[T-Bone Malone]

I have been thinking about gutting my cat. The dealer says they’ve done a few but says there is a ton of horsepower loss. He also said the bikes they gutted cats on sounded poor. How much truth is there to this?

 

[Dr.Shifty]

The 'ton of horsepower loss' is a new one to me. Most people don't notice any difference in power.

The sound difference depends on what mods you have. Stock pipes with gutted cat sound a bit louder but with a nice rumble when I've listened to a mate's bike.

I have stage 1 pipes and 558 cams. The gutted cat sounded very loud (way over legal limit) and with an attack dog bark that was highly irritating to me, although riding mates sitting behind me said it was OK to them. The guy who did the cam swap said the extra overlap of the cams was a large part of the different note.

I swapped the gutted cat for a stock header with another mate who wanted to gut his own. I'm happy with the sound of the stock header and the mate is happy with the snarl of the gutted one.

 

[Gort]

You will lose some midrange torque, not HP. Sounds like they want to sell you an exhaust.

 

[Goindian]

I have been thinking about gutting my cat. The dealer says they’ve done a few but says there is a ton of horsepower loss. He also said the bikes they gutted cats on sounded poor. How much truth is there to this?

No truth to that? Cat removed on the last 3 Indian Baggers here for me; stage one air, stage two Indian cams, Rush true duals and Dyno Jet tune; running very close to 116 BBK for HP/Torque someone misleading you here.

 

[GreatWhite]

I guess someone would have to dyno the same Indian before and after. Share the result

 

[NDN]

I took the Cat out, replaced with the Libertyville X-Pipe, No HP loss and gained a better rumble from the pipes. Best thing was the wife said the right side was not as hot as it was before. Worth it to me. Reprogrammed the ECM with the fuel-Motor PCVX and I wont go back

 

[RoadmasterD]

I guess someone would have to dyno the same Indian before and after. Share the result

This and most other options have been done and are on Fuel Motos website

Dyno Charts - Fuel Moto University

Below you will find an assortment of sample dyno charts for various Harley combinations, this is a work in progress. We will be adding more & more Harley charts as well as Metric & Euro charts as we go from the 2000+ bikes we have tuned over the past 2 decades. Note the data in [...]

university.fuelmotousa.com

 

[GreatWhite]

This and most other options have been done and are on Fuel Motos website

Sweet. I will check it out. Thanks.

 

[Darthbagger]

Yeah, my buddy and I did the cat delete thingy. Got more grunt outta the pipes but now we ordered full headers since the crossover pipe is kinked so bad that you loose flow any ways and the new true duals are made so flowier and nice. I would just get headers and call it a day. Then get some cams. Then get air filter. Then get a power commander. Then get autotune. Then get 116 BBK and then your done. Maybe?

 

[Shuje Sunge]

I have been thinking about gutting my cat. The dealer says they’ve done a few but says there is a ton of horsepower loss. He also said the bikes they gutted cats on sounded poor. How much truth is there to this?

Little to none. I have an air cooled engine, ride in Texas and Oklahoma. Gutted the cat because of the heat, actually started melting the plastic cover right above the cat. Didn't go with any of the expensive upgrades, just gutted the cat. Already had Stage 1 pipes when purchased, added the Big Sucker air cleaner and got rid of the bed pan. There is no discernable gain or loss of HP however I noticed quicker throttle response, picks up RPM quicker. There is a slight more bark from the pipes. There is NO difference in torque and I lost a lot, I mean a LOT of heat. It's a 2014 Chief.

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[captain-kate]

I had my rear header pipe on my 2015 Chieftain de-catted by American Custom, and also used their "Bomber" mufflers (stock muffler with the inserts knocked out). Haven't noticed any decrease in HP. The exhaust sound better to me, but a tiny bit tinny at idle, but not in an obnoxious way. Next week I will be putting a new Voodoo air cleaner on along with a new PVCX tune from Craig.

 

[Indian-Corey]

I also had the cat gutted from the stock header and a diverter plate installed. There is a crap load of info on this forum under the 111 Performance tab here and it addresses this question as well as a list of aftermarket headpipes which ones are awesome and etc. I have an 18 with the stage 2 cams a tune from Craig B, a Lloydz air intake and RCX slip ons. My bike runs really good and there was a bit of change with the slip ons as I have noticed the tach climbs higher faster than it used to and engine is nice and quiet. One thing you may notice is a cold start ping when you start the bike. It goes away after it warms up. My cold start ping went away when I changed out slip on mufflers. If you go to fuel moto and look at their dyno sheets I think there is a stock dyno then one with a decatted head pipe but double but I could be wrong.

 

[JudsonTuc17Chieftian]

I have been thinking about gutting my cat. The dealer says they’ve done a few but says there is a ton of horsepower loss. He also said the bikes they gutted cats on sounded poor. How much truth is there to this?

I have have the stage 1 with reinhardts and a gutted cat. I haven't noticed and real loss of power at all, and the sound is just a little louder and a little more throaty.

 

[RonW64]

I recently gutted the cat on my '19 Chieftain Limited. Additionally, running stage 1 slip-ons, and a high flow air intake. I notice a little power loss in the lower range, but no change in the mid and upper ranges. If you do it, I highly recommend getting a tuner, and re-flash the ECU. I used Fuel Moto, and can honestly say they are great to work with. It took a few flashes before I got one I was satisfied with, and Craig at FM was very responsive and willing to help. I've read where some people complain about a "tinny" sound from the exhaust after gutting the cat. I haven't noticed that, but I do have more popping on decel. Gutting the cat is also supposed to help reduce heat from the exhaust. I haven't noticed a huge difference there.