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10-18-2020, 09:42 PM | #1 |
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VRSF Downpipe SLIGHT vibration- maybe raise the idle RPM?
Hey guys. I just got the VRSF downpipe installed. Installation was done professionally by a friend/tech with 13 years experience at the dealership. He now builds race cars.
I LOVE the downpipes. Absolutely perfect fitment and great sound. Car effortlessly flies. 10/10, love them. Now— I noticed an ever so slight vibration at idle (not install OR fitment related). i took my gf for a drive and she couldn't notice it AT ALL. I noticed while driving, it's not there. With AC on at idle, also not there! Maybe i just never noticed this vibration with the stock downpipe? I'm thinking because the AC makes the car idle at 700 vs 600 rpm, this makes that vibration go away. Maybe I should adjust the idle RPM by 50-100rpm? should that make a difference?
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10-18-2020, 09:54 PM | #2 |
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Did you make sure to re-clip the o2 sensor wires at each spot? I remember there was a crap load of little clips on the edge of the heat shields that I had to push back on. Maybe one is loose or vibrating?
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10-18-2020, 10:16 PM | #3 | |
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This thing with my post is that it's not really a "vibration." It's not something anyone else would feel. I think maybe it's just the lack of the flex joint?
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10-18-2020, 10:32 PM | #4 |
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My ER sport cats are pretty big and don't have a flex joint. I had no vibration from them with my factory exhaust. Maybe it's the pulses going down the open pipes that you feel? My vibration started after I installed my AA Signature exhaust kit. Catted DPs with a 3.5in school-bus exhaust really makes some noise.
To check for rattles or vibrations I jacked the car and put a stack of 3 cut 2x8 wood blocks under the tires, then lowered onto the blocks. Start the car. Go lay next to the passenger side and use your sneaker to push on the (hot) pipes. If a vibration starts/stops you found a spot to check better. If no footwork changes the sounds then there's nothing to fix. Sometimes a few chips of a wine cork can be wedged under a vibrating heat shield to quiet things down. Best to check when cold, things rattle more.
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10-19-2020, 08:23 AM | #6 | |
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It's not really a "vibration" like i stated. I'm willing to bet money that no one would feel it other than me as i'm the owner and changed something on the car. It might just be because it is all a bit stiffer (no flex joint). I think imm just going to raise the idle RPM in BM3 by about 50-100rpm.
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10-19-2020, 08:24 AM | #7 | |
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I don't think it's anything actually "vibrating," but rather like you said... just stiffer with no flex joint. It's not really an issue.
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10-20-2020, 02:55 PM | #11 | |
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Is it because these don't have the transmission mount and flex joints?!? I'm not a fan after driving 2 more times.
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10-20-2020, 03:27 PM | #12 |
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Do the VRSF not have the little bracket on the long pipe that acts as a hanger, like the OEM (and my ER sport cats) have?
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10-20-2020, 03:31 PM | #13 | |
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That and the flex joints are the difference... Guess what? I just ordered the Active Autowerke downpipes... i just hateeeeee money.
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