TTurbine

A little more information on their ultimate build

"For such a high power output (1000HP) is the new race electronic management
MS4.4 from Bosch Motorsport necessary!
With the original ECU fitted in the car is maximum 720HP aviable.

The Bosch race ECU MS4.4 is not compatible with the Porsche instruments and
the original ABS.
The solution is,that we have to use the MOTEC system with display,data
recording and the Bosch DTM race ABS.

1.0) Powerconversion 1000HP for 997 GT2
3.9l
Poweroutput: app. 735KW/1000HP @ 7200rpm
Torqueoutput: app. 995NM @ 5700rpm

Powerdatas 3.9l 997 GT2 engine:


MAP 1: @ app. 1.00 (1.15) bar boost app. 588KW/800HP @ 7250rpm and app.
870NM @ 5500rpm
MAP 2: @ app. 1.10 (1.30) bar boost app. 669KW/910HP @ 7200rpm and app.
950NM @ 5700rpm
MAP 3: @ app. 1.20 (1.35) bar boost app. 735KW/1000HP @ 7200rpm and app.
995NM @ 5700rpm

Attention:
1.15 boost ,1.30 boost and 1.35 boost are overboost till app. 5000rpm!!
MAP positions 1 and 2 are free for customer wishes!
MAP position 3 is programmed for max power and max torque!! "


I guess Toby your next stage is just switching the Turbos and throwing in a motec system

TB993tt

+ The Bosch MS 4.4 + the programming + Bosch DTM ABS + traction control system + the inevitable engine refresh bits.... I don't even want to see the price....

What would really hold me back (apart from the obvious $$$$$) is they would be doing away with the factory traction control and stability control stuff, as I mentioned before on the roads and conditions I use the car in one really needs these features with 900+NM from 3000rpm these cars are beasts and pretty dangerous.

I understand this new engine was built firstly for a good customers 996GT2 race car and now they are trying to get it to work for another customers 997GT2 again a mainly track car.....

The beauty of 1000hp at 1.2 bar is the Secans/CTRs would have no problem keeping the IATs down.......

TB993tt

Some 2012 interior makeover shots, GT2RS red Alacantra parts

TTurbine

I am happy to report after i installed the CTR Intercoolers the car does not go into limp mode or throw an overboost fault when i try to bring boost from 2xxx RPMs at 5th gear as compared to the 997.2 ICs

Nordschleife

strong dope in Qatar

R+C

TTurbine

Probably not as strong as the dope in Germany

sharkster

Hah that's pretty wild indeed... The last one we had here a few weeks ago had red headliner too!

TB993tt

I purchased the IPD kit shown in the pic below as all the evidence I saw indicates that this stuff works.

I finally got a response from the Germans that they had tested the plenum on the 700PS/925NM Cargraphic 997tt on the engine dyno and "it lost power"

Bare in mind the Germans do not like to chew the fat on this stuff they just put it on the engine dyno and perform controlled tests and things work or they don't. I suspect that the plenum did/does give more mid range power on road as has been shown in numerous chassis dyno plots but for me zee engine dyno speaketh.



The Y pipe on the other hand was given the green light, not tested but I sent lots of pics and descrption of the sizing etc - so on it went, if nothing else it looks very pretty

911SLOW

Nice.. Strike 2.
I tested the IPD plenum on the GT3 and the dyno said it didn't work as advertised.

Told Cargraphic that they should at least remove the "HP gains" claim from their website.

It looks that they didn't.. and you fell for it..
Difficult times, dropping sales and BS marketing is much needed.


At least RS tuning keeps the flag up, Cargraphic is too busy splitting in two to conquer the world.

pete95zhn

I had to return to this because BW's secrets start finally leak.

Copypaste of an excellent post by Earl3 @ 6SPO:

Stock 997.1 VTG 2277 ETT comp map below. The GT2 and 997.2 have the 2280 ETT wheel in their VTGs and will move ~0.24 m^3/s @ 60% efficiency. The 2280 is similar to the small Mitsu 16g wheel but weighs less and does a touch better at the Porsche-typical 2.4-2.6 PRs. Reminder that compressor maps are only part of the equation and that an engine at a given RPM, VE and density ratio can only use so much air -size your comp wheel appropriately. Anyone know what the GT2RS runs?? (my hunch is the billet ETT 2283)

So I was slightly off in my guess of 66% effiency, 2280ETT is even worse at max. That equals serious heat.

Those Champion/TiAL custom VGT housings with their big cmpressor wheels (68mm exducer / 49.05mm inducer) apparently have an advance in flow & effiency compared to stock BW units.


PS: Toby, I like your finishing touches!

earl3

Here's the 2280:

ScorpionT

The 2280 may be slightly similar to a 16G in one way or another, but overall, no. The 16G is a slightly modified copy of an old Garrett T series compressor wheel, which was replaced by the GT series, and then by the GTX series. Its 30+ years old and as a whole, not very similar to the 2280.

Unless the turbo is used on a steady state diesel (generator, for example) you cant only look at one efficiency rating. The BW turbos are used over a wide range of RPMs and VEs and must be ideal overall, rather than one specific spot. If you compare the Champion vs OE BW compressors, yes, the Champion may have a higher peak efficiency, but that doesnt make it a better compressor. If you are running stock boost levels and an unmodified engine the compressor is likely not ideal. However, when running higher boost it will be operating closer to peak efficiency levels giving the best performance overall.

