Audi S3 GT3582R stroker Build (previously GT3071r)

[tufftybloke]

Finally!!! AH Fabs managed to find a window in their busy work schedule to crack on with my FMIC...

Just to play catch up as it was some time ago since I fitted my original FMIC...

...this was fitted while I was still on the K04... since then quite a bit has changed and in the search of increased flow and performance I made a few changes to the original FMIC... going from 51mm outlets to 60mm outlets in this case...

...and changing the charge pipe work to suit...

...anyhoo... turns out that I have outgrown my little FMIC in the pursuit of power so needed something bigger especially as I had a bit of a pressure drop problem of around 8psi on spool and a steady 5psi after that...

First of all, big thanks to great mate Mark for his help and support today... much appreciated... and big thanks to Lars and Alex at AH Fabs for understanding my vague instructions and producing yet another fine product...

Started off with Alex sending me the core so I could measure it all up... after removing 4 rows from the original 25 and taking pics and measurements I met up with Lars who knew exactly what I wanted from my ramblings and bingo... one new FMIC complete with 63mm pipe work...

...bit of modding of the crash bar to allow for the extra width of the new core and its brackets... just shaved a little off the bottom to get the brackets flat...

...fitted...

..got the car back to Badger5's workshop and relocated the horns to where the passenger side SMIC used to be by modding the bracket a bit...

...and of course the bumper fits on perfectly....

...still need to paint it black of course but initial feelings from the way the car now drives are promising but has also highlighted that my map really needs tweaking as boost control with the N75 is a little wiggy even with the MBC in place and had a couple of hiccups with a throttle cut on the way back to Bill's...

That does at least mean that I am heading in the right direction as all the boost appears to be getting through now but will of course do some testing next time I get her on the dyno...

Next thing to do is get the Golf MOT'd and taxed so I can change the head... again!!!

<tuffty/>

 

[MrBen2k7]

Looking good mate, now to get it mapped and dyno'd??

 

[Gulfstream]

350bhp at 23psi on a 3071?? Seems to me your about 100bhp short.. And why is your AFR so lean until 4000rpms?

 

[ibizacupra]

30bhp at 23psi on a 3071?? Seems to me your about 100bhp short.. And why is your AFR so lean until 4000rpms?

If you care to actually read the thread fully, you see the previous fmic was choking flow... so instead of getting fixated (like so many others) about boost numbers, better to review overall flow... More flow, more power. There was very large pressure loss across the small fmic, choking flow..... pre intercooler. graph pictured above. measure the boost at the plenum, and whats 23psi there is not supported by flow to suit.. turbo itself is working >32psi and a heat pump.. further hurting any power potential it may have... choked up, spooling too hard, pumping massive heat out.. into an already choked, inefficient (for the gt30) fmic setup.

moral is what works for a k04 will not neccessarily work for a significantly larger unit like gt30


and as for fueling - why would you overfuel it before its spooled? you just hurt spool

 

[tufftybloke]

30bhp at 23psi on a 3071?? Seems to me your about 100bhp short.. And why is your AFR so lean until 4000rpms?

What Bill said and the mapping is not finished yet... plenty of boost pressure but no airflow until now... hopefully...

<tuffty/>

 

[Gulfstream]

If you care to actually read the thread fully, you see the previous fmic was choking flow... so instead of getting fixated (like so many others) about boost numbers, better to review overall flow... More flow, more power. There was very large pressure loss across the small fmic, choking flow..... pre intercooler. graph pictured above. measure the boost at the plenum, and whats 23psi there is not supported by flow to suit.. turbo itself is working >32psi and a heat pump.. further hurting any power potential it may have... choked up, spooling too hard, pumping massive heat out.. into an already choked, inefficient (for the gt30) fmic setup.

moral is what works for a k04 will not neccessarily work for a significantly larger unit like gt30


and as for fueling - why would you overfuel it before its spooled? you just hurt spool

I ran ebay tx 350 core on my setup and dynoed 470bhp, on 2 different dynos at 25-27psi. Same GT3071R turbo, albeit with a billet compressor. Now thats a small fmic. Thats why I thought this setup seemed to be down on power. Now I have a Garret 550 core installed for this seasons trackdays. also need to add I maxed out the MAF when I had it bolted on at 340g/s with the small core as well.

As for the AFR Im comparing to mine, where as soon as I open throttle AFR requested goes to 12-ish and I have 25psi by 3600rpms. Spool is great...

What timing are you running?




Im not fixated on anything simply stating facts mr Bill

 

[ibizacupra]

I ran ebay tx 350 core on my setup and dynoed 470bhp, on 2 different dynos at 25-27psi. Same GT3071R turbo, albeit with a billet compressor. Now thats a small fmic. Thats why I thought this setup seemed to be down on power. Now I have a Garret 550 core installed for this seasons trackdays.

As for the AFR Im comparing to mine, where as soon as I open throttle AFR requested goes to 12-ish and I have 25psi by 3600rpms. Spool is great...

Im not fixated on anything simply stating facts mr Bill

throwing fuel in before its spooled and flowing will hurt spool.. fact

how do you know you have exactly the same turbo? same pipework? same size and construction fmic? nope nope and ... erm nope

the boost profile pre and post intercooler tells the story.. which is why i refer you to the graphs.. I did the tests - lol, and did them for a reason.. The gt30 SHOULD of course make more than this, which is why flow is paramount, and where you see a turbo working 32psi to see a manifold pressure significantly less, you are wasting your time and energy flogging a dead horse.

this larger fmic should deal with the flow/pressure_drop issues seen and logged

25psi by 3600rpm - logs would be nice to see - impressive if real on a std gt3071 (billet wheel comp is'nt a std 3071 anymore tho is it... lol)

i say fixated by boost as thats all YOU and so many others harp on about... the boost pre and post fmic are clear to see on the plots of the smaller core. boost without flow is just pressure with nowhere to go.

we will see what its like when its on the dyno and final mapping can finally be done.

edit: to your edit... 22degrees timing >6krpm under the boost as plotted above.

