On these turbo's The K16 housings are machined and sleeved with a jug that suits the Garrett 28 turbine wheel. It's actually smaller in diameter than a K16 but flown much more. We will see!

 

If it's a k24 body it should make more. Add inlets to turno and go catless it should make 600 rwhp
If it's a k16 hotside forget it.

 

My buddy Craig (Who actually gave you advice on your gt2 gearbox conversion), was making over 700 crank on these exact turbos. So I have faith in them. They are probably the k16 side.

 

Doesn't he have a28s? If so why did swap.
I think I 100 octane with more boost you can peak a decent number. But a k16 hotside is te limit.
Did he dyno his car did he buy a 700 hp kit. Those are totally 2 different things.
Markski

 

Hes currently running the A28 with an HTA clipped wheel. Hes making around 850-900 at the crank.

I have his old turbos that were on the car when he bought it.

His car dynod in at that 730 crank number, he had extensive mods, they wernt just a kit. I realize that the gt700 kits usually only make about 660 at the crank.

More boost is the next step. I think I can get a little more out of it, but im staying on the safe side.

 

He has the real a28s and probably the 2873s not 71s.
That's what you need if u want 700 on 91 with meth.
Either way the tq is there. Enjoy it but 570 to 580rwhp is more like it.

 

No I'm saying the turbos I bought off him are the gt2871's which he replaced with his cutrent alphas when he upgraded.

 

Looking great!

 

Are these turbos supposed to flow better and make more power compared to 24 billets?

 

Are these Tial A28s?hta?

 

No they're just gt2871r's in a modified k16 housing. If you read a little farther back there are a few more details.

 

These are from before the Alpha housings were avail. Same Dual BB water-cooled CHRA, compressor and turbine wheel as an Alpha 2871 is stuffed into a modified K16 housing instead of the New Tial Stainless housing. From my experience they work pretty similar up to about 700-750hp at the crank if pushed. After that the new stainless Tial housing V3 Alphas seam to push a little more. Some guys have shown 100+ more hp on that turbo. LQQK is making 700 wheel with a 2873 variant and loves it. Orbel is making a monster 850 wheel! Pushing the hot side yes but it depends on what your needs are. 28's feel like a big punchy V8 and have proven to make the power on 996's and 997's many times over.

 

M, I will bet that all things the same with the addition of inlets and cat bypass you will get the 23hp+
...and more tq than your tires will appreciate! Just make sure she's tight!

 

With the testing I have done on my car on the Dyno ,which is around the same HP as him, if those are Large Good 100 cell cats >>>
I would have to say that he wouldn't gain hardly anything in peak HP but will spool a little quicker and make a little more peak TQ and TQ up to the point where the HP crosses over..But ever little bits helps us gearheads to get to our desired numbers.
Just sharing my info ...
Good Luck

 

I would agree usually, but the last owner (who had the exhaust made) had it done by a shop who welded in 4 (2 on each side) cats that were rated for a different amount of power than the car needed. Typically you would use two correctly rated cats, instead of 4 underrated ones. It makes no sense. Each side had two cats welded together into one.