If you like vtg , champion motosport did a gt2 3.8 build engine with 68mm vtg , they hit 830 whp I think.
I am no expert but I have read here before that vtg also produce to much heat and also their spool is similar to gt30 which can produce more hp than vtg .
If you want a reliable 997 without a build engine on tiptronic you have :P800 , alpha 9 , es850
The best tiptronic kit is from esmotor and its very cheap if you ask me , it only cost 5500 $ , it shifts very fast and handles more than 1000 hp without any problem .
Building your engine is another story than...

 

I think VTG's would be the best option for you, unless you're willing to spend a lot of money.

Besides the EBC, with other turbos you need BOV's.
Because of your intake, you don't have space to weld BOV's in the Y pipe (you need something like the AMS Y pipe were you put the BOV's in the silicone hoses) or you could put them in the I/C's but you would need another set of I/C's (or make make aluminum end tanks for the GT2RS I/C's so you can weld the BOV's)

Or you could wait a year and I'll sell you my A3071 turbos, Y pipe and BOV's for about the same price as the 68mm VTG's... I want more power

Keep in mind that torque is what kills rods. Whatever you do, torque will be limited by the tune until you rebuild the engine and the tiptronic. Even with that, torque is limited to 1250NM

I'm no expert but I've been reading a lot... 2 years ago I didn't know anything about this... Still not sure if I really do

 

Thanks alot for that info. That is what i was talking about the need to put all that stuff into your car just to have a marginal gain over a 68mm vtg setup on just 98ron pump gas. I know that when you turn on the meth is at a much higher league but i think that with the need of a meth system you lost the daily/trip car factor that Porsche wanted to keep in a sports car.

I don't want to deal with meth systems or special fuels, other than just pump 98ron (93aki). So torque limits will be hard to achieve due to fuel quality. So with the fuel being the main restriction factor, i believe that a 68mm vtg setup would give me +50nm than your setup on just pump mode and still will be below stock rods limit.

 

You only need meth inj. if you want to go into high boost, on both setups.
Other option is race fuel. Around 300€ per 60L tank in Portugal

On my set up I just need to turn meth and EBC on and I'm ready to race. (I daily drive @ 1bar, no meth.)
On VTG's it would be better to have 2 maps. 1 to race and another for daily driving., with lower boost.

Send an email to Emre, he will explain everything and tell you what power and times every kit makes.

 

I want to chime in to clarify a few things;

I have some garret based cars spool significantly faster than VTG equipped cars.

Have you been in an 68mm VTG powered car? If you compare it with Rui's car i bet it will spool slower.

The problem with vtg's is the HOT side, even if you put 72mm compressor wheel on VTG, it will have even more lag, because hotside and compressor side wheels became unbalanced in terms of size. Hotside creates big amount of back pressure.

I'm a supporter of GT based turbo setups, i have been driving them for over 5 years now,
i dont see any point going with VTG's while you are being octane limited.

VTG's need very good cooling and very high flow exhaust system to run optimally.

You are saying that you dont want meth or race fuel, so you are even more limiting your power output with VTG's. (Difference between 63mm and 68mm VTG becomes even smaller)

As Rui said, send me an email to discusss further as i have tested/tuned nearly all turbochargers in the market since 2008

 

Emre, what combination of bore and stroke did you use to arrive at your 4.1L's?

 

Chad,

i will send you email about that.

cheers

 

UPDATE: NEW RESULTS


100-200km/h in 2.80sec

60-130mph in 3.29sec

100-150mph in 3.11sec


Testing and tuning continues, hope to improve it further soon

 

Congrats

0.02s less and the record is yours

 

Go emre, go!!!!!

 

Few issues back there was an interview in Excellence magazine, where some of Porsche's engineers commented the new 991 turbo. He stated that while the hotside has been kept the same as in previous models, the upper limit is around 600hp. Of course he's talking about level of tuning where factory can still provide warranty and there must be some safety factor. Yet against this when someone is claiming 800hp at wheels with OEM hotside I'd be very cautious. At least I'd want to see some backbressure vs boost pressure graphs....

I'll check facts about this interview when I get back home from St Petersburg. The original one, not in Florida...

 

That's ridiculous Emre, Congrats! The record is almost yours. Very soon

 

Emre I think the record is yours, because the EVOMS car is a RACE CAR, without interior carpets, plexiglass windows, on drag tires and run with race gas.

Yours is a STREET CAR, run with all interior, on street tires and go with pump gas.

I think if you go like race car, you brake all records!!

I'm proud to have yours kit on my car!!! and i hope to brake all records for 3.8 with your help.

Thanks for all my friend...

 

Besides being a street car, from what I've read, Salih did the 3.29s with a passenger

 

I hope and don't think that will be necessary