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Silber · 09-29-2021, 06:19 PM

I hate to open the valve discussion again, but found new information.

HP Calculator Using Intake Valve Size

This calculates maximum theoretical horsepower of a well optimized engine given valve size.

According to their calculator, two 37.1mm intake valves, which is what the m96.21 3.2 has, on a 6 cyl is capable of flowing up to 430hp. That is a ceiling I can happily live with, not really even sure what to expect peak HP wise, but we will find out when it hits the dyno eventually.

I think the MAF and Throttle body are the biggest bottlenecks on the intake side, so will address those. After that the Boxster intake is the next weak link, but the 996 intake has some compromises so I’ll build with the Boxster S part, and retune later with a 996 intake if I’m not happy with the results on the Boxster part. Exhaust I’m as optimized as I’m going to get with equal length headers, high flow cats, and a free flowing muffler.

Regards,

Silber

09-29-2021, 06:19 PM	#57
Silber Registered User Join Date: Aug 2016 Posts: 169	I hate to open the valve discussion again, but found new information. HP Calculator Using Intake Valve Size This calculates maximum theoretical horsepower of a well optimized engine given valve size. According to their calculator, two 37.1mm intake valves, which is what the m96.21 3.2 has, on a 6 cyl is capable of flowing up to 430hp. That is a ceiling I can happily live with, not really even sure what to expect peak HP wise, but we will find out when it hits the dyno eventually. I think the MAF and Throttle body are the biggest bottlenecks on the intake side, so will address those. After that the Boxster intake is the next weak link, but the 996 intake has some compromises so I’ll build with the Boxster S part, and retune later with a 996 intake if I’m not happy with the results on the Boxster part. Exhaust I’m as optimized as I’m going to get with equal length headers, high flow cats, and a free flowing muffler. Regards, Silber __________________ 2002 Boxster S - Silver/Boxster Red Coilovers - LSD - CAI - High Flow exh. - F&R Adjustable Sways LN 3.2 to 3.8 - parts acquired, pending assembly and tuning Last edited by Silber; 09-29-2021 at 06:21 PM.