I am in the mist of a diy turbo project and I am looking at the blow thru meters. they have a 3" and a 3.5" pro flow. I am looking at the 3.5" only to upsize the turbo in the future. I will be running around 8psi after the intercooler if all my calcs are correct. my pipe size is 2.5 but I would couple up and couple down at the meter. My question is with 3.5" meter will it read corrctly or should I stick with a smaller one. A friend of mine is giving me a good deal on the 3.5" but before I make a decision I figured I would ask around. the motor is a 306 HCI with a c4 tranny. 87 notchback. 70mm t body.