Turbo for 1.8T on stock internals

[bobA4]

I have a 2003 A4 Avant Quattro (B6) with a 5-speed manual transmission. It has the APR K04 Turbo kit installed (turbo, ECU, injectors) and a high-flow cat (CTS). The rest of the exhaust is stock.

Of course, I want a little more power from it. I want to stay on stock engine internals.

What turbo do you guys recommend that will be safe on the stock internals? I am leaning towards staying with Garrett for reliability. Looking for an easy bolt-on install. I assume I’ll need a new tune, and likely new injectors.

I did some searching, but the options have seemed to change over the years, so I’m looking for a current recommendation (**putting on newb flamesuit**)

I also see a couple guys selling the old APR Stage 3 kits with GT28RS in the classifieds, considering those as well.

Any advice is greatly appreciated.

[eljay]

GT28RS / GTRS is a safe kit for stock block with close to ~300chp with supporting mods. Frankenturbo has good options as well.
You already have K04 though, so while you will make a little more power with these options, you will loose some driveability. But that's just my take. More knowledgeable folks will chime in.

This thread is still the best on the subject IMO: http://www.audizine.com/forum/showth...rbo-Comparison

[bobA4]

Thanks. Look forward to more opinions.

[Jaywalker]

Thanks. Look forward to more opinions.

So what did you wind up going with? I'm in the same spot right now...lol

[itsmatt33]

gtrs is the biggest i recommend anyone runs before upgrading their internals. Also realize its boost spikes that blow out rods not just power. I have seen a lot more guys blow out a rod on overboosted k04 with aggressive boost spikes than I have on guys making more power on GTRS. Gtrs is the best all around daily turbo and its how the car should have come from the factory.

[9744RR]

GTRS Elim on stock /orig exhaust mani and block and internals and tranny (TIP) since 2007 on ancient REVO software still running strong in 2020.

[ZimbutheMonkey]

Having done 6 different turbo setups on a 1.8T (K03, K04-15,Frankenturbo style hybrid, GTRS elim, 60-1 T3/T4 and finally a Comp Triplex 5556) I would say that of all the ones I had, the GTRS elim was the best comprimise for power, drivability and reliability. You can easily make 300 CHP on stock internals with the right supporting mods and boost onset/ full boost is right where you want it for the most power under the curve.

My GTRS elim would hit 21 PSI right around 3200 RPM at 3500 feet elevation. If you're under 1000 ft elevation that number should probably be closer to 2700 RPM with positive pressure coming in closer to 1800-2000 RPM. So if you're on stock internals with a 7000 RPM redline that gives you a really nice 4000 RPM powerband and great transient response above 3000 RPM. Can't ask for much more than that.

That said, the new Frankenturbos with the mixed flow turbines and inproved Compressor are also a great bet as well. Better boost response, more early torque (and more peak torque than a GTRS elim) and they give a similarly good area under the curve. Can't go wrong with either option really. Plus you could run the Franketurbo on your current mods with very few changes (albeit at a slightly lower power level). Still it would give you a nice power bump while allowing you get the other supporting mods in place.

Unless you get a smoking deal on one (which I doubt given their original eye watering cost) I would stay away from the APR kits as you'll need to redo the exhaust in order to accomodate the Garret turbo discharge flange and there's no advantage power wise to running a T25 flanged GT28RS over an elim style (the turbine volute areas are exactly the same, only the throat areas are different and the larger T25 throat may actually increase your spool time without adding any extra power).

So unless you do all your own exhaust work yourself, it's gonna add a good $500 at least by the time you get someone to fabricate it and install it.

Oh, and I firmy beleive that there are much better tuning alternatives now to the APR stage 3+ tuning. Remeber, those tunes were written years ago. Well before the tuning for these cars was completely figured out and perfected, nor can they be tweaked for your ambient conditions, fuel and other mods like water/meth. So just one more strike against the APR kits IMO.

[2001.8t]

Having done 6 different turbo setups on a 1.8T (K03, K04-15,Frankenturbo style hybrid, GTRS elim, 60-1 T3/T4 and finally a Comp Triplex 5556) I would say that of all the ones I had, the GTRS elim was the best comprimise for power, drivability and reliability. You can easily make 300 CHP on stock internals with the right supporting mods and boost onset/ full boost is right where you want it for the most power under the curve.

My GTRS elim would hit 21 PSI right around 3200 RPM at 3500 feet elevation. If you're under 1000 ft elevation that number should probably be closer to 2700 RPM with positive pressure coming in closer to 1800-2000 RPM. So if you're on stock internals with a 7000 RPM redline that gives you a really nice 4000 RPM powerband and great transient response above 3000 RPM. Can't ask for much more than that.

That said, the new Frankenturbos with the mixed flow turbines and inproved Compressor are also a great bet as well. Better boost response, more early torque (and more peak torque than a GTRS elim) and they give a similarly good area under the curve. Can't go wrong with either option really. Plus you could run the Franketurbo on your current mods with very few changes (albeit at a slightly lower power level). Still it would give you a nice power bump while allowing you get the other supporting mods in place.

Unless you get a smoking deal on one (which I doubt given their original eye watering cost) I would stay away from the APR kits as you'll need to redo the exhaust in order to accomodate the Garret turbo discharge flange and there's no advantage power wise to running a T25 flanged GT28RS over an elim style (the turbine volute areas are exactly the same, only the throat areas are different and the larger T25 throat may actually increase your spool time without adding any extra power).

So unless you do all your own exhaust work yourself, it's gonna add a good $500 at least by the time you get someone to fabricate it and install it.

Oh, and I firmy beleive that there are much better tuning alternatives now to the APR stage 3+ tuning. Remeber, those tunes were written years ago. Well before the tuning for these cars was completely figured out and perfected, nor can they be tweaked for your ambient conditions, fuel and other mods like water/meth. So just one more strike against the APR kits IMO.

Does this all apply to the AWM in B5’s?

[Cybersombosis]

Yes.

[EuroxS4]

300-350chp is the limit on stock internals. The limint factor is the rods. With rods you can hit 400-450whp without issues. After than were talking pistons and so on.