T28 rear housing size & Hi flowed ?

[Kei_ayanami]

T28 rear housing size & Hi flowed ?

Hey guys I'm trying to find out what rear housing size my turbo is but can't seem to find the right info. 

I've got a 200sx - s15 with which I believe still has the factory t28 bush bearing turbo. Does anyone know what the rear housing size is not sure if its the .64 or .86 or I could be wrong all together...... anyways any help  would be appreciated. 

Also Has anyone had any experienced with Hi flowed turbos ?. Correct me if I'm wrong but from what I understand Hi flowing the t28 will mean that it will still spool at the same rpm as it is stock but just makes more boost compared it in stock form at the same rpm for e.g. 

Stock                 Hi flow

 2000rpm          2000rpm
=5psi                 =7psi

and so on wards ?

Does it also mean that the t28 will hold boost right upto redline as well?. 
Are there any downsides or things to worry about when Hi flowing?.


Cheers.

[admS15]

Stock t28 is. 64 housing. Don't bother high-flowing it. Either max out the stocker, around 200rwkw on 98 and 220 on e85 or upgrade altogether to a newer tech modern turbo.

[Murray_Calavera]

Hey mate,

The rear housing size will be stamped on the housing, easiest way to confirm. Our cars don't tend to stay stock for long, I'd just have a look to see if any previous owners have changed things up. 

With regards to the high flowing, you haven't quite got the right idea of how it works. Maybe the easiest way to think about it is, when you high flow you'll have a slightly bigger turbo in the same size package. 

Essentially the way it works, the housing is machined out to allow a bigger CHRA to be fitted. The size of CHRA that can be fitted will be based on how much can be safely machined out of the housing. Other upgrades can be made at the same time, such as ceramic wheels to steel wheels, ball bearing core, etc 

'Holding boost to redline'... it's a bit ambiguous, I'm sure the factory turbo can hold factory boost til redline, if you see what I mean. To try and answer your question though, a falling boost curve can be due to a number of reasons such as the turbo falling out of it's efficiency range. If you do a bit of reading on compressor maps and how to interpret them, this should help you answer your question on if X turbo can hold the boost you want. 

Downsides or things to worry about? Hmm pros: ease of fitment. Cons: you'll probably want a bigger turbo soon lol. 

Hope some of this helps. 

[hypergear]

The stock T28 can be high flowed to make up to 300rwkws on pump fuel. It doesn't get any more responsive how ever. Usually bigger power = more lag.