Quote:
Originally Posted by
Dave@ddmworks
...With the GXP, GM did a good job at minimizing lag inherent with all turbos by using a properly sized turbo, a dual scroll set-up, etc. The aftermarket kits that are out there now have not caught up yet and still continue to use older less expensive turbo's which offer great bang for the buck and are hard to beat for all out power to the wheels(except nitrous, but that is a completely different thread), but give up spool time and throttle response as a compromise. When you look at the dyno plots of a GXP vs. aftermarket it is amazing how much faster the turbo comes in on the GXP. If you look at this post: Dyno numbers for RL - Pontiac Solstice Forum you can scroll down and see a dyno of a GXP vs. and aftermarket turbo kit.
Quote:
Originally Posted by
Dave@ddmworks
With your car you will have torque 1000 RPM's sooner than you would have with an aftermarket turbo, pretty impressive, like I said I would have picked the GXP. 
This is the post as it originally appeared.
A couple of notes that are MOST relevant:
Speaking only for the product we sell, we are very proud of the Hahn/Mitsubishi turbochargers we use, and will stand firm on the fact that they are indeed contemporary technology. The low inertia, high-efficiency wheel and housing designs they employ are the most modern available. Mitsubishi turbos are the overwhelming choice of OEM manufacturers of turbocharged cars for these same reasons.
When comparing turbochargers, it is inevitable that a much smaller unit will come on boost sooner. What's not being considered in the depiction above are some very amazing aspects:
a. The Hahn/Mitsubishi turbocharger in our Stage II systems is large enough to support up to 400 HP of airflow, leaving immense upward ceiling for future power upgrades. The stock GXP/RL unit is much smaller, with an effective top end of 300 HP. 33% more power potential is a bunch!
b. This one will floor ya...the Hahn/Mitsubishi turbo shown above, making 30-40 more HP at maximum RPM, is doing it at only 8-9 PSI of boost, compared to the GXP/RL's unit running 15-18 PSI to make...less power!*
We would choose no other turbo for this application, and we base that upon over 30 years of turbo experience using EVERYTHING that's ever been available. This unit is bulletproof, responsive, upgradeable, and best of all...very powerful.
For those who really need a 7000 RPM four-cylinder to pull hard at 2000 RPM, get the GXP. Sure, it will run out of steam 1500 RPM before redline, but you'll get that low-end grunt you want! If, instead, you don't mind your power coming in at 3000, and you'd like it to pull like a banshee all the way to redline, then we have some options for you!
(Pirated Thread Disclaimer: I don't wish to invade the space here, but my company's name and product were being discussed, and this my rebuttal. If anyone would like to further discuss this particular subject, I'd heartily suggest a new thread so as to keep this one on its original tack
).
*
There's more at play here, including the difference in engine size, but the boost pressure vs. power difference are still extremely demonstrative of the capabilities of the larger Hahn/Mitsubishi unit.