I5 GT Turbos 2871 / 3071 / 3076 / 3082 / 3582

[A80Avant]

yes i understand that,
but the trend is that any turbo bigger than OEM RS2 should be going with new rods.It was not just a suggestion from many(if not all) and as i say the reason for that is the increased torgue on low range.

I just seem to feel that this trend is now slowly changing, and people that want to get a bigger turbo than RS2 are not necesserally needed to change the rods,and not changing them is not a bad thing nor would a map be a whole of a lot different than what a map to a stronger rod car would have.

To make things more obvious:
IF most I5 cars can get a good clear 1.9bar or 2bar on a 2871 or 3071R turbo after 4000rpm, would that be enough to keep the OEM rods in safety as far as torgue is concerned? Would 550Nm of torgue @ 4500rpm for example be adequate on the OEM rods? If so,then i believe that anyone with a stock bottom end could get a turbo like that and have no worries about bending a rod.

However 2 years ago, a statement like that in this forum would have been more or less discouraged as back then these turbos were thought to be spooling clearly and easily from 3000rpm and the fact that they are bigger than the RS2 turbo made all of us think that they could indeed cause problems with rods.

As far as im concerned,im glad i changed the rods anyway as im addicted to power and i want some better turbo now,but all im saying is that someone that has a view of getting one of these turbos i bet it would be safe to indroduce the boost gradually up until 4000rpm and then keep a high boost up to the red line so long as the EGTs permit it. It would be a good and safe result

[Rusty]

Sigh, limiting boost production in low to mid range, a generic map is not going to be as aggressive as a live map with a car running non stock rods.

Sounds like we are in agreement then

What about the issue of surge on 3071 then? 2871 I was aware was a PITA but wasn't aware of 3071 issues.

[denniselbows]

just so i get things straight in my head if a gt2871 or a 3071 cant make high torque at low revs what makes is posible on the rs2 turbo is it the case where the rs2 turbo can make high boost presure but not the flow to surge and where as to get high boost presure on the garretts you have high flow to go with it?

[Jamo]

What do you mean by unchecked? 2+ bar in the midrange? That I can understand and it is an important point. My point was that if you fit an RS2 setup with known chips that work on a stock RS2 then that will be safe on AAN/ABY block based on them being almost the same.

Slightly off topic now... ... getting back on topic tho...

With correct mapping both 2871 and 3071 can be used on stock rods. I spoke to Minhea about it a while ago and he was happy to map a 3071 on stock rods. MidnightblueS2 is running kkk27/29 with stock rods but Mihnea's mapping means that it's safe and has done countless laps of the ring at full pelt . Guess you have to make sure that the mapper knows the score and that it's mapped safe.

Sigh, limiting boost production in low to mid range, a generic map is not going to be as aggressive as a live map with a car running non stock rods.

[Jamo]

If after all this talk about the RS2 turbo making more than 600Nm torgue on low mid range is a fact,then why was it and still is recommended by tuners and others in here that whoever wants to go for the 3071R turbo should change the rods as a precaution?

From what i gather(but i could be wrong) the 3071R cannot make that amount of torgue down low due to surging,so even if the map asked for 2.5bar from 3000rpm,it would surge so much that the rods wouldnt really have any real danger.
So can this be a rough conclusion that someone wanting to go for a 2871 or 3071 is pretty much safe with the OEM rods then?

Besides there is no problem as far as rods are concerned in high rpm anyway. Have seen RS2 engines push 500hwp on a rototest dyno with GT35 and OEM bottom end without any issues...

? basic question, the principle applies to anything in life the closer to a
limit you run the more closer to failure you are.

If you want to eliminate the chances of rod failures then change them to a better spec.

what has been said here is you can run these turbo's close to the oem rod limits

[Rusty]

RS2 turbo unchecked will make over 600-650nm torque in low to mid range.

Notice i'm saying low to mid range.

What do you mean by unchecked? 2+ bar in the midrange? That I can understand and it is an important point. My point was that if you fit an RS2 setup with known chips that work on a stock RS2 then that will be safe on AAN/ABY block based on them being almost the same.

Slightly off topic now... ... getting back on topic tho...

