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View Full Version : Yet another question about the GT28rs



samx
05-12-2005, 08:02 AM
Hi,

As you can see, I don't post much but I do read on a daily basis.

I have a question about the GT28RS that I'm hoping some of you guys might be able to help me with.

First, some background info:
I have a 99 A4 Avant w/ a PES T28 kit, Southbend stg3 clutch, and 3" custom exhaust. I'm from the Minneapolis area and know A4robm and Burntaudi.

I've noticed that ATP is selling the GT28RS with an optional GT28R compressor housing. My question is, can I run this turbo in place of my T28?

I'm assuming that the PES intake will bolt up to the turbo, and that the tubine inlet flange will fit to the PES manifold. Being as that I'd still be using the PES MAF, will the programming be able to compensate for the additional air flow? (I'm runnning Bosch green top injectors) I'm sure that the intake will be a bit of a restriction for this turbo, but will it be by much?

It also looks like the GT28RS tubrine housing sits a little lower than the T28, but I think that there is enough clearance between the engine and the frame to accomodate the bigger turbo. I'm also expecting that I will have to get the DP redone.

I know that this will probably not run as well as a kit that is designed around this turbo. But, am I completely off base here? Is there a major issue that I'm not considering?

I'd like this to be an open discussion, so any input you guys have would be appreciated.


ATP GT28RS
http://www.atpturbo.com/Merchant2/graphics/00000001/Catalog%20Images/Turbochargers/GT28RS-375375.jpg
GT28R housing option

http://www.atpturbo.com/root/releases/images/release022105/03.jpg

bitterchild
05-12-2005, 12:33 PM
Theres been a bit of discussion about the actual effectiveness of a gt28rs in a gt28r housing. The end result is little extra flow b/c the inlet of the rs is what allows much of the flow over the r. Stuffing the guts into a r housing doesn't give you the same potential. I can't remember too much but that was the gist of it. Try searching here or aw for it. The regulars were bashing it pretty hard.

skene
05-12-2005, 12:52 PM
I've noticed that ATP is selling the GT28RS with an optional GT28R compressor housing. My question is, can I run this turbo in place of my T28?[/b]

No you cannot there are differences in sizes between the 2 turbos. A new downpipe and intake will need to be fabricated. The turbo will also not bolt up to the exhaust manifold as the GT28RS would need to be moved back because of clearance issues.

I'm assuming that the PES intake will bolt up to the turbo, and that the tubine inlet flange will fit to the PES manifold. Being as that I'd still be using the PES MAF, will the programming be able to compensate for the additional air flow? (I'm runnning Bosch green top injectors) I'm sure that the intake will be a bit of a restriction for this turbo, but will it be by much?

Once again I referenced my points.

It also looks like the GT28RS tubrine housing sits a little lower than the T28, but I think that there is enough clearance between the engine and the frame to accomodate the bigger turbo. I'm also expecting that I will have to get the DP redone.

Once again....

I know that this will probably not run as well as a kit that is designed around this turbo. But, am I completely off base here? Is there a major issue that I'm not considering?

It will not run correctly as everything will need to be modified in the sense of air/fuel delivery. Sure it will run, how well is a whole different story.