about.

Taking longer to boost - How much are you actually boosting? Just because its taking longer to boost doesnt mean its a stuffed turbo. It could fowled plugs/misfire etc.

You do have an aftermarket boost gauge, right?

It could be something as simple as retarded timing causing your issues.

When did it last get a good service?(oil change/plugs/filters).

Start from the basics first.

Taking longer to boost - How much are you actually boosting? Just because its taking longer to boost doesnt mean its a stuffed turbo. It could fowled plugs/misfire etc.

You do have an aftermarket boost gauge, right?

It could be something as simple as retarded timing causing your issues.

When did it last get a good service?(oil change/plugs/filters).

Start from the basics first.

its running stock boost as far as i know,i do have an aftermarket boost gauge but haven't got it installed because of the cops in my town they absolutely hate anyone with a turbo charged car p-platers and full licensed included,as soon as they see a boost gauge or a FMIC or anything that don't look stock they defect you on the spot.

i had a service about 2 months ago,new spark plugs,new filter,new oil: motul turbo light 4100,new water pump and a brand new timing belt.

my car is stock except the exhaust system.

my mate not too long ago took of my rocker covers and painted them and noticed the throttle housing was putrid so he cleaned it all and took off the plenum also cause it was dirty and he put it back together and the difference was the car was revving at 1200rpm instead of 850rpm where it normally was.

could that have anything to do with it?

Edited by blitz r33

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