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robertway · 02-10-2011, 05:09 PM

Installed my NOWEEDS Exhaust Diverters last week after having installed a cam the week before. I am running Kooks 1 7/8" headers with their Hi-Flow Cats and they hook up to the stock mid-pipes and garbage cans, I mean mufflers

. Last week when I got the car tuned we forgot to do a back-to-back with the diverters closed and then open so I had to wait until the shop could get me back in this week to do the pulls.

Steve at NOWEEDS.net was great to work with, he went out of his way to get my diverters in the next production batch so I didn't have to wait too long to finish my car after having done the cam and waiting on the diverters before going for a tune. When I received the diverters they were very well packaged and came complete with everything necessary to install including detailed instructions which are also available on their web site.

The install went very smooth and only took a couple of hours taking my time. I am not going to go into a DIY with pictures as member "CanadianCamaro" already did a very thorough DIY some time ago which I used along with the instructions from Steve at NOWEEDS.

I did run into one issue after install in that after a day's worth of driving and heat cycles into the diverters, the passenger-side unit would no longer close all the way and it's butterfly valve was falling short of full close by about 1/16" which doesn't seem like much but it something you can hear. I immediately reached out to Steve and within a short time had a response back that mentioned there is a possibility after the first few long heat cycles that the actuator may have to be adjusted slightly but this has only happened on rare occasions and he clearly outlined the procedure for adjusting the throw on the actuator which only took about 10 minutes from wheels up to wheels down in the garage. After the adjustment everything has been fine.

As for the pulls on the dyno, I got back into East Coast Supercharging who got me squeezed back in for a handful of pulls despite their hectic workload (and me pestering them for most of the week) to get the closed/open comparison and try to help put to rest whether they help at all. Getting in first thing in the morning, Matt at ECS had to get a few pulls in on their DynaPak dyno to get it warmed up a bit and there was already good temp in the car from the drive to the shop. After the warm-up pulls he did back to back pulls, first pull with the diverters closed, let the car settle back into idle for 15 seconds, open the diverters, and then pull again. The car gained 9RWTQ and 10RWHP with the diverters open and that was on the second pull of an immediate back to back. The gain really showed itself above 5000 rpm and all the way until the end of the pull. If we wanted to play dyno games we could have let the car cool off for 5-10 minutes and maybe seen a 15-20RWHP increase based on speculation but I think the back to back says a lot as numbers tend to drop off a bit on immediate back to back pulls, not increase so it is obvious the stock cans are choking the LS3 just a bit. Overall the car pulled a little less than it did the week before when it was tuned for the cam but "different day, different numbers" as the story goes, still kicking myself for not getting the open diverter pull done the same day the car was tuned to get some nice before/after cam and closed/open diverter graphs.

Here is a video with footage of idle, rev, in-cabin cruise, in-cabin acceleration, roadside fly-by, and dyno pulls all with the diverter closed/open comparisons. Video just does not do the sound justice. When the diverters were open on the dyno it was shaking the garage and you could feel the sound waves pounding you in the chest, and I was standing outside the door of the dyno room with the camera. TURN THOSE SPEAKERS UP!!!

For any haters out there that think the pulls weren't actually back-to-back with VERY little time between here is the unedited video as I had to split the above to get the different titles at the bottom of the screen. Back-to-back pulls, 15 seconds between, +9RWTQ and +10RWHP with dyno sheet.

The diverters really give me the best of both worlds in that I save my marriage by keeping the relatively quiet setup with the stock mufflers but also have the ability to scare children and rattle dentures when I want to. Looking forward to getting video of this thing hauling down the front straight at Pocono Raceway this coming summer

. Does it really matter that I gained 10RWHP, probably not as I would be hard pressed to feel it but I am just wondering how much more the car may pick up closed-to-open when the ECS Paxton Centri blower is on it as it is obvious the stock mid-pipes and cans are a bit restrictive.

Once again I have to thank Steve at NOWEEDS for his help both before and after the sale and as always Doug, Chris, Mike, and Matt at East Coast Supercharging for accommodating me and fitting in my "do over" pulls amidst their workload.

