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Very curious to see how the new manifold plays out.

Is it possible you're running beyond the efficiency of the turbo, i.e. more PSI doesn't equal more air mass?

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Peace, Ron

Hi Ron. Good thought. However, the excessive richness begins in the 7-9 psi range and the pressure ratio and corrected compressor flow rate on the Garrett map for this turbo place it right in the 77% zone and at 14 psi it's still within the 68% zone. But, thanks for the suggestion. If the problem persists, I'll put the EFR from the RX7 engine on it to see what that does. The map for the Garrett is actually broader in this area than the EFR map.

Ron

Beautiful build. I'm almost sad it doesn't have a passenger seat for ride alongs.

Yesterday the car had its first outing with the different manifold and throttle body. To be safe, I put back most of the fuel metering reductions that had been removed last year trying to raise the AFR's. It ran better, but showed 9's above 9 psi. So, for the afternoon runs the cells at 9 psi plus were reduced a few percent. That resulted in the "too rich" zone moving up to above 10 psi. That area will be changed a few percent more for the next event.
Also, a Windslayer sock was placed on the GoPro and the result was a complete removal of the offending noise.
Now the driver needs to knock off the winter rust. Only one small lockup in the finish "traction circle" of my last run:

https://youtu.be/VW9-OBpbNjA

Additional leaning of the VE cells above 10 psi resulted in much better engine performance at the autocross yesterday:

https://youtu.be/NLuGvfWs8xc

Assuming this is gasoline, if you're running 9's and you wanted to run 11's (for example) it would take more than just a few percent. It's roughly 8% per point, so it would take about a 16% reduction to get to 11's (assuming same decimal point i.e 9.5 to 11.5)

Sounds like you're making nice progress. Is the thought still that the original manifold was the choke?

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Peace, Ron

RTz,
Thanks for the "rule of thumb". Yes, that's what I'm thinking.

My son made a nosecone badge for my car on his 3D printer. Since I refer to this car as "LC2", that's what is above the "LOCOST" in the emblem.
The "2" has a break in the middle of it. I'll have to see if I can touch it up with some silver paint so that it's easier to distinguish.