TB993tt

Mike
Many thanks for the clarification - from this graph, your units look very impressive indeed especially baring in mind the increased boost of the 700S at low revs !

Looking at the stock GT2 boost curve versus the IAT curve it seems that they have held the boost back until 5000rpm when it ramps up to the 1.4 bar level where it stays to the limiter - it is at these higher revs 5000+ that the expansion manifold is supposed to be working its cooling magic (below 5000rpm it has no effect AFAIU) - like you say, imagine the IATs with stock I/Cs and no expansion cooling effect

Really looking forward to more charts, particularly an intercooler one back to back on stock boost programming - please

Gene
Thanks for the report, how did you find the clutch on the GT2 (suitability for daily traffic ?)

eclou

Toby the GT2 clutch was not as stiff as I remembered in my GT3. I think you would get used to it but the disparity between the 993GT and the 997GT2 is what will make it irritating. I think your idea of retrofitting the hydraulics would be very useful. After a drive in the Gt3 I would get into the TT and drive the clutch pedal thru the floorboard on accident....

TB993tt

Gene
I will be investigating the feesibility of that retrofit - I have a dodgey left leg (sciatic nerve damage stuff ) which makes the clutch thing a pain (literally) - the Carrera GT gave be lower back ache for 200 mile+ drives

Mike
Can you weigh the stock exhaust and intercooler units and give the comparable weights for your stuff please ? TIA

eclou

Toby the Gt2 rides pretty rough like the Gt3. Even on the normal suspension setting it tends to feel like you are riding off-road when on anything but glass pavement. Mind you, it is not jarring but I always could feel every piece of gravel or expansion joint on the road. Have you gotten to ride in one to make sure your back would tolerate it?

TB993tt

Hi gene
bit O/t so I have PMed you

Mike/A.W.E.

Updates shortly.

We are compiling more data.

Mike/A.W.E.

We have some headers, software, and intercooler data about to be posted. Stay tuned.

For now here are some additional pictures:

Apex GT

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Looking at the stock GT2 boost curve versus the IAT curve it seems that they have held the boost back until 5000rpm when it ramps up to the 1.4 bar level where it stays to the limiter - it is at these higher revs 5000+ that the expansion manifold is supposed to be working its cooling magic (below 5000rpm it has no effect AFAIU) - like you say, imagine the IATs with stock I/Cs and no expansion cooling effect

I tracked a new GT2 and the first thing I noticed was the hammer coming down at 5000 rpm and before you now it the rev limiter ! This mod should make it even more appealing. Oh Ya, what a feeling!!

sharkster

Toby you should check with a bunch of the 996TT guys with bigger HP kits because many of them have ditched the hydraulic assist in favor of a gt2 slave etc... conversion so there should be a nice amount of free or cheap parts available to try stuff with... Having driven the 997GT2 on that Excellence Mag shindig back to back with my RS I don't think it's significantly stiffer in terms of the pedal feel. It likely uses a Sachs motorsport PP just the like 996GT2 before it and that would be the only part that makes the pedal any harder to push. If I had to put it in percentage terms I'd say "maybe 10%" stiffer. Suspension is quite different to the RS/GT3 in that it's got more of a "glide-like" supple feel. There's certainly less movement/feel and rebound and over bumpy roads it's more "comfy".

TB993tt

Many thanks for the information. I guess I will have to try and live with the clutch for a while before I know whether I "need" the hydraulics....

Mike/A.W.E.

Here is some further info for everyone to digest.

Comparing all our parts individually on stock software.
Our muffler added 12whp/30wtq vs stock (13 crank hp/ 33 crank tq)
Our muffler/headers/intercoolers added 29whp/41wtq vs stock (32 crank hp/ 45 crank tq)




Comparing GIAC to stock, and GIAC + our muffler to stock
GIAC alone added 38whp/19wtq vs stock (41 crank hp/ 21 crank tq)
GIAC + our mufflers added 57whp/60wtq vs stock (62 crank hp/ 65 crank tq)




Comparing all our parts individually on GIAC software.
Our headers added 9whp/12wtq vs GIAC + muffler (10 crank hp/ 13 crank tq)
Our headers and intercoolers added 29whp/22wtq vs GIAC + muffler (32 crank hp/ 24 crank tq)




Comparing all out parts with GIAC vs stock software
GIAC + muffler/headers/intercoolers added 57whp/41wtq vs stock software + muffler/headers/intercoolers (62 crank hp/ 49 crank tq)




Comparing GIAC + AWE vs all stock
GIAC + muffler/headers/intercoolers added 86whp/82wtq vs all stock (94 crank hp/ 89 crank tq)

eclou

nice work Mike. It looks like the intercoolers provide the biggest delta over 5700 rpm when the intake charge is at the highest risk for heat introduction

TB993tt

I don't like chassis dynos being used to tune Porsche turbo engines. I have seen too many bad jobs in the past and they usually revolve around the fact that the chassis dyno cannot/does not load the engine enough during the tuning phase and consequently a nice looking power run graph does not translate as such in 6th gear under full load in certain atmospheric conditions.....

Below is an RS Tuning engine dyno full load diagram for their ecu/exhaust GT2 package.
Note how the engine is fully loaded enough to generate full boost by 3000rpm ?

The Mustang does not appear to do this with peak torque not being achieved until 4800rpm which is nonsense for a VTG engine.... (note even in stock form the peak torque on the Mustang is not until ~4800rpm)

Further if there is insufficient loading (by the chassis dyno) to generate the boost/torque at where it will/should actually occur on the road ie at around 3000rpm then the surely the whole heat IAT "curve" will be wrong so does this negate the whole power run ?

Trying not to be negative here guys, what am I missing ?

eclou

good point Toby. I think the main limitation is that a typical chassis dyno run will be in 4th gear, but even on the street I don't think the 997tt can generate full boost by the advertised 1950 rpm in 4th either. So then would it be fair to contend that the chassis dynos are accurate for 4th gear and less accurate for the loads encountered at 5th and 6th? I would entertain this would explain why the Switzer car does as anticipated up to ~150mph but after that we see the ugly faults arise.

ehall

It's a good thing that you guys at AWE are adding all of this power to an otherwise anemic automobile!
Holy Crap!

Interesting discussion vis a vis dyno vs. real road data. It will be really cool to see the numbers, once this car hits the road.

Either way, I wouldn't kick it outta the rack!