With correct mapping both 2871 and 3071 can be used on stock rods. I spoke to Minhea about it a while ago and he was happy to map a 3071 on stock rods. MidnightblueS2 is running kkk27/29 with stock rods but Mihnea's mapping means that it's safe and has done countless laps of the ring at full pelt . Guess you have to make sure that the mapper knows the score and that it's mapped safe.

[A80Avant]

If after all this talk about the RS2 turbo making more than 600Nm torgue on low mid range is a fact,then why was it and still is recommended by tuners and others in here that whoever wants to go for the 3071R turbo should change the rods as a precaution?

From what i gather(but i could be wrong) the 3071R cannot make that amount of torgue down low due to surging,so even if the map asked for 2.5bar from 3000rpm,it would surge so much that the rods wouldnt really have any real danger.
So can this be a rough conclusion that someone wanting to go for a 2871 or 3071 is pretty much safe with the OEM rods then?

Besides there is no problem as far as rods are concerned in high rpm anyway. Have seen RS2 engines push 500hwp on a rototest dyno with GT35 and OEM bottom end without any issues...

[Jamo]

Wasn't that during mapping and possibly due to spark hop on 3B dizzy, there are plenty of stock engine RS2s running MRC maps with perfectly serviceable engines... this is a different situation to sticking an RS2 setup on an AAN and plugging in some MRC (for example) chips running say 1.7 bar.

RS2 turbo unchecked will make over 600-650nm torque in low to mid range.

Notice i'm saying low to mid range.

[Rusty]

Other way round, RS2 turbo produces more torque than the 2871 & 3071 and will bend rods at low to mid boost. Ask SteveH although I don't think he like me reminding him of the banana effect.

for the Garrett to do that they have to be 2.0 bar and over in boost profile.

Wasn't that during mapping and possibly due to spark hop on 3B dizzy, there are plenty of stock engine RS2s running MRC maps with perfectly serviceable engines... this is a different situation to sticking an RS2 setup on an AAN and plugging in some MRC (for example) chips running say 1.7 bar.

[Jamo]

RS2 is best for stock motor. It won't break the rods as the ADU / AAN / ABY are all the same. Both 2871 and 3071 can be mapped for stock rods too.

Other way round, RS2 turbo produces more torque than the 2871 & 3071 and will bend rods at low to mid boost. Ask SteveH although I don't think he like me reminding him of the banana effect.

for the Garrett to do that they have to be 2.0 bar and over in boost profile.

[Rusty]

I don't know CFM figures, I'm sure someone like Paul would let you know, he's currently playing with an S6 with 2871 on stock internals. There is another thread about alternative options here with some other options from Repo with various trims of CT 350.

[20vQC]

Really?? I'm planning to buy an S6 2.2t as a daily car as soon as I can sell the coupe or break ir in parts... but...as the S6 is a very heavy car, i want that fast spool up, low surge and a power between 360-400bhp with stock rods. I know I'll have to change the EM for the RS2's and a better intercooler and injectors.. but my doubt is on the turbocharger. Andy do you know the max CFM that the aby/adu... breathes??? Just to take a look over the turbo maps.

Cheers!!!

[Rusty]

RS2 is best for stock motor. It won't break the rods as the ADU / AAN / ABY are all the same. Both 2871 and 3071 can be mapped for stock rods too.

[20vQC]

OK and which turbo will fit if I don't want to loose my low rev's torque to avoid my mileage sacrifice BUT wanting a bigger turbo than the K24-7000 for more top end power on STOCK rods? The K24-7000 stops at about 300bhp, the K24-7200 can do 380~400 (if I'm not wrong) but it'll break the rods, the disco potato 2871RS helps to reach ~450bhp, the 3071 will avoid the rod benting but sacrifices a lot the low end torque, right?? Any other turbocharger brands?
So, who knows which is the best turbo for good power, good low end torque and with stock motor???

[K7ERG]

Happy with my GT3071R 0.63 with 1bar and not fully mapped to maximise (Safe map for running in) 335bhp 300lbft (406Nm) @ 1 bar.
Dont think the standard clutch will cope with much more than a bar.

GT3071R 0.63 will hit the numbers you want with some headway once you get bored of 400bhp 400lb/ft. Just my opinion.

If i was going for another GT turbo it would be the GT35R which might still happen when i get around to building the stroker!

Craig