Second turbo?

[JoeyD]

The VGT turbine was supposed to replace the wastegate but in reality it failed at this task compressor surge became a huge problem when they were first introduced. There has been some unconfirmed speculation that porsche is using a combination of VVT (variable vane technology) turbos and wastegates to achieve super-quick spool up and prevent boost spike and compressor surge.

If, on our cars, super-quick spool up is desired your best bets are to (1) free up the exhaust system with a 70mm to 3inch exhaust system turbo back and (2) to get rid of the stock ECMs control over the wastegate allowing for maximum boost all the time. The KO4 varient used in our cars is capable of spooling very quickly. Also, a good launch will help alleiviate some of the laggy fealing.

 

[psi365]

The VGT turbine was supposed to replace the wastegate but in reality it failed at this task compressor surge became a huge problem when they were first introduced. There has been some unconfirmed speculation that porsche is using a combination of VVT (variable vane technology) turbos and wastegates to achieve super-quick spool up and prevent boost spike and compressor surge. QUOTE]

Not sure what you mean about compressor surge. The VTG is a VVT. Same difference. Neither have an actual wastegate. The vacuum solenoid on the turbo actuates the exhaust vanes. I've read the 997 twin turbo intro book, its a slightly modified system from what Dodge used. I'm on a few different forums were this has come up. The problems with the early VVT's were vacuum leaks cause the car to overboost and so does making the exhaust no restrictive cause it needed back pressure. With using a MAF system and better electronics its a new ball game with that set up. IF you don't believe me I linked a page that shows both the Porshce VTG and the Dodge VNT.

http://www.legacygt.com/forums/showthread.php?t=40599&page=2&highlight=rdx

 

[JoeyD]

Like I said it was about the porsche system speculation. But compressor surge was a huge problem in the older systems. The system controlling the vanes would cease and lock the vanes in the smallest A/R.

 

[jersey_emt]

The Speed6s 2.3L turbo DOHC in-line four pumps out 274 hp @ 5500rpm. Thats a lot of horses for a mid-sized four-door. But roll on the gas and nothing. Goose the revs above 3500 rpm and 280 foot pounds of torque comes on like a fire hose. If Mazda added a second, smaller turbo or figured out how to make this sucker spool-up faster (call Porsche), the Speed6 could shave a half second or more from its 5.4 second sprint to sixty. That's WRX country, and not a bad place to live.

Isn't a 5.4 second 0-60 already well in WRX country?

And doesn't the WRX suffer from a good deal of turbo lag too? (below 3K, nothing...and then it finally starts getting going)

I also thought that the MS6 made a good amount of torque down low.

 

[Renesis8]

The Audi A3, and A4 with 2.0T FSI both have front mounts and don't have problems with turbo lag. Any turbo car you are going to get some, but compared to a lot of cars the 2.0T FSI spools pretty quick.

I believe the 2.0T reaches peak torque at 1800rpm! Thats a 1000rpm earlier than the Mazda 2.3L. I personally think that Audi is ahead of Mazda in DI and engine technology. However, the A3 and A4 isnt pushing the same horsepower as the Mazdaspeed6(a lot less actually), and the displacement is also less on the engine, and I also believe they're using a even smaller turbo(quicker spool!). Not bashing on the A3 or A4, but you gotta account for these factors when comparing both vehicles, Mazda did their best to give us quick spool, and this is indeed what Mazda aimed for with this motor, they have this on their advertisments as well.

 

[psi365]

THey changed turbos cause the turbo on the 2.0T and the exhaust housing and exhaust manifold are one piece so the turbo becomes more of a cartridge. I want to say its close to a KO3, but not 100% sure. THe 2.0T puts out 200hp, with just a chip they push 250hp and the S3 which gets an additional intercooler( I'd have to look in my training books cause they may already have this) is 265hp (it may have a different turbo). As of this moment Audi is up in the air whether or not we'll even seed the S3 in the states. Right now Audi has the 2.0T FSI, 3.2L V6 Fsi,3.6L VR6 FSI, 4.2L V8 Fsi, and 5.2L V10 FSI.

 

[lisevolution]

I've probably seen the same car as you. The one Wagner did. Wagner abandoned the project, and from what I recall when speaking to the owner, it didn't make enough power to beat the MS6.

I don't think it's the same car, I forget which shop here on LI did it, but it belongs to a guy who works at one of my local autoparts stores. I was talking to him about my MSP and he noticed I was driving my girls 6 so he started telling me about his. I thought he was talking s*** till he let me take a look and a ride. Things a monster... wheelspin everywhere, hard as s*** to launch but once it grips forget about it. Off the line the MS6 would get it due to the awd but if you get a good launch this car wins lights out. He blew my MSP away severely!!!

 

[halfshaft5]

I have talked with a guy in the R&D department of Panoz and they have 20 2.3 in their shop... He told me nothing but he knew a lot about the engine and that they are remarkably good engine if set up correctly. All I got out of him is that in a few years you will see numbers out of the engine that will double and even more be put in factory cars. He also said their is a new generation Cosmo 20b in development and that they have finally made a bulletproof rotory under force induction, and he said major PSI on the induction part....
I see it as a good time to bring the RX7 back to the states and drop that rx8 junk and hand Toyota's new supra back to them in a white bag with surrender written all over it... my .02 worth

 

[Renesis8]

I have talked with a guy in the R&D department of Panoz and they have 20 2.3 in their shop... He told me nothing but he knew a lot about the engine and that they are remarkably good engine if set up correctly. All I got out of him is that in a few years you will see numbers out of the engine that will double and even more be put in factory cars. He also said their is a new generation Cosmo 20b in development and that they have finally made a bulletproof rotory under force induction, and he said major PSI on the induction part....
I see it as a good time to bring the RX7 back to the states and drop that rx8 junk and hand Toyota's new supra back to them in a white bag with surrender written all over it... my .02 worth

I hope you're not kidding.... Factory TURBOCHARGED 3 ROTOR?!?!?!?! That is crazy news..... I hope it does turn out to be true... omg i am too sleepy now, but i am gonna PM you with some questions!!! Now I hope I can get to sleep..... you got me excited... BTW, the RX-8 is not junk The technology in the Renesis is a lot more advanced than the 13B-REW in every way.

 

[Da 6]

I've probably seen the same car as you. The one Wagner did. Wagner abandoned the project, and from what I recall when speaking to the owner, it didn't make enough power to beat the MS6.

That was z6speed in nj right?