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jran76 · 05-10-2011, 11:53 AM

Just a couple comments because I am too lazy to respond to all of it (and I agree with most of what you are saying)....

Turbulent air is more of an issue at the MAF sensors, or pre-MAF, and I will agree that in general turbulent air is a bad thing (it just has less of an affect once being sucked in under vacuum). The biggest issue (and one that some aftermarket intakes suffer from) is the affect of turbulent air has on readings by the MAF sensor. I do think Stillen's design helps keep turbulent air to a minimum pre-MAF, and one of the primary reasons it performs better than most other aftermarket intakes.

From all the testing I have seen (by 2-3 extremely reputable companies), there is nothing to indicate the stock boxes are in any way restrictive, or cannot provide enough air to the engine. I think the Stillen brings in slightly cooler and more air on the dyno, and that is the big advantage. At speed, I don't think the amount of air the factory boxes can flow is an issue. They are also bringing in a lot of the cooler air the Stillen is going to pull in once the car is in motion.

Also, one last comment on the throttle plates/bodies, according to Mike Kojima (who did a lot of research on the VQ37VHR early on):
"The unique VVEL system completely controls the intake valves opening and closing events.... The command authority of the VVEL system is great enough so controlling valve opening is the primary means of throttling the VQ37VHR’s output, instead of traditional throttle plates.The VQ37VHR does retain twin drive by wire throttles but they mostly stay wide open, the only time they close is on overrun to help provide engine braking and if the engines ECU detects low vacuum in the brake booster reservoir."

Reference (full article): Edit.... The link is blocked, I guess because it is from another site (god forbid should we share relevant information). If anyone really cares about it, I am sure you can search for Mike Kojima's site and find the article I quoted.

05-10-2011, 11:53 AM	#20 (permalink)
jran76 Base Member Join Date: Nov 2009 Location: Plano, TX Posts: 74 Drives: 09 G37S Sedan 6MT Rep Power: 15	Just a couple comments because I am too lazy to respond to all of it (and I agree with most of what you are saying).... Turbulent air is more of an issue at the MAF sensors, or pre-MAF, and I will agree that in general turbulent air is a bad thing (it just has less of an affect once being sucked in under vacuum). The biggest issue (and one that some aftermarket intakes suffer from) is the affect of turbulent air has on readings by the MAF sensor. I do think Stillen's design helps keep turbulent air to a minimum pre-MAF, and one of the primary reasons it performs better than most other aftermarket intakes. From all the testing I have seen (by 2-3 extremely reputable companies), there is nothing to indicate the stock boxes are in any way restrictive, or cannot provide enough air to the engine. I think the Stillen brings in slightly cooler and more air on the dyno, and that is the big advantage. At speed, I don't think the amount of air the factory boxes can flow is an issue. They are also bringing in a lot of the cooler air the Stillen is going to pull in once the car is in motion. Also, one last comment on the throttle plates/bodies, according to Mike Kojima (who did a lot of research on the VQ37VHR early on): "The unique VVEL system completely controls the intake valves opening and closing events.... The command authority of the VVEL system is great enough so controlling valve opening is the primary means of throttling the VQ37VHR’s output, instead of traditional throttle plates.The VQ37VHR does retain twin drive by wire throttles but they mostly stay wide open, the only time they close is on overrun to help provide engine braking and if the engines ECU detects low vacuum in the brake booster reservoir." Reference (full article): Edit.... The link is blocked, I guess because it is from another site (god forbid should we share relevant information). If anyone really cares about it, I am sure you can search for Mike Kojima's site and find the article I quoted. __________________ 2009 G37S Sedan-6MT: Advan / Volk / Tein / SPC / Invidia / Cobb / K&N Last edited by jran76; 05-10-2011 at 11:57 AM.