The only good thing I can say about my cowl hood is it does not try to come off. That said it worked great with Nitrous but is a power killer for me on my car. Trying to redirect air before going out again. 900Hp should easily run more than 152 MPH @ 2,940. My big engine really shuts down on top end 144 MPH with cowl hood. It pulls great in low gear but in high gear gives up at 8,000 RPM. On chassis dyno we don't have those problems.