How can a 911 3.4 have so much more HP than a 3.2 Boxster S?

[Jake Raby]

Originally Posted by Bigsmoothlee

Yes, that is correct. I did a full 3.4l conversion, but drilled the mounting bosses in the 3.4 head to attach a 2.7 intake manifold to it. This allowed me to avoid lowering the drivetrain. I drive my car to work every day and the roads here in the Northern NJ/NYC area are atrocious, so lowering the engine 1.5" to accommodate the 3.4 manifold was a risky proposition. One raised manhole cover and bye bye engine!

I want to install the 3.4 manifold with a 987 raised engine cover, do all of them work or is it only the "S"model that has the raised portion for the intake manifold?

That 2.7 intake is killing the potential of that engine. The 2.7 intake is inadequate even for a 2.7 engine.

[jaykay]

Originally Posted by Jake Raby

That 2.7 intake is killing the potential of that engine. The 2.7 intake is inadequate even for a 2.7 engine.

The 3.2 plenums look to be the same size as the 2.7s. They look to be an even smaller volume than the 2.5s....squashed down. The 3.4 plenums look voluminous by comparison...going by pictures. The entrance into the 3.4 plenums are larger too

One has to wonder what the 3.4s would do atop a 3.2