The specific mass flow rate given (.24m^3/s @ 60% efficiency) is at the limit, and looks like the turbo would be overspeeding at that point. I would need to sit down with a pen and paper, but I would estimate the standard operating range to be across the 70-78% efficiency range. Neither BW or Porsche would pick compressors that are severely out of their optimal efficiency levels, it wouldnt make any sense.

The Tial housing/wheel combinations do allow for higher mass flow rates and very likely peak efficiency levels, but if not paired with the proper engine they can perform poorly and inefficiently.

earl3

I agree they are very different design philosophies but in the end, both maps sit on top of each other suprisingly well, not just the ragged edge -weight not withstanding of course.


Here's the BW billet 2283 wheel, found in many K16 billet upgrades on the 996 side and some of the milder VTG upgrade kits. Awesome little wheel. Note on converting cubic meters/s to kg/s: at 20C, air weighs 1.206 kg/cubic meter -so the 2283 is capable of ~0.30 kg/s at 60% efficiency and ~0.28 kg/s at 70% efficiency (seems like a perfect fit for supplying the GT2RS with enough air for 620hp @ >70% efficiency).




I'm almost certain that the Champion 49/68mm billet upgrade is the HTA68 wheel from forced performance. This is a lot of wheel and glad to see Champion reworking the compressor housings appropriately and not trying to cram it in a stocker.

pete95zhn

This is now going to go to total hijack of this thread -but not completely OT. I made some crude calculations of how much volumetric flow is needed for certain hp. Some US tuner has claimed that a properly tuned 996 turbo's engine produces 9.5 hp / every lbs/min (=0.0058 m3/sec) of air.
Hence
480 hp = 0.1477 m3/ sec / turbo
500 hp = 0.1539 m3/ sec / turbo
530 hp = 0.1631 m3/ sec / turbo
620 hp = 0.1908 m3/ sec / turbo

These flow numbers are transferred to those compressor maps Earl posted. (Thanks about them!) in similarily crude way with max pressure ratio the engine is claimed to run.
If my calcs and assumptions are in the right neighbourhood (What's the real boost pressure GT2 runs?) and compressor maps correct, all versions of 997 turbo are run in a very efficient area of certain compressor wheel. OTH when squeezed they are very likely to go fast to inefficient area.
Based on Earl's guess of that 49/68mm wheel Champion might use I also played with Mitsu's TD06-20G's compressor map which I supposed to be close to that HTA68 wheel, yet inferior. it' quite interesting, already that 20G can produce 0.28 m3/sec, equalling 460 hp / turbo at 2.2 pressue ratio and 70% effiency! Or 0.24 m3/sec @ 2.0 PR / 75% effiency, equalling 390 hp / turbo. And this is taken from compressor map of older design wheel...

18G inducer/exducer: 50.3mm/68mm
20G inducer/exducer: 52.6mm/68mm
68HTA inducer/exducer: 49mm/68mm but with 7 blades

There's a picture of difference between 20G and 68HTA wheel too, latter is quite fancy:



68HTA from front:



CMS 68 from front:



This being the case they can use those turbos at low(er) pressure ratio and optimal effiency than some other solutions crammed to OEM housings. Until the turbine becomes the limit.

TB993tt

I enjoy reading the compressor maps and commentary but I feel this is applying the simplistic tuning mantra which emanates from tuning of other brands where turbos are rated by hp the premise being bolt 'em on and provide fixed boost level, fuelling spark and low back pressure and these will be you maximum hp numbers.....

All the above should be an anathema to tuning modern Porsche turbo engines and in particular VTG engines. The VTG engines were designed to produce maximum torque as low down in the rev range as possible and to provide a new dimension in throttle response all with a variable AR which keeps the turbo in its sweet spot for as much of the rev/load band as possible.

To simply discuss maximum hp out of compressor wheels surely misses the point ?

I have noticed last 12 months or so that any snippets of data and anecdotal evidence is showing that these big compressored VTGs are not spooling until 4000+rpm so whilst they are hitting their marketing goals with big hp claims they are way away from what Porsche intended.

If you read my story here (back at the begining), the first sized compressor used on my engine produced a peak of 728PS (torque 903NM) and the final bigger compressor 734PS (920NM) Now the 728PS was in controlled conditions on the engine dyno and road testing in 30+C heat showed the IATs were making this 728PS unachievable. The bigger compressors were spun at slightly less boost and showed their 734PS on the engine dyno but as I have demonstrated are down to around 700PS on a 25C day due to IATs.

I am attempting to show the complexity of the system which renders the discussion using hp vs compressor air flow numbers moot

On the subject of compressor wheels my tuners claim that they sponsor an engineer who works for the motorsport arm making KKK stuff (probably branded BW now ?) and he developed a line of compressor wheels which they have used in various sizes which they claim to be much better than the BW/KKK stuff, the RST race turbos and 1054PS Alzen 400kph car have the compressor wheels.....

I was a little sceptical to see that 2280 wheel which you guys say is for the GT2 whose compressor map is dated July 2003, this is 10 year old technology - are we sure that info is accurate