Supercharging the 2.7 - Opinions

[aussieboxy]

I know there have been many that have supercharged theri 2.5 with favourable results, but what about the 2.7

I understand that the 2.7 has a higher compression ratio. If using the same 2.5 kit what would be the implications of putting it on a 2.7?

Your comments would be appreciated.

Thanks

[rick3000]

I don't think you could put a 2.5L kit on a 2.7L, they make a seperate supercharger kit for the 2.7L engine.

[der Geist]

I talked to the guys at TPC once and one of them told me that the 2.5 kit used a couple of different tubes. They said they could fabricate a 2.7 kit but it would take quite a bit of time. Apparently the 2.7 kit is something they made in a very limited production run. Maybe if there was enough interest they would do another run. I think at the time that they were making kits for the Boxster the majority of people interested owned cars with 2.5 liter motors. Other than the 3 (I think) tubes that were different I think the kit is identical. I am pretty sure that someone who knows their way around superchargers could make it work. The 2.5's compression ratio is 11.0:1 vs the 2.7's 11.3:1 according to the many sources on the internet.

[blinkwatt]

Originally Posted by der Geist

The 2.5's compression ratio is 11.0:1 vs the 2.7's 11.3:1 according to the many sources on the internet.

Let me make sure I'm getting this right. For every 11 units of space in the combustion chamber there is 1 unit left at it's full compression the moment it combustion(relating back to your 2.5L 11.0:1 ratio above)?

[der Geist]

The ratio is calculated by the following formula:

, where

b = cylinder bore (diameter)

s = piston stroke length

V_c = volume of the combustion chamber (including head gasket). This is the minimum volume of the space into which the fuel and air is compressed, prior to ignition. Because of the complex shape of this space, it usually is measured directly rather than calculated.

Ahh...I just couldn't resist that.

Yes, Blinkwatt-you are correct. Higher compression-more HP. Here is the Wikipedia link for anyone who is just dying to know all about compression ratios....

http://en.wikipedia.org/wiki/Compression_ratio

[aussieboxy]

Thanks DR,

I wasn't sure if they were the same kits or not.