Maybe im missing something?
 

What is the standard by which turbos are rated? The turbolocity kit comes wtih two GT28 turbos which are rated to 350 HP each, now what does that racing mean?

The same GT28 turbos that comes with the turbolocity kit were also used in the twin turbo c5 vette that ran 8.95 at 153.7 and "1100hp"

http://www.lingenfelter.com/images/CF427TT_eprint.pdf

Could somone explain how this is possible?

That was a 427 Engine to begin with... Take 600 HP and add up to another 700 HP and it is possible. But every component must be reworked in the drivetrain.

When they rate it at 350 each, is that additional horsepower on to what you already have? What kind of power could two GT28 turbos put down on a lt1?

Yes, that would be additional power to what you already have. However, if the compression ratio has been reduced to 8.5:1 for boost then the current value N/A wouldn't be very good. Also the turbo cam would not be very streetable for N/A... which depends on backpressure and inlet pressure. Some cams go with 0 overlap and open the intake valve -15* past TDC others with high flowing exhaust look very similar to blower cams. There are a lot of variences within turbo cam design.

Keep in mind, as soon as boost is applied, it has a dramatic effect on static Compression Ratios. A turbo at 1# would fill each cylinder and overcome the limitations of 8.5:1. Each additional # is more pressure in the cylinder to add power.

But a 427 has tons of potential power. Add two 350 HP turbos and 1100 is not that unobtainable.

Just like with any opther part you may buy for a car that is a general statement. A CAI may give you 5 hp but it may only give me 3 hp. It depends on the setup of the car and a ton of other things.

Michael

I havn't seen a GT28 compressor map, but if they are only rated at 35lb/min each than a pair of them will be maxed out at 700 crankshaft HP. (And that is total, you don't add the turbos HP capability to the engines naturally aspirated hp figure)

I suppose they could make a bit more but they would be way out of their efficiency range.

Also, in that Lingenfelter article, they said they used the GT28 turbos for there 750hp engine, and then they stepped up to larger GT30 turbos. (I have not seen a compressor map for that turbo either).

I have to disagree. I don't think you can take a small turbo, example: like whats on a motor cycle with a max cfm flow of 300, and put it on a low compression, 400ci, splayed valve head, turbo cam engine and add an extra 400HP.

Sorry for the above post. I didn't see INTMD8 post before I posted my response.

Wow! I can admit when I'm wrong. I learned something new... I was under the impression that it was additional to the engine.