msgs350

iTrader: (2)

I just ordered these, and should arrive this week (Sold and shipped from Amazon Prime) so hopefully I can install this weekend and report back on sound/drone since my car has headers, cat back Borla, AFE filter/JoeZ and high flow cats. BLKLBL- for sharing this info and did you ever try to contact Borla about their Venturis to reduce drone before trying this option?

BLKLBL

No I didn't contact Borla; I more or less stumbled upon these on Amazon while searching for 2" electric cut-outs that I could weld on to one of the Borla Outlets. Then I remembered from back in the day, we used to use bolt in silencers in the big 3" fart-cannons on our Hondas.. So I measured the outlets of the Borla, and found something that will fit in there.

Diesel350

Someone should try this on the Joe Z

FilwithanF

iTrader: (1)

This is great info guys, thanks for sharing! Eagerly awaiting the results from msgs350's car with the headers!

mikersoft

iTrader: (1)

Thanks for the additional info.. I didn't realize you were in Canada. I just ordered a pair to try out. At less than $17 delivered, I figure it's worth a try.

-Mike

MileHIFcar

I did and they sent the Venturis out to me a few days ago. Just need to set up a time to install them and I will report back with my results.

clarionguy

Has anyone tried to temporary "PLUG" the bottom outlet to see if the resonance sound completely changes to a different RPM?

MileHIFcar

I'm guessing there will no power loss with these and just enough back pressure being created in the chamber of the Borla mufflers to create some destructive interference to cancel out some droning frequencies?? The other opening in the mufflers will be pushing out the majority of the exhaust flow and changing the tone/frequency coming out resulting in a more subdued less booming exit/sound????

msgs350

iTrader: (2)

Good to know that you will be trying the Venturis out, especially since you have FBO. I have the Venturis in hand also but my pipes are welded where Borla recommends installing the pair before the resonator. I was going to install just 2 but decided to hold off.

Yes, I tried this last week. We just stuffed some rags on the bottom tips on both mufflers, for a moment and found that it suppressed the sound on start-up and revving a little bit.

msgs350

iTrader: (2)

I just received mine and put these in. Based on a quick assessment using a decibel meter iphone app (and by no means should my review be official in any way) the sound went from 99db to 94db with the silencers installed. For the price, these aren't bad and are worth it to me so far, and keep in mind, I have headers, and hi-flow cats installed. I can update this thread with additional info once i drive the car more but that may be a while as I only drive the car about 50 miles a week.

MileHIFcar

Awesome thanks for the update!

gbgary

cool. a shot of high-temp black paint wouldn't hurt.

BLKLBL

I checked mine today and with the DB iPhone app, my cold start went from 82db to 72db. Good to hear you have had a reduction also.
-- these are adjustable, if you want to quiet yours down down more, maybe re adjust the end piece so that it blocks off more of the holes, and see if that helps

msgs350

iTrader: (2)

My cold start, when car has been off for more than a few hours is around 105db. I adjusted it "1 notch" towards the exhaust exit and it didn't make a difference. At this time, I'm going to be happy with the 6db of sound reduction. Where is your's adjusted to (rear or front of car)? Thanks again for posting this and please post the info for cutouts when you can.

GSteg

iTrader: (15)

It's possible you might not notice a difference at partial throttle (ie. cruising around town). There are dyno sheets floating around the internet (for other cars) that shows power loss at the top-end. The more you stack together, the more restriction. Every car is different so I can't really say how much it'll affect the IS-F.

Want to reduce drone without power loss? Helmholtz resonator. Looks simple to the eye, but designing it is a different story.