RX7Club.com - Mazda RX7 Forum - Eurospec 5,6th ports don't use rotating sleeves? What gives?

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Eurospec 5,6th ports don't use rotating sleeves? What gives?

Just cruising threads looking for info on 5th, 6th port dynamics (specifically cutback) and came across a thread stating that european 5th,6th ports use butterfly valves and not rotating sleeves?

Does anyone know why / what gains, loses the butterfly system offers or did I just read the thread wrong? thanks ~rich

i thought euro/japan were the same

Quote:

Originally Posted by alexdimen

i thought euro/japan were the same

Japan did not have non-turbos.

-Ted

Quote:

Originally Posted by n/a-luvr

Just cruising threads looking for info on 5th, 6th port dynamics (specifically cutback) and came across a thread stating that european 5th,6th ports use butterfly valves and not rotating sleeves?

Why Mazda did this is a complete mystery. Published power figures were the same for both engines. Personally I think it's a better system but only because it was actuated by an ECU-controlled vacuum solenoid similar to the S5's.

There's some info and pics in here:

http://wombat.sevarg.net/RX7/RX-7_Tr...%20Systems.pdf (~3.5MB)