 

[Gulfstream]

its a Gt3071R right? Same turbo as I have.

here is one of my dyno logs:

and here is the spool with 12.5 ish AFR from around 2000rpms. Will try to lean it out a bit below 3000rpms and advance the timing... see whats happening. 4th gear with Hallmans MBC set to 20psi.

I feel your need for flow. The flow not boost is what I built my car around with AGU engine(bigport) 3" dp 100cell cat no MAF 70mm TB SEM bigport. Only thing I neglected was the core. now thats fixed.

Timing looks ok.

I hope you guys get the power back from this beast

 

[ibizacupra]

there are different flavours of GT3071

you can say "Same GT3071R turbo, albeit with a billet compressor" and think its the same unit can you

T25 internal gated one used..

 

[PhilW]

I'd love to see a "3071" make 450bhp @ 23psi.

I cant make head no tails of that log, but how the hell you can make that pressure by 3600 amazes me. What manifold? Size fmic piperwork and fmic you using?

 

[IbizaAlex]

Is 440 at 1.6 bar (23psi) close enough phil? Indys new MRC map made 405 at the wheels with 25 psi peak and 23 psi hold. 405 at the wheels should be around 440-450 at the fly.

 

[Gulfstream]

there are different flavours of GT3071

you can say "Same GT3071R turbo, albeit with a billet compressor" and think its the same unit can you

T25 internal gated one used..

I dont think its the same, Im telling you its the same. My billet compressor has the same shape as the cast compressor. Its actually a little heavier so it should spool later than the cast one....

But theres the difference.. Im bigport and T3 external 38mm Tial gate.

 

[Gulfstream]

I'd love to see a "3071" make 450bhp @ 23psi.

I cant make head no tails of that log, but how the hell you can make that pressure by 3600 amazes me. What manifold? Size fmic piperwork and fmic you using?

I can do 25psi by 3600rpms all day long no probs. I dont wanna hijack this thread, but you can find my post if you look for it.

pagparts T3 manifold GT3071R billet with .63 ar turbine, 63mm pipes, 70mm TB, SEM bigport intake, MAF less Eurodyne tune, 630cc Injectors, 255 Walbro inline, 3" DP with 100cell cat, oem pipes after cat. Simons turbo muffler. Fmic when I made 470bhp was tx autosport rated 350-375hp. Now I have a Garret 550 core with 63mm pipes.

From what Ive seen, if you run a 3071 turbo and dont see 400whp something could be done better.

 

[PhilW]

Is 440 at 1.6 bar (23psi) close enough phil? Indys new MRC map made 405 at the wheels with 25 psi peak and 23 psi hold. 405 at the wheels should be around 440-450 at the fly.

Inetersting, should be what i make I reckon, 351whp at that boost level with major wheelspin. Wheres peak power and what is he revving to?

I would love to get that kind of spool tho.

 

[ibizacupra]

Is 440 at 1.6 bar (23psi) close enough phil? Indys new MRC map made 405 at the wheels with 25 psi peak and 23 psi hold. 405 at the wheels should be around 440-450 at the fly.

is this the same dyno hooch got his 460bhp

 

[ibizacupra]

I dont think its the same, Im telling you its the same. My billet compressor has the same shape as the cast compressor. Its actually a little heavier so it should spool later than the cast one....

But theres the difference.. Im bigport and T3 external 38mm Tial gate.

billet wheel is'nt same as cast, hub diameters will be different.,.. why fit a billet if same as cast?

internal gate vs external gate
t25 vs t3

apples and pears in spec terms - you cant compare efficiencies of internal gated housings and external ones, nor t25 vs t3...

is yours stock 1781cc or 2ltr?
spool is impressive, and nothing like anything i have seen yet

 

[Gulfstream]

billet wheel is'nt same as cast, hub diameters will be different.,.. why fit a billet if same as cast?

internal gate vs external gate
t25 vs t3

apples and pears in spec terms - you cant compare efficiencies of internal gated housings and external ones, nor t25 vs t3...

is yours stock 1781cc or 2ltr?
spool is impressive, and nothing like anything i have seen yet

I got billet for the longevity. It simply last a couple years more than cast. Why did you go T25 and not T3? And what turbine ar?

Mine is stock AGU motor IE rods, controlled by BAM ecu. If you have a look at the official dyno thread on vwvortex youll find my spool if far from unique.... Im close to optimal spool but Im right where I need to be as far as power goes. Not a dyno lottery. Have gone to two different rollers to confirm the nrs.

 

[ibizacupra]

you are forgetting this is fitted to an S3, which had a transfer box to accomodate, unlike an LCR which is fwd and has no such space constraints.
T25 for what was the choice at the time.

US dyno's read in the main optomistically imho.

and a billet comp wheel is going to be smaller in the hub diameter, so effectively more blade than a cast one. its pointless discussing & comparing as the differences, and significant between the two.

 

[dan.h]

Hi mate, is your car still running the standard pistons?

 

[tufftybloke]

Hi mate, is your car still running the standard pistons?

At the moment yes....

<tuffty/>