Been reading a few threads and noticed some of you are running the S&S Super Street. Just bought a 114 Fat Bob Wednesday and I already find myself planning mods and the engine build. My question about the pipe is different than most. Do any of you have a dyno chart you would share? I am not interested in peak numbers, mainly want to see the torque curve it produces. There are quite a few short stubby pipes out there and I do not like them because most cause a low rpm torque loss, I ride hard and enjoy torque when hammering it out of the curves. The S&S seems to be a mid length and I like the looks of it but would love to see a torque curve from a bike using this pipe. If its too soft down low I will have to go with the Fat Cat.

 

Wish I could help you out but I haven't had it on a dyno yet. Based on feel, it most definitely does well down low, as well as throughout the RPM range, but the dB reducer must be installed. Without it, the pipe is too wide open and loses the performance down low mostly but throughout the RPMs as well.

The sound was a bit too soft for me with the dB reducer installed in it's original form so I chopped it down in length. This made the pipe louder while maintaining the performance. Now it performs great and has the perfect tone to me.

I know this wasn't much help but hopefully gives an idea. Maybe someone will have a dyno chart with this pipe to post soon because I would be interested to see if it matches my seat of pants assessment and I think it probably will. I'm betting this pipe had a great torque curve with minimal dips.

It is most definitely a better all around performing pipe than the Bassani RR3 I had installed, again by the feel of the seat of my pants. One other thing to consider is clearance. I think the performance difference between the Fat Cat and the Superstreet would be minimal. With performance set aside, the Fat Cat is known to scrape based off of reports I got from another 2018 Fat Bob owner that is running the Fat Cat.

I have yet to scrape the Superstreet and have tried hard to be sure it won't scrape. Have only had my foot peg touch in corners again as was the case with the stock exhaust. Ground clearance was one of the biggest factors and deal breakers for me when deciding on which pipe to purchase. If you like carving it up hard like I do, the Fat Cat may limit and reduce your right-hand lean angle. Just something else to keep in mind. Good luck.

P.S. sorry for the novel here.

 

That db reducer you speak of could also be used to flow the exhaust (tune the torque curve). You can use a flow bench to set the flow on heads, throttle body, intake, exhaust... Depending on how the db reducer is made, a guy could do many things to tweak the exhaust: the length could be cut, hole diameter enlarged, extra holes drilled or tabs welded in. Some db reducers can be rotated to expand or reduce the hole size. The primary pipe length and merge of the two pipes also play a large role.
I hear ya on the fat cat. My old twin cam drug with the fat cat, the low cat and the rush wrath. The D&D pipes drug on the front primary pipe, the Wrath drug the very tip of the exit cone. The power was so good with the Wrath and I loved the sound, so I lived with it. The D&D fat cat made great power but scraped too hard, the low cat had a huge torque dip which also hurts peak numbers.
Looking at a post made by Fuel Moto in the Dyno section (post 1399), that fat cat seems to sit a lot higher than the twin cam model. I like the look of the S&S pipe though

P.S. I do not mind a novel, been know to write them myself lol

 

Since I'll get a tuner at the same time I buy an exhaust, I'll talk to Fuel Moto about my choices, thinking they can steer me in a good direction.
I'm not decided yet if the Super Street is best for me. Mostly the people I ride with are not into going quick so sound and looks are also important to me.
The other two exhausts on my list right now is the S&S Grand National and Rinehart 2-1 We'll see.
PS: Maybe less dyno runs on the newer pipes and M8 because of the good tuners and maps available.

 

Good point Mike, not a lot of Dyno results on Softail M8's
Just purchased a Cobra 2-1( not fitted yet) for my 19 Fatty, based on i like the look ,price point, its black

 

Just had the s&s grand national full system installed along with the hd 447 torque cam and powervision tuner with a custom tune from fuel moto. This system is available with or without cats. Got the one without on ebay for $744. VERY happy with the results. Pulls hard from idle, sounds awesome, plenty of ground clearance, and just seems to compliment the fatbob look. No dyno but Jamie from fuel moto got the tune spot on imo. I prefer leaving the db reducers in as too loud without for me. I have a short video on you tube that I cant seem to upload on here. Search s&s grand national full system. 52 second long

 

Looks great!
Can't find the video, can you just post a link?

 

I had the same experience with the Bassani RR3. I was scraping the front head pipe so I was not happy having to be really conservative cornering to the right. It's all good now!

I thought about deilling holes in the dB reducer but decided just to chop it. Seems to have worked well but I don't know for sure. I still have the chopped section of the dB reducer pipe so if I need to make adjustments when I do the stage 2 cam I can have my buddy weld it back and start experimenting with it. For now it's running like a beast so I'll leave it as is.

I liked the sound of the Fat Cat I heard in person but just didn't want to deal with the scraping so it was a deal breaker for me. It does sit a bit higher but it was confirmed by the guy who let me listen to the Fat Cat that it scrapes on his Fat Bob. Good performing and sounding pipe, just wasn't willing to give up the lean angle any longer.


I think you can't go wrong with either of those choices. Let us know what you finally decide on. And I think you're correct on the good maps available. My bike is running great with the canned map from FM and a few autotunes. May run a few more to try to fine tune it a bit more but I'm pretty happy with it so far.

I'll have a dyno chart sometime fairly soon but not until I swap the cam. Until then all I can say is this pipe feels great. It's nice and deep with a mello rumble at idle and while cruising and has a nice deep racy roar when getting on it.

 

I'm thinking the Rinehart's going to be louder than the S&S with Db reducer installed, but is a different look.

 

Just copy the link and paste it in your post. Most of the time the video will appear in the text. If not the link will be active and take us right to the video. Looks good! Looking at the head pipes, it seems they are very similar to the Superstreet but just don't go into the 2 into 1 collector.