02-10-2011, 05:09 PM	#1
robertway Drives: 2012 Challenger SRT8 Auto Join Date: Sep 2009 Location: Central New Jersey Posts: 839	NOWEEDS Exhaust Diverters on LS3 with LTs (idle/rev/drive-by/dyno video) Installed my NOWEEDS Exhaust Diverters last week after having installed a cam the week before. I am running Kooks 1 7/8" headers with their Hi-Flow Cats and they hook up to the stock mid-pipes and garbage cans, I mean mufflers . Last week when I got the car tuned we forgot to do a back-to-back with the diverters closed and then open so I had to wait until the shop could get me back in this week to do the pulls. Steve at NOWEEDS.net was great to work with, he went out of his way to get my diverters in the next production batch so I didn't have to wait too long to finish my car after having done the cam and waiting on the diverters before going for a tune. When I received the diverters they were very well packaged and came complete with everything necessary to install including detailed instructions which are also available on their web site. The install went very smooth and only took a couple of hours taking my time. I am not going to go into a DIY with pictures as member "CanadianCamaro" already did a very thorough DIY some time ago which I used along with the instructions from Steve at NOWEEDS. I did run into one issue after install in that after a day's worth of driving and heat cycles into the diverters, the passenger-side unit would no longer close all the way and it's butterfly valve was falling short of full close by about 1/16" which doesn't seem like much but it something you can hear. I immediately reached out to Steve and within a short time had a response back that mentioned there is a possibility after the first few long heat cycles that the actuator may have to be adjusted slightly but this has only happened on rare occasions and he clearly outlined the procedure for adjusting the throw on the actuator which only took about 10 minutes from wheels up to wheels down in the garage. After the adjustment everything has been fine. As for the pulls on the dyno, I got back into East Coast Supercharging who got me squeezed back in for a handful of pulls despite their hectic workload (and me pestering them for most of the week) to get the closed/open comparison and try to help put to rest whether they help at all. Getting in first thing in the morning, Matt at ECS had to get a few pulls in on their DynaPak dyno to get it warmed up a bit and there was already good temp in the car from the drive to the shop. After the warm-up pulls he did back to back pulls, first pull with the diverters closed, let the car settle back into idle for 15 seconds, open the diverters, and then pull again. The car gained 9RWTQ and 10RWHP with the diverters open and that was on the second pull of an immediate back to back. The gain really showed itself above 5000 rpm and all the way until the end of the pull. If we wanted to play dyno games we could have let the car cool off for 5-10 minutes and maybe seen a 15-20RWHP increase based on speculation but I think the back to back says a lot as numbers tend to drop off a bit on immediate back to back pulls, not increase so it is obvious the stock cans are choking the LS3 just a bit. Overall the car pulled a little less than it did the week before when it was tuned for the cam but "different day, different numbers" as the story goes, still kicking myself for not getting the open diverter pull done the same day the car was tuned to get some nice before/after cam and closed/open diverter graphs. Here is a video with footage of idle, rev, in-cabin cruise, in-cabin acceleration, roadside fly-by, and dyno pulls all with the diverter closed/open comparisons. Video just does not do the sound justice. When the diverters were open on the dyno it was shaking the garage and you could feel the sound waves pounding you in the chest, and I was standing outside the door of the dyno room with the camera. TURN THOSE SPEAKERS UP!!! For any haters out there that think the pulls weren't actually back-to-back with VERY little time between here is the unedited video as I had to split the above to get the different titles at the bottom of the screen. Back-to-back pulls, 15 seconds between, +9RWTQ and +10RWHP with dyno sheet. The diverters really give me the best of both worlds in that I save my marriage by keeping the relatively quiet setup with the stock mufflers but also have the ability to scare children and rattle dentures when I want to. Looking forward to getting video of this thing hauling down the front straight at Pocono Raceway this coming summer . Does it really matter that I gained 10RWHP, probably not as I would be hard pressed to feel it but I am just wondering how much more the car may pick up closed-to-open when the ECS Paxton Centri blower is on it as it is obvious the stock mid-pipes and cans are a bit restrictive. Once again I have to thank Steve at NOWEEDS for his help both before and after the sale and as always Doug, Chris, Mike, and Matt at East Coast Supercharging for accommodating me and fitting in my "do over" pulls amidst their workload. __________________ "When the people find they can vote themselves money, that will herald the end of the republic." - Benjamin Franklin LS3 Camshaft Swap Do-It-Yourself Instructions - 2010 LS3 gone but not forgotten!!!