I have a ported/extrude honed gt40 lower on my car with a set of powerheads. The runners on the lower are 2.10" tall, the powerheads measure 1.94". I had originally planned to taper the runners on the head a little bit to make the transition easier, but the way the powerheads are ported they leave almost no room on the top.. if I took any material off I probably would have gone right through the casting.
When I sat the lower on the heads during the install, I looked through the runners with a flashlight.. they all lined up great except for the tops, there's about a 1/8" wall on the heads exposed.
So the car is together and running now, but I'm wondering if my performance is suffering any because of this. It's obviously causing some turbulence, but I don't know how exactly it's affecting my power, if at all. Do you think I would benefit from a smaller lower? If this piece is robbing power I'll use the stock gt40 manifold.
Thanks!
When I sat the lower on the heads during the install, I looked through the runners with a flashlight.. they all lined up great except for the tops, there's about a 1/8" wall on the heads exposed.
So the car is together and running now, but I'm wondering if my performance is suffering any because of this. It's obviously causing some turbulence, but I don't know how exactly it's affecting my power, if at all. Do you think I would benefit from a smaller lower? If this piece is robbing power I'll use the stock gt40 manifold.
Thanks!