J Chen

You mean like me Corleone ? 100-200 kph in 8.3 secs.
Should be able to do better once I dial in the AF with a
better mapped chip.

Corleone

I did mine 100-200 kph at 7,3 now. Next year it will be under 7...

J Chen

If you can do that, I should be the same or better with the
GT25TO4S Corleone. Right now I've got drivebilty issues
lower down the rev range. Hmmm looks like it may be time
to get a Vitesse chip set. Oh, theres a guy here running a K27
turbo in a BMW E36 running 6.2sec from 100-200kph.

J Chen

BTW Corleone, 7.3sec is fast man.

Skunk Workz

Whatever you do Andrew, DON'T go Innovative...

Corleone

Why is that?

Skunk Workz

Fairly simple...when one of your friends have used them and suffered 3 bearing breakdowns in one summer's worth of driving,you wouldn't recommend it to anyone. In 2003 I found that of the people I know running Innovative,every single one have had atleast one bearing failure... Needless to say,they're not running Innovative anymore.

Corleone

I think they now have changed bearingsystem but Im not sure. I asked because I have an Audi 700 hp friend who runs ITS. For him I was asking some of the Audi tuners in Norway and Sweden about what turbo to use and they both said that ITS was very fast spooling, better than Garret and Turbonetics. Looking at their webside you can see that they has some new bearing patented technology that will be released spring 2006.

Im also going for a new turbo now when Im building a new engine and it would be nice to now if there is anyone better than another.

Skunk Workz

Ok,then I see...but I'm staying with the S.P. turbos,they have even better spool than the ITS,no surge problems,and never had any bearing failures that I know of due to their custom in-house bearing design that they've used now for a couple years. Only problem is that they don't make small turbos...yet. But with the spool it has...I won't go small anyway.

Corleone

S.P. Is this Precision? Is there any web site?

What one/size do you have?

J Chen

Corleone : sound-performance.com

NZ951

Thanks for the info guys... Corleone, what RWHP do you think the .63 is good up to?

fast951

Guys, the A/R is just a ratio!! The frame of the turbine housing plays a big role as well. A/R affects spoolup in the same compressor family (T3, T4 etc..). So the AR alone does not dictate how much power the turbine can support, the housing (or housing family) affects this as well. Of course the 3rd element is the turbine wheel.

Skunk Workz

If you don't know the turbine housing radius,the A/R tells you nothing,nil,niente,zero...

Corleone

With the 60/55 mm and A/R .61-63 (HKS .61, Garret .63) wheel I think 500 crank or 450 rwhp is the limit. With the HKS .73 50 hp moore. This if you really have a free flow exhaust, a god cat long back or no cat at all and prefereble the wastegate with its own free pipe all the way to lower backpressure after the turbine. A compressor could only perform like its compressormap if the backpressure isnt the limit.

With a larger turbin wheel, like the 68/62 mm (next size) with a .63 house you probably could have another 50 hp from the .73 house with 60/55 mm wheel. But this is a heavier turbinwheel and will have a slower/later boostbuildup. Many people choose to big turbos, the only that matters is the hp and not the accelerating times!

All of this is just my guessings from what I have learned from my experience but I think its pretty close reality.

I can say if you have 500 crank hp in our cars it is a lot, it is a huge difference than having 350 (which is a lot easier). There has been a lot of inflation in hp talking, how many of us have tried a well tuned 951 with a driveable 500 hp? Its really a lot and its a very fast car. Here in Sweden many talks of their hp´s and when they go to the dyno its often a lot less power than they expected and there is also a lot of dynos that dont are calibrated and makes this even worse. The thing is to have that amount of power that you want with so little in boost as possible and with good timing advance.