There is somewhat of a big difference between the T5 (high pressure turbo) and the GLT (low pressure turbo). The GLT will has quicker low end/low speed response because the low pressure turbo spools up faster than the high pressure turbo. After about 30 mph or so, the high pressure turbo is in its zone and will respond extremely well. For highway passing and high speed, the high pressure turbo is better as well.<P>The turbo Volvo engines have quite a few differences to them as well. The high pressure turbo engine is 2.3 liters whereas the low pressure and non-turbo engines are 2.4 liters. The high pressure turbo is 2.3 liters because it has thicker cylinder walls necessary for the more extreme temperatures and pressures. It also has forged pistons, sodium filled valves, and different ECU mapping as well.<P>If my memory is correct, the stock boost pressure for the HP engine is 9.6 psi and the stock boost pressure for the LP engine is 6.4 psi. I think that there is a 1.8 second difference to 60 mph between the LP and HP S70 models.<P>IMHO, just adding a 'chip' to the GLT model would be a pretty good idea, because it will give you close to what the T5 does in terms of stock performance. Although, trying to convert a GLT into a real T5 is not really possible unless you use a 2.3-liter engine block. A chip and free-flow exhaust system for the GLT will get you to around 235hp. I hope this helps!<P>-Drew<p>[This message has been edited by InDy (edited 12-12-2001).]