2.9ltr Boxster vs Cayman

[Slurms]

When they were launched the Cayman was supposed to have a 10hp advantage over the Boxster but I've been told the engines are functionally identical. 

If so is this just a software setting? Can you liberate 10hp more from the boxster engine with little effort? Or was there some technical change somewhere?

[lawrencequinn]

This link is to the same question in 2020.

 

I have a 2.9 Boxster and I don't think you would notice 10 more bhp. They are brilliant little cars that can use all their performance almost legally. They hold their value well too.

[phazed]

I believe the Caymans had a slightly bigger, throttle body, and therefore slight alteration to the mapping to allow for this.

For instance, I am sure I read that my RS60 has eight BHP more than the standard 3.4 S due to the change to the Cayman throttlebody.

They probably did the same with a 2.9

[Slurms]

On 2/14/2023 at 4:58 PM, lawrencequinn said:

This link is to the same question in 2020.

 

I have a 2.9 Boxster and I don't think you would notice 10 more bhp. They are brilliant little cars that can use all their performance almost legally. They hold their value well too.

Interesting, so it looks like it’s just a map difference then. Same engine but the Cayman is mapped to produce maximum power at 7,200 the boxster at 6,400. 
 

in practical daily driving its not likely you’d notice 10hp but I do wonder if the higher redline provides different characteristics. I’ve never drive a 2.9 cayman to compare with my Boxster only the 3.4s which is a different animal. 

[½cwt]

A bit of limited research.  The DME is the same part numbers on the equivalent Cayman and Boxster variants according the the Porsche PET, so unless they have to be programmed to the vehicle type by the OPC before fitting (possibly? @Richard Hamilton), they are the same, as are MAF, throttle body, induction pipework, injectors and even replacement engine part numbers....   

[Richard Hamilton]

They use the same DME for lots of different models, and program a different fuel map for each when the DME is fitted - either at the factory, or by the dealer.

[Davey P]

I think we are missing the point here... the main thing to take away from all this is that the Cayman is 10 bhp better than the Boxster 

[iborguk]

6 minutes ago, Davey P said:

I think we are missing the point here... the main thing to take away from all this is that the Cayman is 10 bhp better than the Boxster 

You need more vitamin D.

[zcacogp]

3 hours ago, Davey P said:

I think we are missing the point here... the main thing to take away from all this is that the Cayman is 10 bhp better than the Boxster 

A tiny amount. 

But then it's a bit lighter as well, and a bit more aerodynamic, and a LOT stiffer. 

And all those little bits add up. 

[½cwt]

5 hours ago, iborguk said:

You need more vitamin D.

He can't get more vitamin D, the roof doesn't go down so no more Sun, unless he's into eating lots of mushrooms.  Explains a lot actually. 

Although he did have a trip to his local parcel shop to send me something today, so he's a decent enough chap 👍.

[iborguk]

2 minutes ago, ½cwt said:

 

Although he did have a trip to his local parcel shop to send me something today, so he's a decent enough chap 👍.

Hope he threw in the toffee wheel.

[½cwt]

2 minutes ago, iborguk said:

Hope he threw in the toffee wheel.

Not sure, but I don't think so.  No requirement for one currently though.

[iborguk]

Just now, ½cwt said:

Not sure, but I don't think so.  No requirement for one currently though.

Maybe he held onto it to rub a bit more roof off 🙃

[Slurms]

On 2/27/2023 at 12:36 PM, Richard Hamilton said:

They use the same DME for lots of different models, and program a different fuel map for each when the DME is fitted - either at the factory, or by the dealer.

Thanks Richard, so it looks like a different map then, likely explains the advertised gains by some of the aftermarket tuners as they're really only applying a slightly modified Cayman map to the Boxster. 

[horror]

From the small print in the  987.2 Technical Appraisal by Porsche when the cars were first introduced:

. . “Air cleaner
All new Boxster and Cayman models are fitted with the same air cleaner as their previous models.
On the Boxster models only, the size and position of the opening to the Helmholz resonator (H) have been modified at the air cleaner output in the intake area for the intake system. This improves the intake noise, in particular on the "open" Boxster models with minimal intrinsic insulation from the roof construction or when driving with the top down” . . . 

And their you have it for 987.2 models: Caymans are more powerful than Boxsters, Boxsters are noisier than Caymans,

[temporarychicken]

On the 981 with the DFI engine the only difference in the 2.7 boxster map was that the max throttle opening was less than 100 percent as you approached the red line.

From the above the 987.2 2.9 appears to use the same method.

This was a purely artificial limitation to justify the then higher price of the Cayman.

Since the 982 they've reversed the pricing to make the Cayman the cheaper model, so this ECU limitation is no longer used.

A chip tune will get rid of this limitation on a Boxster but it's not going to be night and day.