I have done allot to my Audi 1997 A4 1.8T Quattro. I have done a T3T4 turbo, 35mm external wastage, 440cc fuel injectors, 500hp fuel pump, bigger fuel rail, Link G4 storm computer, 2 1/2" exhaust straight through, Front mount intercooler with 2" piping, Greddy profecB series to boost controller, greddy B.O.V, boosting 16PSI and its got 180KW at the wheels and 320Hp at the flywheel.
I want more power and a better turbo my turbo takes to long to spool up. Its not fully boosting till about 4500 RPM I want a garrett turbo that is duel ball bearing to spool up faster and hopefully get more power. What are the next mods I can do to get more power before doing the internals? I want to do the internals one day but not until it blows up. Would I get allot of power from boring it out to a 2L?

Any suggestions would be good thanks

 

to get to a 2.0 you also have to stroke it. So at that point you are replacing all of the internals anyways... Also I would do the internals before blowing it up... just doesn't seem like a good way to spend your money to fix it after you put a rod through the block. I can't really say on the turbo although the FAQ has some great info on each turbo. However I don't think a GT30 is going to be a fast spooling turbo maybe a little quicker but not fast. Check out the FAQ here in the B5 section plenty of excellent info on turbo's.

 

get the 3071

 

so you havnt done rods yet, but you are looking at a GT35/40? you have some research to do still... 180KW at the wheels, is that an estimation or a dyno?

the largest ball bearing turbo you want to run on stock rods is a GT2871r. and even that is pushing it. and considering your mods, its not just going to bolt on, you will need some other stuff to support the turbo, like an exhaust mani. and 2" IC piping might be a little too small. and new software/injectors/MAF/FRP.

well when it "blows up" it smashes a nice little window thru the cylinder wall out the side of the block. your engine block is worth its weight in scrap metal. theres no fixing it, its new engine time. next time you will do internals first and not have to swap engines later.

 

Not once did you actually state what power level you really want.

A t3t4 isnt working hard if you are only at 320bhp and 16psi. THey dont even wake up until 20+psi. If you dont like the lag, you can either drop down to a .48 housing which will cut off ~400rpms or drop $800 on a DBB chra and it will spool below 4k and make more power/psi due to less drag. If you are running a 50trim, it is good for over 400awhp with the right setup. Its flows the same as a 3071r. Also, you will need to install rods, and no need for a 2L with this setup. You should also increase the IC piping to 2.5" and go with 630cc injectors and tune.

So basically, up the psi then if need be, change the housing, or change the chra. Then if you still need power, you can add in a cams, soon to be released SEM intake manifold, wmi + tune for it.

 

Listen to cincy haha. I would really stick w/ the turbo you got and maybe change a few things like he said. Unless I am a noob to turbo's im guessing he was saying the 800 is to convert to BB? That and a .48 housing like cincy said sounds like a really good plan to me.

 

Here you go.




I am waiting to get a twin scroll setup done that we will be selling as a kit. We plan on having 2 different versions done, one will use a dual internal wg 3071r or 3076r turbo and the other one will use the new Tial 38mm vband wg's. We hope to get this project started in the next few months, just waiting for the new products to come out before the cars can go in to get the manifolds made.



The .48 a/r turbo's are a huge waste of time, yes they spool up very quickly but that small of a a/r is a huge bottle neck. One was tried on a B6 a few years back and the thing couldn't make any real power since the small a/r just cant flow much exhaust. Smallest a/r that should be ran on a A4 1.8t is a .63, some guys have tried runnnig a S256 with a .55 a/r and it even causes a bottle neck with power falling off early.

 

Yes, $800 is for a new chra which is the center section minus the housings.

Mike, you said internal, not external. Also you are talking about small housing and the .78 will be a pretty small housing for the gt30xx that might negate some of the gains which has been shown in evo land. As for the .48, they are good for just above 350fwhp which is more like 330awhp before becoming a restiction. As for the BW, just read a entire 17page thread on srtforums about the s256 and everyone prefers the .55 over the T3 .63 due to its faster spool up and still makes over 400whp on 22psi on their engines stock with piggy tune. There was just a 1.8t on vortex that had that exact turbo and had 25psi by 4200rpms and held his 350wtq till ~7k before it tapered off. This was a stock head, intake manifold, and crappy log manifold. The spool and power is close to a .82 3076r

 

There are 2 A4 owners on AZ that are running the S256 .55 a/r, both are running fully built engines. I drove one of them down the 1/4 mile at Waterfest this year with it pushing 22psi, it could only run 13.5 and that was with water/meth injection. So my experiance with it is more "hands on" then reading.


Yes I did say internal. We are going to be doing a twin scroll 1.8t manifold using the new Garrett 3071/3076 EVO X drop in turbo which has dual internal wg's. That will be 1 version, the other will be completely different using dual external 38mm vband wg's.

 

Sounds like someone needs a better tune if thats all you could manage. Either that, or the rest of the setup is far from ideal. Not to mention i can do that with a stock turbo and street tires.


Not sure about you, but that looks like a nice flat tq curve. Not to mention there is plenty left in it since its still stock above the block.