$350 Turbo made 253rwkw @ .9bar

[BOOSTD]

The turbo has been re-installed with the groove in the inlet snout. Surge is absolutely non existant in any gear at any boost. The groove was copied from the standard R33 turbo. 3mm deep, 3mm past the compressor blade and 1cm wide.

[Steve]

Dyno????

Huge potential for your own little cottage industry here:)

[B-Man]

Boostd - I don't understand the groove inlet on the snout thingy... (my small brain). I can't tell from the pic either sorry... I think I need to see in real life or explained with one in fromt of me , for me to understand.

BTW - I had a good look at my Exhaust housing yesterday at UAS as they had another one there. The exhaust wheel port had been fully bored out to max, and exhaust wheel fits nicely - no gap at all. The core is 550-600HP garett (same as 3040)..... I think. My compressor housing is T04e (bigger than T04b, I am told) which clears manifold as mine is tubular. All wheels are steel. Compared it to another Garett housing there (dunno which one), and mine is much bigger by the look of it.

As side note - I don't think my boost problem isn't surge as the boost doesn't fluctuate - it's more likely a restriction somewhere as boost drops off suddenly at high RPM and high boost. We have and idea it's the cat - but this is not proven yet (Tuesday will tell) and if it is so, you will not beleive the story/theory to this.

After boost problem is fixed, I'll let you know the dyno numbers.

/edit - changed is surge to isn't surge - DER !

[BOOSTD]

Just have a look at a stock R33 turbo, the groove is exactly the same. Maybe your boost drop is from your waste gate actuator. Mine also did that before I installed a HKS actuator.

[B-Man]

Std Turbo - Yeah - I'll have a look !

Wastgate actuator - nah, that was the first thing they changed....

We are pretty sure the cat is melted, there is a reason for that too, and another reason why the reason for the melted cat is the way it is. It all makes sense when you add it up....

But it was too late to pull the cat off and look at it - Will be done Tuesday.

Cheers,

[BOOSTD]

sounds complicated :confused:

[Jay95R33]

B-Man - when it running up on the dyno, make sure the pipe from the AFM to the turbo isn't sucking closed. It could be causing it too.

J

[BOOSTD]

Very good point, something I also need to look at. Greenline do a intake kit from Apexi which looks awesome, but, includes the filter and cost around $500

[B-Man]

Jay - yep checked that pipe - it was the second thing we looked at after the wastegate actuator.

Its a long story, which I will post a new thread about it later, after we have proven the theory. Suffice to say that I had a week of troubleshooting (before this) where the car was running rich as buggery. Eventually tracked this down to the setting for my AFM (Q45) being changed after I changed the battery in my car, because it died, because it had been sitting around doing nothing for so long while waiting for the engine re-build.

Running rich during all the troubleshooting must have melted the cat. causing the restriction at high boost & high revs. Added to this, pieces of crap coming out the exhaust while on the dyno, it will prolly blow the whole exhaust clean off soon ha ha ha -

Anyway, we found all this out at like 5:00pm Saturday and everyone was keen to pack up - so it awaits the hoist and removal of the cat for inspection tomorrow.

Fingers crossed it is only the cat.

And yes, I know a PFC shoudn't loose the settings for AFM when the car battery has been replaced - This bit doesn't make sense - But this was the sequence of events ... I'll be testing this out too - Maybe there is a little bug - or maybe someone changed the setting inadvertantly.

Oh, well that's the whole story now....appologies Boostd for thread hi-jack.

[B-Man]

Confirmed - Blocked / Melted cat - yay ! Should be fixed today ! I'm happy !

[Jay95R33]

Confirmed - Blocked / Melted cat - yay ! Should be fixed today ! I'm happy !

Good stuff, easy fix.

J

[EnricoPalazzo]

Crazy theory. Well done. Hope everythin works out from now.

[BOOSTD]

No probs at all b-man. sounds like every day will be a wet day for you to soon =)

[BOOSTD]

Hey Steve, sorry no dyno as yet. Soon I promise.

[BOOSTD]

Made 245rwkw on 10psi

more boost soon.

Doesn't make 15psi till 4600rpm due to reduced gas velocity with my ported head.I Will have to customise to suit. I am looking at reduceing the turbine snout quite abit and using a external gate and internal to enable higher turbine speeds and still flow well with the smaller outlet...call me crazy but it keeps me busy.

Rb20 works well with this setup using .6 A/R exhaust housing and 52mm snout.

[whatsisname]

Get the tuning completed and hit WSID. I wanna' see those numbers tumble Matt!

[BOOSTD]

You and me both matty.

No go having good power without good average power tho.

When does ur turd make 1 bar ?

[rbs13]

boostd. just saw you posted 245rwkw on 10psi.. what turbo is this related to may i ask.. im a bit lost with all the talk from the melted cat etc haha. what are the specs of this turbo? thanks mate. and when you say its alright witha .6 exhaust housing on a rb20.. do you have any power figures and spool revs etc? cheers.

[BOOSTD]

Made 240rwkw @ 17psi with 1bar @ 4100rpm on a rB25 internally stock.

[sprint32]

Hey guys, what about boreing out the internal wastegate and fitting a larger wastegate 'flap'? Could this reduce enough backpressure to warrent not machining out the turbine housing as much? Thereby making it more viable to fit on an rb20? what about other smaller compressor wheels, would that be smoother and prevent surge problems?