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It's been widely claimed that the stock intake flows more air to #6 cylinder at high boost on big turbos. I've never seen any real evidence to support this notion, so I did some testing the other day with the Heraeus EGT monitoring system to see how EGTs changed from cylinder to cylinder as the boost pressure was raised. I did 9 tests at increasing boost pressures, starting with a steady state 3K RPM cruise and then making 8 pulls between 18 PSI and 28 PSI, recording the peak EGT from each cylinder after each pull. I did the testing on my car with the SP74, RPS header, SP fuel with 720cc injectors, VPC, SFC, FMIC...
At a steady state cruise, all the cylinders appeared to be running at more or less the same EGT. Under boost, cylinders 1 and 3 appeared to be the hottest and cylinders 2 and 6 the coolest, and the differential seemed to increase a bit as the boost pressure was increased. Obviously this does not support the common belief that #6 runs leaner than the rest at high boost.
I'd like to have the time and opportunity to test all of the aftermarket/modified intakes on my car and see how they compare...
Steve
FJO dealer
At a steady state cruise, all the cylinders appeared to be running at more or less the same EGT. Under boost, cylinders 1 and 3 appeared to be the hottest and cylinders 2 and 6 the coolest, and the differential seemed to increase a bit as the boost pressure was increased. Obviously this does not support the common belief that #6 runs leaner than the rest at high boost.
I'd like to have the time and opportunity to test all of the aftermarket/modified intakes on my car and see how they compare...
Steve
FJO dealer