Rotary Car Club - View Single Post - Possible 4-Port N/A Start?

NoDOHC · 06-15-2010, 08:08 PM

Hey Buggy, I am curious what you get on the dyno with your setup. That will be interesting to contrast the power band of that engine to the one that I posted earlier from mine. You probably have a naturally better intake, but I am mostly interrested in low end, torque curve, etc. Also, what do you get for fuel economy?

To the original poster: Go 4-port FTW! I was worried about losing low-end going from a 6-port to a 4 port, but the 4-port stomps the 6-port above 1800 rpm. Meaning that you get better grunt, even on the interstate in high gear. Idle is good and mileage doesn't suffer much (35mpg 6-port -> 30 mpg 4-port with NA 5-speed, 25 mpg 4-port with turbo 5-speed).

The 4-port is easy to work on (all kinds of space where the turbo is supposed to go), runs cooler (could be from the lower compression ratio) and is much simpler to tune.

The only thing I would do differently if I ever get a chance would be to use NA rotors instead of turbo ones. I don't know if the small weight savings and additional 3 point on the compression ratio makes it worth the expense for RX8 rotors or e-shaft.

06-15-2010, 08:08 PM	#11
NoDOHC The quest for more torque Join Date: Sep 2008 Location: Sheboygan, Wisconsin Posts: 855 Rep Power: 17	Hey Buggy, I am curious what you get on the dyno with your setup. That will be interesting to contrast the power band of that engine to the one that I posted earlier from mine. You probably have a naturally better intake, but I am mostly interrested in low end, torque curve, etc. Also, what do you get for fuel economy? To the original poster: Go 4-port FTW! I was worried about losing low-end going from a 6-port to a 4 port, but the 4-port stomps the 6-port above 1800 rpm. Meaning that you get better grunt, even on the interstate in high gear. Idle is good and mileage doesn't suffer much (35mpg 6-port -> 30 mpg 4-port with NA 5-speed, 25 mpg 4-port with turbo 5-speed). The 4-port is easy to work on (all kinds of space where the turbo is supposed to go), runs cooler (could be from the lower compression ratio) and is much simpler to tune. The only thing I would do differently if I ever get a chance would be to use NA rotors instead of turbo ones. I don't know if the small weight savings and additional 3 point on the compression ratio makes it worth the expense for RX8 rotors or e-shaft. __________________ 1986 GXL ('87 4-port NA - Haltech E8, LS2 Coils. Defined Autoworks Headers, Dual 2.5" Exhaust (Dual Superflow, dBX mufflers) 1991 Coupe (KYB AGX Shocks, Eibach lowering springs, RB exhaust, Stock and Automatic)