At first I thought the 8474 would have a compressor that was too large for a 200 six operating at 7500 to 8000 rpm but I see that it is a hybrid based on the smaller 8374.fast64ranchero:1rqpbl9u said:Turbo choice is a EFR black series 8474. Unsure on what EFI will be used, I may start with Holley sniper to get it running.
You may lose a little spool time response but the higher rpm flow is greatly improved over the 8374.
The 8474 is used by the racers pushing 900 hp and need a fast response.
Here is the 8474 map superimposed over the 8374 map.
The red line is the load line for the 200 six operating between 3500 rpm and 7500 rpm at 20lbs of boost with an engine VE of 95% trailing off to 88% with a 60% intercooler efficiency.
Notice that the engine would never be able to use the extended region of the map for the EFR 8474.
It would require the engine to operate near 10K rpm to get there.
Also consider there is less margin to the left at the surge region for the 8474 versus the 8374.
The Holley HP would be a good choice for port injection.
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