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once this is answered by all means please delete, but I have done some research on this forum and need some good advice.

the turbo I am looking at for my 25det is ball bearing

has 0.7 A/R front

0.64 a/r rear.

62mm front wheel trim.

not sure on rear wheel yet.

it is t25 but can get a mate to make me a flange adaptor, also a dump etc.

internally gated, but would look to modify that.

Is new, is cheap for what it is.

Pics:

frontofturbo.jpg

rearofturbo.jpg

Question is that I am after streetable power to 250 or more rwkw. Is this like the GT30/40 where the front is too big for the rear and it wouldn;t be able to spool as quick as a daily driver would like? do I need more info? any help much appreciated.

My mods: Haltech ECU, 600cc injectors, subzero plenum (not a required mod I know) high flow cat and 3" exhaust.

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https://www.sau.com.au/forums/topic/143311-another-25-turbo-sizing-question/
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the problem with choosing ebay turbos and other "from a friend" turbo's is that you have no idea if it will mate up correctly and how it will perform. not to mention the state of tghe bearings and other components. usually they are worse than the stocker unit, plain bearing oil cooled only.

you can take out a lot of guess work by choosing an off the shelf garrett unit. you can look at all the specs and compressor maps and even change the flange options before you order to suit. so theres no lag guess work, no power band guesswork as all the mathematics are there

too often we see peple buy "cheap ebay turbo's" or "get it off a mate cheap" only to find the suck in response and lag and are just generally crappy. sure there are some bargains, but it usually leads to shit to4 style dinosaur combos that suck. much better technology out there

something to think about

I appreciate that, but this turbo is ball bearing and has the 6 blade front wheel, not the dodgy 7 blade one. I have seen these before but am more concerned with the lag. I imagine power will be what I want, but do I need more info for someone to tell me how it should flow on the rb25?

I would stay right away from that thing if I were you , wrong turbine housing for a start (T28 flanged GT28 housing) and the 9 turbine blades usually means a 54mm GT28 turbine . Its hard to tell which compressor it uses but the comp housing looks like TO4S .70AR and too big and bulky .

Too many people buy dog turbos like that and the financial burden of replacing it with a good one is often too much . You are far better off doing some research and spending your money on something more appropriate . If the guys feel this topic is a string of repeats PM me because its only a bit of time on the keyboard , but you'd hate yourself if you went and bought a "Victim Turbo" on mates advise . Plenty of clued up victims try to sell on the sows ear and make the loss someone elses problem .

For your own sake DON'T get sucked in by that thing !

Cheers Adrian .

as i said originally, too many guys buy $900 turbo's and they are poor mans spec with crapstick housings and they just plain suck. then the person has to spend another $1500 to change it and are stuck with a crap turbo. do some research and go for a turbo where you can choose different options and see the compressor maps.

can someone please tell me what the problems would be using this turbo apart from the risk?

it's $3-500 vs $1800.

So if apart from blowing up the worst problem is 500rpm of extra lag because of the exhaust housing being too small??? I am not fussed over a little bit of lag but what could I expect?

I completely agree with you that the prices are awesome, but it's still 3-500 dollars vs 1800 dollars.

My question is will this turbo spool later because the turbine is too small for the front and if so, how bad willit be? At the end of the day for $3-500 the difference in lag is not a problem if it's 500-1000rpm.

indeed it's cheap. Went and saw it in real life last night and it is definitely brand new, no shaft play, bb, the 0.7 a/r front certainly is big. The guy paid 900 for it, it's not genuine garrett obviously.

So yeah, all things being equal I'd get a GT3076 or similar, but they're not equal and I am leaning towards taking the risk on this one.

So does anyone know what it roughly would act like given the details?

probably work Ok, but it'll cost you shit loads of $$$ for the ventolin puffers.......lol It'd be asthmatic.

Let me know when your in the market for some other 'bargains', I reckon I've got a shed full!

:) hahaha,

Ok I get it, the thing will be struggling to push the air out the exhaust.

Point taken.

But as you said, it should work OK (I am not asking it to act like a 35/40 or a 3076 but something the next peg down maybe where I can achieve 250+rwkw at 16psi with a little lag - can't ask for more from a turbo so cheap)

ok, while I appreciate honesty....NO ONE has answered my question.

You all have your opinions which is fine, but I only asked how it would go on the 25 motor, would it have problems with lag or will it run out of puff ot what?

Simple question no one can answer it?

ok, while I appreciate honesty....NO ONE has answered my question.

You all have your opinions which is fine, but I only asked how it would go on the 25 motor, would it have problems with lag or will it run out of puff ot what?

Simple question no one can answer it?

I'd say its going to be laggy, and might make a bit over 250rwkw (MAYBE). It doesn't look like its going to bolt on happily though.

thanks for that, do you know why it'd be laggy?

I know it's not ideal, far from it.....

But I forsee it running out of puff at 6000rpm like my old t3/4 did with a .63 exhaust???

So I would have thought it would come on to boost hard and early but have nothing up top.

Am I wrong?

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