cjv, why not just go straight Garretts?

you should know by know that Protomotive can make those suckers spool up FAST... my old T04E's gave boost about as fast as stock K24's. no joke.

Tyson,

I have driven a car with TO4E's. They are outrageous above 4000 rpm's but can't compare to the smaller hot side turbo below 4000 rpm's. Hopefully, the way KA is set up with the NOS activating at 4400 rpm's I'll benefit from the best of both worlds and then some.:) I'll let you know in a week.

1. Have you driven a T04E with Todd's latest programming? I'm pretty sure you haven't because I invested a lot of time and $$$ after I acquired the vehicle with Protomotive in getting the programming right. We finally nailed it a few months before the shootout. I got boost at 2500 rpm and before 3500 I am on full boost. I'd say that's pretty good.

2. For you in particular, I meant something even more efficient, like the water-cooled center section GT-series turbos.

You may disagree with me all you want on this point, but mark my words, your hot side will definitely become your limiting factor if it isn't already. Just you watch... this is the same reason why I do not agree with the Stage 4GT engineering philosophy, the turbos are quite mismatched when you think about it carefully.

So, to each his own, but I'm just trying to save you from dumping more money down the toilet. You are after the 1000hp mark or more and here you are screwing around with puny little turbos. Ask Todd Knighton or any experienced Turbo engine builder who is an ENGINEER and see what they think, and I'm sure you will see I'm not alone in my opinion.

Tyson,

My feeling is this, at what point does the street car become a track car? I can still pass smog and I am very close to the point that it would not be streetable, a point I am not interested in passing. I have water cooled center sections.

I believe the TO4E is running 35/35 impellars?

cjv, you are my hero because you are always pursuing the impossible and I do mean that in a good way. :)

A 1000+ hp 996 Turbo that will pass smog and be a street car? I think you passed that point when you put in that triple adjustable JRZ suspension with metal bushings, etc.

I think you really should research the Garrett GT series. I think you might be impressed.

Do you have external wastegates?

Not sure about the impeller sizes, but I know that it was a custom blend, not just off the shelf... sized by Wilber with help from Innovative Turbos.

No external waste gates. My understanding is they will not pass smog. Actually the NOS is not smog legal either, however it can be turned on and off to pass.

Interesting. Why would it cause the car not to pass smog?

I believe external waste gates were banned in California for street legal purpose a few years ago. In addition, I believe the internal waste gate helps keep the turbo's spooled while going into turns and while shifting.

If this information is not correct, then I'm wrong.

hmmmm... I'm going to look into that... this is the first time I've ever heard of that.

i don't see the internal wastegates as a performance advantage at all. if anything it creates inconsistent boost levels and creates large boost spikes.

like I said before, why is it that almost ALL the big HP turbo cars use externally adjustable wastegates???

If your old turbo wasn't running kats then it wasn't street legal anyway. The waste gates would be incidental.

We had to do alot of work to enlarge the routing and the BOV department. I am not arguing the external waste gates are not easier to install and more efficient is some applications.

well, that's another story... but really it would've run fine with cats with just a slight programming tweak. Maybe I would have lost 50hp max depending on the type of cat used. Then again, maybe not.

I don't believe you would have lost fifty hp. I believe Todd has done an excellent job, but so has Rob considering the parimeters I have given to him that he has had to follow.

Chad,
I can't believe you have been basically running a stock K16 hot side all this time.

99% of the time (this is actually the first I've seen), whenever someone is after more power with a turbo engine, the first thing they do is by a much larger turbo. To say that you are running half of a stock K16 (more or less) is damn impressive.

*thumbs up* ... I'd be scared to see what KA could do with K24s, T04Bs or GT35Rs in terms of peak power, disregarding drivability, "power under the curve" etc...

Frosty,

I said K16 housing....not K16 guts. Huge difference. Again, I am talking K16 shell which has been machined and ported with martinsetic 235 impellers. These impellers cost as much as a set of turbo's by themselves. I am going to a little larger turbo shell. The larger the hot side turbo, the slow the response comparitively. In addition the real power doesn't come on until higher up the rpm range comparitively. :(

Yeps, I'm sticking to K16 hot side. With the zero clearance and the headers that Kevin gave me, the car is really great in terms of minimal lag. As Cort said, "Drove like a big block vette":)