Has anyone fitted a gt3071r turbo with 3" inlet?

Hi guys,

My turbo is in for a rebuild and the guys at Owen Developments recommend changing the compressor to a 0.60A/R with a 3” inlet, from my 2.75" that I have at the moment.

Has anyone fitted one with a 3" inlet before and know if it will bolt straight on? or if the standard manifold will need spacing out so that it doesn't foul the engine/gearbox?

When I originally bought my turbo I had the choice of a 4" inlet which needed the manifold spacing out, or the 2.75" which bolted straight up snugly.

Thanks for your help,

Ben.
 
P

pulsarboby

Guest
yep it will fit with little modification ben

you need to fit 2 x mls ex manifold gaskets (will take it away from g,box housing) you may find youll need to shave a bit off the g,box housing where bolt goes through but thats easy enough to do, if you dont it will be very tight getting a silicone coupler on the tubby intake.
im assuming you have an uprated wastegate actuator (smaller type) as the bigger type wont fit on there without modifying a special bracket for it
 

jamesgtir

Member
not sure on the 3071 jay but my 2871 had to be spaced using two metal manifold gaskets & i also had to grind abit of the block & gearbox. i can find pics if needed.
 
Cheers Bob and James.

Bob, what are "mls exhaust manifold gaskets"? At the moment I have a multi-layered metal gasket, from an s14 I believe?

With 2 gaskets will the exhaust still fit ok?

And yeah got a smaller uprated actuator when I first bought the turbo. Snug but all fits nicely.

James if you've got any pics that would be handy, although I'd imagine it'll be pretty obvious once I get the turbo back and dummy mount it.

Thanks a lot guys.
 

red reading

Active Member
Mls= multi layer steel s14 gasket, as others have said just grind the gearbox and engine castings where the turbo will foul and it will fit.
 
Cheers Dan. Will give them the go ahead with the 3" inlet and get the uprated heat shield and bearing cages done at the same time.
 

red reading

Active Member
Get yourself a oil filter to go in the oil feed to the turbo too, after having a turbo expire from a bit of sump pan paint block the oil restrictors in the turbo I always fit one now, if you are wondering how that happens it is because the oil filter gets by passed when the oil is cold when you first start the car to stop the filter from being over pressure'd and it is there for un filtered oil going thru your engine,
 

gtirx2

Member
Although i have still not brought one yet as i am still yet to put my shitter back together lol i did abit of looking into oil feed filters a while back and there are alot of shonky looking designs out there.

I came to the conclution that the only one i would fit is the peterson -4an 60micron 700 series one.expensive but when you compare it to other designs out there it dont seem a bad idea to me.

http://www.petersonfluidsys.com/filter_700.html
http://www.maperformance.com/products/map_EVOX-OFL-filter.jpg
 
Here's what they said after inspecting my turbo -

"Although there is a little wear to the ring seals , it is not enough to result in the scale of the oil leaking. There is oil leaking from both the turbine and the compressor end, this would indicate there is either excessive oil pressure or insufficient oil drainage. The exhaust housing is severely distorted and buckled, the waste gate no longer seals and the scroll has buckled to the point it has rubbed the turbine wheel. We also found damage to the turbine drive blades caused by impact from debris.

For 400BHP plus running a 0.86A/R turbine housing is a must. To achieve your goals of 450BHP we would also recommend changing the compressor to a 0.60A/R with a 3” inlet. Also if replacing the exhaust housing, a slightly larger turbine wheel can be used for a bit more power."

And then I asked if it was really necessary as thought it would be a lot of work to change and they replied -

"We will try and persuade you to fit a 3” 0.60A/R cover and I’m sure we have had people fit this cover before with not too much trouble? The 2.75” cover is rate to 400bhp you will be lucky to get more not to mention the wheel is designed to run with this cover."

I'm concerned with why the exhaust housing buckled as obviously don't want it to happen again. It may be due a build in exhaust gas due to the standard exhaust elbow or perhaps where I used a very restrictive db killer on a track day last year.

Thanks for the info regarding the oil line filter. I'll organise one and get it fitted when I re-fit the turbo. Do they just screw into the turbo and then am I able to fit my existing oil feed line onto it?
 

ashills

Active Member
I have done 460 on the 2.75 cover so you should have no issues on the 3" with the good bearing cage should be a strong turbo.
 
"We will try and persuade you to fit a 3” 0.60A/R cover and I’m sure we have had people fit this cover before with not too much trouble? The 2.75” cover is rate to 400bhp you will be lucky to get more not to mention the wheel is designed to run with this cover."
Sorry but that is absolute shite, tell them to piss off as this is a blatant attempt to sell you something you do not need.

Compressor cover A/R has very little effect on performance but generally shifts the peak efficiency up and down the compressor map, which maybe of some extremely slight benefit to you depending on how much boost you are running. Is it worth replacing a perfectly good cover for though - in a word no.

as for the inlet, the amount of flow is dictated by the impeller inducer diameter not the the cover inlet. A larger inlet will help with surge margin but unless you are running into very hard surge under acceleration (which you won't be with a gt3071 on an sr20det) then its a waste of time. This is the sort of bullshit I would expect from turbo dynamics etc., thought Owen's were better than this sort of thing.
 

MarkTurbo

Well-Known Member
I was going to say pm Allen as he made 460 on his 3071 but I wasn't sure which housing it was but no need now :lol:

I had the 2.75 inlet on mine too and it had a lot more than 400 ;-)
 

PobodY

Moderators
Staff member
I don't know... do I believe Dr Ed or some guy in sales? Sure Ed has the knowledge and science to back-up what he says, but they guy trying to sell you stuff has probably done this to hundreds of other people (so he must know what he's talking about).
 
I don't know... do I believe Dr Ed or some guy in sales? Sure Ed has the knowledge and science to back-up what he says, but they guy trying to sell you stuff has probably done this to hundreds of other people (so he must know what he's talking about).
Sales man every time :lol:
 
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