As the title indicates, im interested in upgrading turbos. The 15g is getting boring and im tired of the initial boost spike and drop I get. I know the gt28rs would be a great update, but for my power goals it would be overkill. would the gt28r suit me well as an upgrade and put me at around 225whp on anywhere from 8-10 psi? TIA

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by PA MATT &raquo;</TD></TR><TR><TD CLASS="quote">As the title indicates, im interested in upgrading turbos. The 15g is getting boring and im tired of the initial boost spike and drop I get. I know the gt28rs would be a great update, but for my power goals it would be overkill. would the gt28r suit me well as an upgrade and put me at around 225whp on anywhere from 8-10 psi? TIA</TD></TR></TABLE>

I want to know this too.

I also want to know if you can retain A/C with the GT28R and a 2.5" - 3" downpipe

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by boostincoupe &raquo;</TD></TR><TR><TD CLASS="quote">

I want to know this too.

I also want to know if you can retain A/C with the GT28R and a 2.5" - 3" downpipe </TD></TR></TABLE>

I was told it is nearly impossible to retain A/C with a GT28R because of the way it has to be mounted. You would need to use to a Greedy elbow that comes with their kit which is hard to find separately and very restrictive.

 

yeh, keeping a/c would be nice even though i dont use it all that much. It's nice to have on rainy, humid days. So would this be a worthwhile upgrade for my power goals?

 

IIRC the GT28RS makes 300 as a near-limit at 15psi or so, and the GT28RS is below that. Basicly whatever's good for an LS, the next step down is perfect for a D, which would be the GT28R. It was something like ~24lbs/min at 7500rpm for 10psi, which should be good for 230-250 whp on a honda.

 

youll be better of with a 16g, if 225hp isyour goal, Im not sure if youd make that much at 10psi on a d series though. Maybe someone else with a 16g'd d-series can chime in .

 

I know 93turbo16 is running a hybrid 16g and is putting down around 230whp on about 15 psi.
Also, the compressor flow is 31lb/min on the gt28r

 

the t28/t25 flange is also something i'd like to go with because it works with the mani i already have

 

i would go with the gt28r...

I took my a/c out and i could care less. Living in northern minnesota i rarely need AC. I get by with a rag on those super humid/rainy days.

With the roof-less del sol you really dont need AC !

 

My old setup on 9.5 psi, with the regular 16G, made 191 with a 2" DP.

 

I might be selling my turbo kit so I might have other options...would this be reliable on a stock z6?would a t3 super 60 perform better? I suppose I could go with some tuner toy rods and a budget build

 

A GT28R should be able to do that on a D16.


Some guy put out ~255rwhp on an SR20 at 9.5 psi and some cams to let the engine breathe up top. So I'd say with a bit more boost and less displacement you should be able to do 225rwhp pretty easily.

They'll do 300rwhp at 16.5 psi on an SR20.

 

it is untrue that you "cant use ac with the gt28r"....the way the turbo is mounted depends on how the kit or manifold...was designed...
dont make assumptions and go off what you hear

im running a gt28r on my gsr, with ac and no clearance issues

 

so has anyone used one of these with greddy manifold and a/c? Gotta have cool air out here in florida.

 

I have one on a d-series greddy manifold. I used the cast 18g elbow which is very close to the compressor. You also have to grind on the block a little for the compressor to fit Atp sells a t25 flange that has a seperate 1.5 inch wastegate port and 2.25 inch exhaust port. You might be able to get 2.25 inch piping to work.

http://www.atpturbo.com/Mercha...e=FLS