SL55/63/65/R230 AMG: Will Removing Cats on SL65 Increase HP?
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06 SL65AMG, 13 Tesla Model S 60kwh, 02 Jaguar S-Type 3.0, 12 S550 4 Matic, 07 E320 Bluetec, 06 LX470
Will Removing Cats on SL65 Increase HP?
This Monday my car is finally getting a custom fabricated exhaust which different sections being V-banded incase I ever wanted to swap piping out
Its going to be 3 inch all the way around, no cats (will swap a cat in when its emission time lol), x pipe, and dual exhaust cutoffs right before the high flow muffler for that muffler delete sound when I feel like turning it on. (wanted to do one more cut off before the cat and x pipe but there isn't any room)
My question is will I see any HP gain by removing the cats? I've read some people saying there SL65s will not loose any HP but will not gain either, but the sound is much nicer. And I've heard others say 20-30 HP gain when you dyno it. Either way I'm gonna do the exhaust anyways so I dont have to worry about messing up my cats when I put race gas in and I prefer a louder sound then the OEM exhaut. But I'm curious if I will see any HP gain.
I figure every little helps when your tuning this beast to push out ridiculous amount of HP.
Its going to be 3 inch all the way around, no cats (will swap a cat in when its emission time lol), x pipe, and dual exhaust cutoffs right before the high flow muffler for that muffler delete sound when I feel like turning it on. (wanted to do one more cut off before the cat and x pipe but there isn't any room)
My question is will I see any HP gain by removing the cats? I've read some people saying there SL65s will not loose any HP but will not gain either, but the sound is much nicer. And I've heard others say 20-30 HP gain when you dyno it. Either way I'm gonna do the exhaust anyways so I dont have to worry about messing up my cats when I put race gas in and I prefer a louder sound then the OEM exhaut. But I'm curious if I will see any HP gain.
I figure every little helps when your tuning this beast to push out ridiculous amount of HP.
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From: Southern, CA.
V12-Biturbo
Adds hp/tq but also moves that power higher in rpm band.. The sound will amaze you, like no other car Ive ever heard, unlookers comment all the time "WTF that cars insane!"
Edit: Quickens throttle response too.. Should be 1st mod to any v12 tt, 3" catless down pipes/leave factory H pipe, X pipe doesnt add squat on these cars, it just quiets decell burble down, which is going backwards inmop. Run 3" back & hack off mufflers.. Perfect recipe trust me Ive done every mod possible to these cars..
Edit: Quickens throttle response too.. Should be 1st mod to any v12 tt, 3" catless down pipes/leave factory H pipe, X pipe doesnt add squat on these cars, it just quiets decell burble down, which is going backwards inmop. Run 3" back & hack off mufflers.. Perfect recipe trust me Ive done every mod possible to these cars..
Last edited by Thericker; Dec 11, 2013 at 03:00 AM.
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From: CT
CTS-V
Turbos don't like back pressure. You will likely gain some power, albeit, not a ton. I still have my cats, but no mufflers. LOVE the sound, but I wonder if no cats would be too loud? How much are Eurocharged DP's? Anyone else have some?
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06 SL65AMG, 13 Tesla Model S 60kwh, 02 Jaguar S-Type 3.0, 12 S550 4 Matic, 07 E320 Bluetec, 06 LX470
There making a one off set for mine, Kleemann has DP but they I can't find a price for it anywhere.
Speedriven has 2 sets of exhaust systems one that just a no cats and the other is something that passes emission (maybe ecu flash or O2 sensor bypass?) the first option was 1990 the second option was 2490.
Eurocharged is doing mine for 2700 for a 3 inch mandrel bent, but this is also including the dual electric exhaust cut offs which is another 350-400 and high flow mufflers which is another 100? so that's pretty good compared to Speedriven and they will re-dyno my car for free as well as make an extra hi flow cat pipes to v band when it's emission time. Paul said he can offer pretty much the same exhaust once he gets mine built and can copy it to resell for cheaper. I figure that way when it gets too loud ill block the cut off pipe and have it go through the muffler. I wish the SL65's had room to put the cutoffs right after the turbos or a little further down, but it doesn't seem like it, but since everything is gonna be V-banded I can try experimenting with that later.
