[Massive Type IV]

TIV engines have 23% more cooling fins, that means a fan producing 23% less efficiency can still keep the engine plenty cool and does NOT back all the HP up in the shroud.

I 'm almost finished with dyno testing 10 engines with 3 cooling systems each, when I'm finished and provide the researcher with his information I will post some of the findings.....

I'll put it to you this way, every engine had atleast 9:1 , after this I doubt you will be seeing a single 911 shrouded engine leave my shop, it's just not needed, even at 11.5:1 and pump gas!