Thank you for doing this eye opener Jeff, adds another nice story to tell about our 981. Mid engine dynamics is a plus.
Do you know the cam lift between 911 and 981 and if the throttle body of 991 will fit in 981? If they have same part number and that answers my first question. Tks.

 

The two engines I compared are the MA 1.23 (Boxster/Cayman) and the MA 1.04 (911). Both have the same camshafts and lifters, so the valve lift would be the same. The throttle bodies are a different size and mate to the intake plenums of different sizes simply because it needs to bolt to a different sized throttle body.

I don't know if there are any other significant differences to the intake manifold, but I would suspect not. Would it fit? You would have to do some mods to the rubber Y piece that joins to the throttle body so that if fit OK, but doing this and putting the 911 code in the DME might work, but then there is a bunch of other stuff that talks to the DME, so it might get a little complicated. Not insurmountable problems for an experienced tuner I wouldn't think.

 

That is a remarkable video, many thanks. My only comment is I can't hear it well enough to enjoy it, is anyone else having that same experience?

 

Try ear buds

 

People have been putting 911 engines in Boxster since 2000
911 is a fat Boxster/Cayman given more hp and better parts for the last 24 years
Porsche is finally allowing the B/C's to get the best parts and guess what - they kick 911's butt.

 

I think my first clue was when I noticed that practically every part # I saw on the 981 began with a "991-" prefix. It's practically the same damn car, just with a few parts rearranged. The biggest differences are in the marketing.

911 Carrera = very expensive way to buy two back seats for children, grocery bags, and small household pets.

 

I agree with the above and this was the reason I bought a 981 cayman. Believing it’s the better car. But a 991 is also very nice. It’s a more all around car and honestly it is great fun with the engine in the rear. It has a different feel which is fun. I love the cayman rotation, the smaller size and lighter weight.

 

But not the 50k more it costs

 

Totally agree. The 911 is a big premium. And the new ones are all turbos other than the GT3. I prefer NA.

 

Well isn't this interesting. I obviously knew there was parts sharing, but not to this extent.

What a fantastic video!

 

Refer photo, if B plenum has larger inner diameter than A throttle body, there is probably some HP to be gained with or without tuning?

 

Refer photo, if B plenum has larger inner diameter than A throttle body, there is probably some HP to be gained with or without tuning?

View attachment 293116

Ed - can you please try editing your posting and seeing if you can embed the image you intended to show? It appears there may have been, or still is, an issue uploading photos for display in threads. I was able to do it and display a photo,l but more than one user had the same issue you did above in your posting.

Please get back to me with the results...

 

Great video, thanks!

 

Don,
I changed my first uploaded photo in thumbnail format and made it as attachment only now.

 

The 981 MA1.22 & MA1.23 engines have 2 types of resonance tubes but use only 1 throttle body.

 

I'm just seeing some spam-like links...

 

Fora is having an issue system wide - effecting thousands of websites. Pictures aren't making it. Hopefully this will be cleared up soon.

 

@jjrichar , Jeff if you have a 981 base and S in your garage, is the neck of the intake plenum (where the throttle body is attached) have the same diameter? Based on parts catalogue, it looks like throttle body part# 997-605-115-01 is a common to all 981 & 997 but the intake plenum is different on 981 with MA1.22 and MA1.23. I wonder if one has different diameter to reduce HP of the base by restricting air. The photo of post #15 shows the part numbers.

 

From what I can see the throttles are the same, which means the necks where they join are the same. The big difference in the intake plenums is because the base doesn't have variable geometry, but the S does. So when looking at the parts list you see there are a bunch of parts like the bellows and solenoid that are for this, and so only fitted to the S. When looking at the S plenum tubes, the one that is furthest from the throttle has a big flapper valve in it that is activated by the bellows.

Link here to video that shows this. Starts at the right time.

 

Thanks.

 

I am actually surprised that many folks are surprised that the two cars are mostly common parts.

It is the only reason Porsche still exists.

 

It’s the price differential for a 911 that has the same parts of a cayman. What are you actually paying for?

 

An excellent video, like the rest of your videos.
I think we all knew the 996 and the 986 were almost completely the same cars. But I don't think most realized that never really changed through the 991/981.

 

Useless rear seats
Engine in the wrong place
More HP
60 YEARS OF THE LEGEND.

Useless rear seats
Engine in the wrong place
More HP
60 YEARS OF THE LEGEND.

It’s the price differential for a 911 that has the same parts of a cayman. What are you actually paying for?

As for the price diff, Jeff correctly points out that the Porsche marketing machine has a lot to do with that. I also believe that people buy cars as much for status and image as for anything else -- and the 911 has the super-cool image.

 

Great video, I enjoyed it and it honestly surprised me. If you had to guess, what % of parts are shared between a 981 S and 991.1 C2?

 

It's hard to tease apart, but my best guess is about 90%. Someone did a PDF comparison of the 991 vs 981 parts as well as all the non 991/981 parts that are generic parts like clips, bolts, control units etc that have a different part number prefix. It seemed to suggest this was close.

 

What are you thoughts about engine binning aftet produciton. Binning process is something that is done in many industries which have non-deterministic production outcomes.

Porsche puts the same engine in few different vehicles (Boxster S, Boxster GTS, Cayman S, Cayman GTS, Carrera base), as mentioned in the video, but with very different power outputs. It would make sense for Porsche to categorise those engines after production, and those that are measured as lowest performers put in Boxster S and highes performers in Carrera and GTSs etc.

For example - in graphics card production. Graphic chips are sorted after production to different categories, and different software is added based on categorisation. Final products are different graphic cards even though they are based on the same chip.

This looks a lot like Porsche 9x1 lineup.

 

What are you thoughts about engine binning aftet produciton. Binning process is something that is done in many industries which have non-deterministic production outcomes.

Porsche puts the same engine in few different vehicles (Boxster S, Boxster GTS, Cayman S, Cayman GTS, Carrera base), as mentioned in the video, but with very different power outputs. It would make sense for Porsche to categorise those engines after production, and those that are measured as lowest performers put in Boxster S and highes performers in Carrera and GTSs etc.

For example - in graphics card production. Graphic chips are sorted after production to different categories, and different software is added based on categorisation. Final products are different graphic cards even though they are based on the same chip.

This looks a lot like Porsche 9x1 lineup.

From what I can see I don't think this is happening. Each engine at initial build is made for one car type. Whilst all the internals are identical, there are some differences on the outside, such as the placement of the oil filter housing, belt idle pulley size and exhaust. You can see this in the few snips I took of the engine production line and was the thing that showed me the engines were all produced in the same place.

If binning was occurring, there would need to be significant disassembly after testing to make it for another car type.

There might be binning prior to production of component tolerances etc, but they are all identical part numbers, so I would make the assumption this isn't happening.

 

I suspect at Porsche, an engine is married to a specific vehicle (VIN) before 2 pieces of it are put together.

 

It wouldn't be very Germanic to bin the engines, but then it's not very Germanic to create a temperature gauge that intentionally lies to you, so... (shrug)

 

You don't believe everyone's water temp is 194? lol.