post cat removal question
Thread Starter
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Road Warrior
Joined: Oct 2009
Posts: 1,317
Likes: 16
From: Texas
post cat removal question
Once cat is removed from a 2010 SG, can you run with stock pipe setup and no other mods as long as you don't upgrade the AC?
I have a stock 2010, just gutted the cat, and threw on a thunderheader slip on. I have a PCV and SE AC coming later this week but would like to know if its ok to ride it as is until those items come in. I did a test ride around the neighborhood and it sounded GREAT! however there was some popping when i let off the throttle so wondering if its running too lean and if i should just wait.
Also, MGR at local dealership says slip on thunderheader with de catted stock pipe will lose HP, and that I need to add a pipe inside header to build back pressure. Not sure he knows what hes talking about as he also said I would lose HP on stage 1 upgrade, when the service dept says Ill get increased gains across the board.
Thanks for any feedback on this.
I have a stock 2010, just gutted the cat, and threw on a thunderheader slip on. I have a PCV and SE AC coming later this week but would like to know if its ok to ride it as is until those items come in. I did a test ride around the neighborhood and it sounded GREAT! however there was some popping when i let off the throttle so wondering if its running too lean and if i should just wait.
Also, MGR at local dealership says slip on thunderheader with de catted stock pipe will lose HP, and that I need to add a pipe inside header to build back pressure. Not sure he knows what hes talking about as he also said I would lose HP on stage 1 upgrade, when the service dept says Ill get increased gains across the board.
Thanks for any feedback on this.
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
Once cat is removed from a 2010 SG, can you run with stock pipe setup and no other mods as long as you don't upgrade the AC?
I have a stock 2010, just gutted the cat, and threw on a thunderheader slip on. I have a PCV and SE AC coming later this week but would like to know if its ok to ride it as is until those items come in. I did a test ride around the neighborhood and it sounded GREAT! however there was some popping when i let off the throttle so wondering if its running too lean and if i should just wait.
Also, MGR at local dealership says slip on thunderheader with de catted stock pipe will lose HP, and that I need to add a pipe inside header to build back pressure. Not sure he knows what hes talking about as he also said I would lose HP on stage 1 upgrade, when the service dept says Ill get increased gains across the board.
Thanks for any feedback on this.
I have a stock 2010, just gutted the cat, and threw on a thunderheader slip on. I have a PCV and SE AC coming later this week but would like to know if its ok to ride it as is until those items come in. I did a test ride around the neighborhood and it sounded GREAT! however there was some popping when i let off the throttle so wondering if its running too lean and if i should just wait.
Also, MGR at local dealership says slip on thunderheader with de catted stock pipe will lose HP, and that I need to add a pipe inside header to build back pressure. Not sure he knows what hes talking about as he also said I would lose HP on stage 1 upgrade, when the service dept says Ill get increased gains across the board.
Thanks for any feedback on this.
Thread Starter
|
Road Warrior
Joined: Oct 2009
Posts: 1,317
Likes: 16
From: Texas
Hay TUCCI, bigdogx, thanks for the info. Ive heard from some folks that it should be fine as long as ac stays stock, but that popping on decel is a sign its running too lean or something is wrong. Are you using stock muffler? I am using a thunderheader slipon and wonder if that has any change to the equation.
Last edited by SmittyFXDL; Oct 17, 2011 at 10:31 AM.
Regardless of manufacturer, it is a wise idea to add a tuner when modifying or replacing headpipes. The cats create a lot of back pressure and once removed, depending on the slipons, you could create a situation where there is not enough back pressure for the narrow band O2 sensors to operate properly. As the old saying goes tuning is not always required but it's always recommended. Usually if you do intake and exhaust upgrades, you will not see the full power increase the upgrades are capable of until you add a properly tuned fuel management system.
Keeping the AC stock will increase your chance of not requiring tuning, but like I said before it's always recommended.
Popping (loud backfire, not just a flutter) is a sign you should have things checked out. This usually means you have an exhaust leak or it's running lean.
-Ryan
Keeping the AC stock will increase your chance of not requiring tuning, but like I said before it's always recommended.
Popping (loud backfire, not just a flutter) is a sign you should have things checked out. This usually means you have an exhaust leak or it's running lean.
-Ryan
Thread Starter
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Road Warrior
Joined: Oct 2009
Posts: 1,317
Likes: 16
From: Texas
Hay Ryan, thanks for the info. I plan on going back over the work completed so far after work today as it was a late night last night when I finished up the pipe swap. Probably need to double check the exhaust head bolts and muffler clamp to make sure I wasn't too easy on it. When it comes to exhaust head bolts im very gun shy as Ive snapped them off in past on older bikes and that is one road I do not want to go down again.
Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
Likes: 224
From: Glendale AZ
Hay TUCCI, bigdogx, thanks for the info. Ive heard from some folks that it should be fine as long as ac stays stock, but that popping on decel is a sign its running too lean or something is wrong. Are you using stock muffler? I am using a thunderheader slipon and wonder if that has any change to the equation.
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Thread Starter
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Road Warrior
Joined: Oct 2009
Posts: 1,317
Likes: 16
From: Texas
Ok, got my pcv and ac yesterday. Install was pretty straightforward and easy. Installed pcv to proper plugs and tucked in front of battery. Disconnected o2 sensors on rt side panel. Then removed stock ac and installed se ac. Started up and sounded good enough. Took her for a ride today and man, nasty backfirin all the way home. It's in the 60's here which is unusually cool. I thought fed sure plugs would be white or very lean and they are tannish on top and sooty on threads. I'll post pics in just a few.
Any ideas on why she's back firing on decel so bad?
Any ideas on why she's back firing on decel so bad?
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Extreme HDF Member
Joined: Jun 2011
Posts: 10,216
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From: Glendale AZ
Well if we were dealing with carburetors I'd say to increase the PMS (Primary mixture screw) 1/4 turn out. But I'm not sure how you do it on a FI. If I could paste a pic of my stock plugs I could show you how they look identical. I only hear popping once in a great while. Not enough for me to agree that stock bikes are running too lean.