Thought I'd ask Chatgpt

bmw2800cs

bmw2800cs

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AI will undoubtably lead the path to our dystopian future, until then we can ask questions like this one :). Yes it got the stock carbeurator wrong on a 2800cs. Thoughts? How did it do?

Question:
If I put three Weber two barrel DCOE 40MM carburetors in my 71 bmw 2800cs and a more aggresive cam what will my horsepower be?

ChatGPT said:​

If you're putting three two-barrel Weber DCOE 40mm carburetors (total of 6 throttle barrels) on your 1971 BMW 2800CS (E9), and upgrading to a more aggressive cam, you're making serious performance modifications to the engine. Let's break this down and estimate horsepower gains.

​

  • Engine: 2.8L inline-6 (M30)
  • Stock HP: ~170 hp @ 6000 rpm (SAE gross), ~150 hp (DIN net)
  • Induction: Single downdraft Solex 4A1 carburetor (or sometimes Zeniths) - Wrong!
  • Compression: ~9.0:1
  • Very mild camshaft, built for drivability

Your Upgrades:​

1.​

  • Big improvement in airflow and fuel delivery
  • Much more responsive throttle
  • On a healthy M30, this alone can add 20–30 hp, especially with proper jetting and tuning

2.​

  • Higher lift and longer duration = more power at high RPM
  • Depending on the cam, expect another 15–30 hp
  • May sacrifice low-end torque for high-rpm power
 

Estimated Horsepower:​

Here are some ranges depending on how far you go with tuning:
SetupEstimated HP (Net)
Carbs + mild cam190–200 hp
Carbs + aggressive cam + headers200–215 hp
Fully built (head work, high comp, tuning)220–240 hp
Realistically, with triple DCOEs and a good cam on a healthy engine, 200–215 hp is a solid, streetable expectation without needing a full rebuild.

Notes:​

  • Tuning is critical – DCOEs must be correctly jetted for your engine and altitude
  • 40mm chokes are good for a 2.8L, but if you go extreme, you might want 45mm for top-end
  • Drivability: You may lose some smoothness and cold-start ease, but gain big in responsiveness and top-end power
Would you like help picking a camshaft spec or jetting for your Webers?
 
I have been very impressed with the quality of some of the responses I have had from chatGPT. And this on all types of subjects. Especially the new version 5.0.


Of course, it really pays to double check the responses if an important decision hinges upon them. So I often ask "What are your sources for that information?"
 
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Honolulu said:
IIRC there were M30 motors with a single carb and manifold to match, I just don't recall which cars them. Could be E3, E9 or E12.
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I have an M30 with a Quadrajet on a Euro 4-bbl manifold.
 

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Bmachine said:
I have been very impressed with the quality of some of the responses I have had from chatGPT, and this on all types of subject,. Especially the new version 5.0.


Of course, it really pays to double check the responses if an important decisions hinges upon them. So I often ask "What are your sources for that information?"
Click to expand...
I used copilot a bit and it has been helpful to speed up the search for information. I asked it about shops near me that did dynamometer tuning and the results were just AI hallucinations. Either the shops did not exist or were hundreds of miles away. Asking follow-up questions on the topic were also unhelpful.

The technology is good and getting better, but still far from perfect.
 
My daughter (registered to practice law in Hawaii and CA and having a Masters in Library Science) threw all that over when some high school friends asked her to come work with them for Invidia. She edits responses the questions and pictorial presentations that are used to train AI responses. Some of the responses come from persons with a limited knowledge of western history, and less ability with the spoken language. To be fair, my daughter has an undergraduate degree in English, and I'm a grammar nazi, so she slaughters some of the initial responses. It's amusing to hear some of the initial responses.

Myself, I have nothing to do directly with AI other than to note that any question asked on the 'net is met with an AI-generated summary which seems accurate most of the time. As always, if it smells like a turd...
 
When I was in undergraduate and graduate school any "papers" we submitted had to have Primary Sources and Secondary sources.

The "sources" listed above as sources for AI add up to an amazing 261%!!! Must be the New Math that was popular years ago or information overload on steroids. None of these sources are remotely close to qualifying as even Secondary sources in my book. Do you really want to rely on facebook and youtube that don't even know how to capitalize a proper noun for 43% of the information in your AI answer?

We are doomed.
 
CSteve said:
When I was in undergraduate and graduate school any "papers" we submitted had to have Primary Sources and Secondary sources.

The "sources" listed above as sources for AI add up to an amazing 261%!!! Must be the New Math that was popular years ago or information overload on steroids. None of these sources are remotely close to qualifying as even Secondary sources in my book. Do you really want to rely on facebook and youtube that don't even know how to capitalize a proper noun for 43% of the information in your AI answer?

We are doomed.
Click to expand...
Not that bad. If the sources are not mutually exclusive they can add up to more than 100%.
If all answers provide one same Primary Source and another same Secondary Source then the sources add up to 200%.

Where we are doomed is with Sovereign AI.

For instance, India does not want models trained by the West as they reflect a Western view of history and facts, to which they do not subscribe necessarily.
 
Here is the result of my query with my engine mods.
Building a naturally aspirated (NA) M30 engine with 3.5 Weber 38/38 carburetors, 10.5:1 pistons, an aggressive cam, and headers With a complete package like this (high compression pistons, aggressive cam, headers, and Weber carburetors), your 3.5L M30 engine could realistically make around 250-260 horsepower at the crank.

Seat of the pants, it feels like 250 !
 
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