On demand muffler bypass valve
03-12-2006, 02:56 PM
#1
On demand muffler bypass valve
Am toying w/ the idea of getting a couple of these to connect the two pipes going into the mufflers, sort of a muffler bypass on demand like the Ruf one?
http://www.atpturbo.com/Merchant2/me...egory_Code=BCS
They also have a simpler one: http://www.atpturbo.com/Merchant2/me...egory_Code=BCS
The question is if you want it to activate on WOT only or alternatively just w/ a switch, where would you hook the vacuum line to..
http://www.atpturbo.com/Merchant2/me...egory_Code=BCS
They also have a simpler one: http://www.atpturbo.com/Merchant2/me...egory_Code=BCS
The question is if you want it to activate on WOT only or alternatively just w/ a switch, where would you hook the vacuum line to..
03-12-2006, 05:23 PM
#3
Banned
Join Date: Nov 2003
Location: En La Boca Del Raton
Posts: 1,341
Likes: 0
Received 0 Likes
on
0 Posts
What I have done before is hook it to the vaccum line via a press activated switch, you can select whatever the pressure you whant the valve to open to, or you can hook it to a sw. in the throtle mechanism to activate a press sw. for the signal to the valve.,cheers,Sonny.
03-13-2006, 01:04 AM
#4
Three Wheelin'
Brad. I've been thinking of doing exactly this with th ATP setup. Looking at the stock exhaust, the best place to place each of these bypasses is just after the turbo and before the CAT. Right where the piping turns to join the CAT housing, you can place one there and straight out to join your existing exhaust tips. This would be a straight shot out from the turbo's which will yield maximum effect. Make sure the butterfly valve opens up and down, not side to side.
Jaime
Jaime
03-13-2006, 02:20 AM
#5
Banned
Rennlist Member
Rennlist Member
Join Date: Jul 2004
Location: California, Bay Area
Posts: 577
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by ttAmerica RoadsterAWD
Brad. I've been thinking of doing exactly this with th ATP setup. Looking at the stock exhaust, the best place to place each of these bypasses is just after the turbo and before the CAT. Right where the piping turns to join the CAT housing, you can place one there and straight out to join your existing exhaust tips. This would be a straight shot out from the turbo's which will yield maximum effect. Make sure the butterfly valve opens up and down, not side to side.
Jaime
Jaime
03-13-2006, 02:23 AM
#6
Rennlist Member
Originally Posted by sonny1
What I have done before is hook it to the vaccum line via a press activated switch, you can select whatever the pressure you whant the valve to open to, or you can hook it to a sw. in the throtle mechanism to activate a press sw. for the signal to the valve.,cheers,Sonny.
03-13-2006, 02:17 PM
#7
Three Wheelin'
K24.....you are right in your question. Guess it really does not matter. For some reason I was thinking It made a difference, but now I see it doesn't.
Jaime
Ok wait a minute......if the valve is placed so it opens up and down while the exhaust makes the turn, it will see the edge of the valve only......if the valve face opens Left to right, the flap will stick into the flow face-on as the exhaust rounds the 90 degree turn. I think it's valid, but I can be corrected.
anybody??
Jaime
Jaime
Ok wait a minute......if the valve is placed so it opens up and down while the exhaust makes the turn, it will see the edge of the valve only......if the valve face opens Left to right, the flap will stick into the flow face-on as the exhaust rounds the 90 degree turn. I think it's valid, but I can be corrected.
anybody??
Jaime
Trending Topics
03-13-2006, 07:45 PM
#8
Why do I feel so left out!
Rennlist Member
Rennlist Member
Ok - not sure how this is going to be taken.....but why???
If you have sport mufflers, arent you happy with the sound? Or is this a stock muffler modification?
I recently modified my stock mufflers.( I have By Pass pipes but these are too loud for our traffic rules down here) I was watching the thread on the 993 Forum where Leland Pate (sp?) did a bypass section between the inlet and the outlet of the muffler to increase sound.
This is a fixed section of pipe and retains EVERYTHING else that is stock (internals etc). So I took the plunge and took it to a buddy of mine that did the same. (LP's were on a N/A engined car - as the pipes take a different route - it was a little harder on our mufflers)
Now - the results - At first I was disappointed with the sound.... SO SO much quieter than the by pass pipes (not hard really) but definintly louder than stock. (sorry cant compare to RSR's - none down here) Much more 'meat" down low but the turbos didnt spool up as fast ( noticble with the by pass pipes) and as the rev range rose - the sound got better and better.
After a few miles - and getting used to it - it now sounds the way it should! When at full noise and high in the rev range - a great By Pass type RASP from the exhaust - but no where near as offensive as the BY pass pipes at full noise. Power doesnt seem to be as affected - BUTT dyno - but hard to tell when not on the track. (Will get around to dynoing the 2 later in the year when I get some time booked)
The bad bits - Obviously the flow path is interupted - unlike the By Pass pipes as the pipe is welded at 90 dergrees to the flow - but clearly as the back pressure of the mufflers slows exahust gas flow - then it will "overflow" into the by pass part of the pipe and will take the shorter route out the tips...
When i get home toniught - I will post some pics of the mod if anyone is interested.
Just begs the question - why have the switchable one when it is NOT offensive at low revs? Is that why you want them to be switchable?
Just my $0.02 worth,
Simon
If you have sport mufflers, arent you happy with the sound? Or is this a stock muffler modification?
I recently modified my stock mufflers.( I have By Pass pipes but these are too loud for our traffic rules down here) I was watching the thread on the 993 Forum where Leland Pate (sp?) did a bypass section between the inlet and the outlet of the muffler to increase sound.
This is a fixed section of pipe and retains EVERYTHING else that is stock (internals etc). So I took the plunge and took it to a buddy of mine that did the same. (LP's were on a N/A engined car - as the pipes take a different route - it was a little harder on our mufflers)
Now - the results - At first I was disappointed with the sound.... SO SO much quieter than the by pass pipes (not hard really) but definintly louder than stock. (sorry cant compare to RSR's - none down here) Much more 'meat" down low but the turbos didnt spool up as fast ( noticble with the by pass pipes) and as the rev range rose - the sound got better and better.
After a few miles - and getting used to it - it now sounds the way it should! When at full noise and high in the rev range - a great By Pass type RASP from the exhaust - but no where near as offensive as the BY pass pipes at full noise. Power doesnt seem to be as affected - BUTT dyno - but hard to tell when not on the track. (Will get around to dynoing the 2 later in the year when I get some time booked)
The bad bits - Obviously the flow path is interupted - unlike the By Pass pipes as the pipe is welded at 90 dergrees to the flow - but clearly as the back pressure of the mufflers slows exahust gas flow - then it will "overflow" into the by pass part of the pipe and will take the shorter route out the tips...
When i get home toniught - I will post some pics of the mod if anyone is interested.
Just begs the question - why have the switchable one when it is NOT offensive at low revs? Is that why you want them to be switchable?
Just my $0.02 worth,
Simon
03-13-2006, 09:43 PM
#9
Banned
Join Date: Nov 2003
Location: En La Boca Del Raton
Posts: 1,341
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by LUISJR993
Sonny, you did this to your 964? OT: Where in San Juan are you? I grew up in Garden Hills (Guaynabo).
03-13-2006, 10:29 PM
#10
Rennlist Member
Originally Posted by sonny1
Don't have a 964, I pick up that avatar from the list, use to have something similar,I did it to a customer TT, my ride is a 993tt, not stock, "GT2" everything! Live in Isla Verde, work in Arecibo, fun in La Parguera.,salud!
