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I do have some concerns about running with the flaps closed and the engine thinking they are wide open. I either have this right or wrong but it might make the engine run richer and if that's the case it won't be a major issue.
@CSL yes closed in all modes. We'll call it the Laguna Seca Mode or LSM.
Mine arrived today. Nice of them to include the stickers. I won't get a chance to try them out for a week or two. Nick give us an update if you install yours. If they work as advertised in LSM I'll be off to LS on Oct 28th.
Does the stock valve system only open/close the two inner pipes (the outer pipes are permanently open)? If the defeat plugs only defeat the inner pipes, the outer pipes should allow enough exhaust gases to come out without massively increasing back pressure.
I'm pretty sure the valve diverts exhaust from the outer pipes to the inner pipes. There is rarely any exhaust residue on the outer pipes as I usually run it in sport mode. So in this instance the valve will stay closed and exhaust will flow through the outer pipes only.
I finally tested my GrimmSpeed modules and they worked as advertised. Car is quiet under full acceleration and I'm confident it will pass 90db at Laguna Seca. LSM works well and allows you to use Track driving mode.
What took me so long to test them was as I was trying to install the modules I was having a tough time getting the connector to separate. What I didn't realize was not only do you have to slide the bar back you need to depress a part in order for them to separate. Regardless I thought it was a PITA reaching up on top of the muffler. While I was under the car I noticed there is a pigtail with heat shielding on it. The other end of the connector is very easy access and should make the job much easier. I sourced the pigtails from my local dealer and it worked beautifully. They were $42 for the both of them. Maybe a bit expensive for some added convenience but I think it's going to work well.
Note there are two different part numbers for passenger and drivers side. You could order two of either and it would work just as effectively. But you might as well order one of each in case the existing ones fail then you have a backup. The difference is one is about 2' longer than the other. Otherwise they are identical. The orange tag is for the drivers side and the green is for the passenger side.
The part numbers are:
FR3Z 14A411 H Drivers Side
FR3Z 14A411 J Passenger Side