nowtype

You already have the downpipe? Isn't that putting the horse before the cart? If you don't have a downpipe yet, just buy a turbo and let your welder figure out the rest.

www.atpturbo.com has anything you could want. Their pricing is a bit steep typically, so find a turbo you want and contact a vendor on here to get the best pricing possible. I don't know your options as far as UK vendors, but I'm sure there is someone over there.

EDIT: I just read the whole thread.

Turbo oulets rarely are the same as the exhaust size. Don't worry about it. It doesn't matter. Finding a 4 bolt housing is not hard. They are common. Just order the turbo you want. Measure the flange on your downpipe and confirm it will fit the turbo you order. It is very simple. I should also mention you are doing everything *** backwards. A lot of these parts are not really interchangeable and if you just start swapping parts back and forth, you will run into a lot of fitment issues. I hope you have a friend with a welder and some skills so you can cut and fit the parts.

xchipx

The problem is i already bought the turbo kit from someone.
The downpipe is a 3" 4 bolt connecter.

Welding is no problem.

However it would be a little pointless putting a 2.5" outlet turbo onto a 3" downpipe/exhaust ?

Also, my inlet tubing is 2.5" so ideally the turbo outlet needs to be 2.5", but then again thats not too important as far as i know.

nowtype

It doesn't matter if the exhaust outlet is 2.5" and you are putting a 3" exhaust. It doesn't make a lick of difference in the practical world. It only matters to the overly anally retentive.

Same goes for the cold side, but I prefer to match cold side sizing up because silicone reducers are a lot more expensive than straight pieces and 2.5" piping is as common as can be.

xchipx

Yeah but it makes a difference that the turbo 2.5" 4bolt pattern is 3.5" bolt spacing ( across ) and that the 3" downpipe 4bolt is 3" and 7/8th's

So at the end of the day it would probably be easier and cheaper to just get a 2.5" downpipe , but it worries me that will restrict over 300whp.

nowtype

Buy this: http://weirtech.ca/catalog/product_i...55f3fee387381c

Take your current DP. Cut off the flange. Weld on new flange.

Don't make things complicated. A $8 flange should not keep you from doing anything. Cut it off and weld something else on.

12sec14

If you really want to chase the 300WHP (good luck) then sell the cheap turbo and downpipe!

Get a GT28R and get a custom downpipe.... 16 psi and hardly any lag.

If you want more later on then sell the turbo and go for a bigger one.


1 question. Why settle for loads of lag when you don't have to? My old white VTT that Dean got off me had max boost by 4.5k. Even that was too much...


Don't go for cheap Ebay ss auto crap turbos. They could cost you an engine.... Low blow they might just do but once you wind the boost up it will eat its self and spit the turbine blades into your engine!

TheShodan

iTrader: (14)

Umm. No. many of the turbo kit manufacturers use a 2.5" outlet to have 3" downpipe welded to it. Its not at all pointless. They either go to the edges of the weld flange themselves to start opening, or they use a conical to turn it into a 3". MANY of the T31 4 bolt housings are 2.5". There's nothing wrong with that. You're fine. Don't over think this

jDMJeRk

Some of you guys just dont understand that when your picking out a turbocharger you have to set aside the idea of "upgrading down the road" or "I might to this/that". You spec a turbocharger given off of what your CURRENT engine setup is for optimal results.

Worry about outgrowing the "smaller" turbocharger before you set your eyes on something bigger thats useless to your setup currently.

its always about peak HP numbers.. well unless your a dyno queen

Good luck