Speedriven has 2 sets of exhaust systems one that just a no cats and the other is something that passes emission (maybe ecu flash or O2 sensor bypass?) the first option was 1990 the second option was 2490.
Eurocharged is doing mine for 2700 for a 3 inch mandrel bent, but this is also including the dual electric exhaust cut offs which is another 350-400 and high flow mufflers which is another 100? so that's pretty good compared to Speedriven and they will re-dyno my car for free as well as make an extra hi flow cat pipes to v band when it's emission time. Paul said he can offer pretty much the same exhaust once he gets mine built and can copy it to resell for cheaper. I figure that way when it gets too loud ill block the cut off pipe and have it go through the muffler. I wish the SL65's had room to put the cutoffs right after the turbos or a little further down, but it doesn't seem like it, but since everything is gonna be V-banded I can try experimenting with that later.
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From: Palatine, IL
Speedriven
There making a one off set for mine, Kleemann has DP but they I can't find a price for it anywhere.
Speedriven has 2 sets of exhaust systems one that just a no cats and the other is something that passes emission (maybe ecu flash or O2 sensor bypass?) the first option was 1990 the second option was 2490.
Eurocharged is doing mine for 2700 for a 3 inch mandrel bent, but this is also including the dual electric exhaust cut offs which is another 350-400 and high flow mufflers which is another 100? so that's pretty good compared to Speedriven and they will re-dyno my car for free as well as make an extra hi flow cat pipes to v band when it's emission time. Paul said he can offer pretty much the same exhaust once he gets mine built and can copy it to resell for cheaper. I figure that way when it gets too loud ill block the cut off pipe and have it go through the muffler. I wish the SL65's had room to put the cutoffs right after the turbos or a little further down, but it doesn't seem like it, but since everything is gonna be V-banded I can try experimenting with that later.
Speedriven has 2 sets of exhaust systems one that just a no cats and the other is something that passes emission (maybe ecu flash or O2 sensor bypass?) the first option was 1990 the second option was 2490.
Eurocharged is doing mine for 2700 for a 3 inch mandrel bent, but this is also including the dual electric exhaust cut offs which is another 350-400 and high flow mufflers which is another 100? so that's pretty good compared to Speedriven and they will re-dyno my car for free as well as make an extra hi flow cat pipes to v band when it's emission time. Paul said he can offer pretty much the same exhaust once he gets mine built and can copy it to resell for cheaper. I figure that way when it gets too loud ill block the cut off pipe and have it go through the muffler. I wish the SL65's had room to put the cutoffs right after the turbos or a little further down, but it doesn't seem like it, but since everything is gonna be V-banded I can try experimenting with that later.
Actually our downpipes are 1090 with no cats and 1290 with 200 cell cats. The 200 cell pass's smog and the cat less pass's odd
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06 SL65AMG, 13 Tesla Model S 60kwh, 02 Jaguar S-Type 3.0, 12 S550 4 Matic, 07 E320 Bluetec, 06 LX470
Update the website!!! lol and whats the deal with these new intake pics I've been seeing for the SL65? I've been curious about that
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From: Palatine, IL
Speedriven
Yes were sorry, the site is being updated currently. In regards to the intakes it involves a lot of modification to the car so we wont offer those unless it is a in house project car
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06 SL65AMG, 13 Tesla Model S 60kwh, 02 Jaguar S-Type 3.0, 12 S550 4 Matic, 07 E320 Bluetec, 06 LX470
Just ordered some K&N Air filters since I'm getting the car re-dynoed, might as well get the filters in now for that extra 5-10 HP some people claim, I wont know till I dyno it, but hey every little helps.
Do I need to wash they out or check for debris? I heard some people getting CEL when they don't clean them out right
Also if anyone is wondering I got my KNs from Partgeeks. They had them for 57.08 and 8.95 flat ground shipping so I figured its a great price for both filters
Do I need to wash they out or check for debris? I heard some people getting CEL when they don't clean them out right
Also if anyone is wondering I got my KNs from Partgeeks. They had them for 57.08 and 8.95 flat ground shipping so I figured its a great price for both filters
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From: CT
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Right, K&N filters only work if they are oiled...and kept clean and oiled. To me it's not worth the aggravation. IF we had MAF's, the oil would contaminate the MAF and wreak havoc...I will stick to stock paper filters...
