How big is the Aperture1 in mm's vs the Aperture2? I'm wanting to buy one, but want to know the real difference between them.

 

Does anyone else know how big are both Aperture measurements are?

 

The Aperture I is port matched to the intake manifold which is about 62mm.

The Aperture II is taken to the largest possible bore of around 65mm.

 

Are there any discernable performance differences running the Aperture I vs Aperture II on a stock intake manifold?

 

I would guess no, but I have no evdence to back that up.

My assumption is that the Aperture II is offered under the presumption that other modification to the intake manifold will follow.

If the opening of the manifold is 62mm, port matching the TB to that diameter will flow 62mm worth of air. (if that makes sense)

Having a TB that has an internal diameter of 65mm, bolted to an intake manifold that still only has a 62mm inlet will still only flow 62mm worth of air.

It's nice to have the widest opening possible, but I doubt any noticable gain will be seen unless compare to a ported intake manifold that has a 65mm inlet.

Don't take my elementary knowledge for fact however. Leave it to works to give you the real answer.

 

You would have to bore out the manifold opening to get any positive effects from the Aperture 2 over the Aperture 1. I went through this same dilemma and ended up with the Aperture 1 due to ease of installation and i found a used one at an awsome price.

 

The benefit of an Aperture II over I on a stock intake manifold would be:

1) Even better throttle response (ramp angle)

2) Slightly more flow than the Aperture I (the over all opening area of the Aperture I is less than the intake manifold because of the throttle plate and shaft)