Hello all,

I have a S&S Grand National 2-2 exhaust on my 2002 FXD, 95" TC engine. Has anyone done any dyno tuning using this exhaust? I am interested in finding out how it compares to other exhaust like for instance a Bassani 2-1 from a performance point of view.

For those not familiar with this exhaust it has 1-3/4" headers connected by a hidden crossover making it a 2-1-2 system if that makes sense. I really like the look of the dual mufflers and the sound is to my liking too, not overly loud but with a nice bite, sounds almost like an oversized super motard rather than a Harley

 

No offense, but for those charts to be relevant , the engine mods would have to be similar to yours.

 

[QUOTE=eighteight;21470386]I agree, and maybe a better question would have been "is the S&S Grand National 2-2 a good performance exhaust..?"

But as long as there is info about the engine configuration a dyno chart does provide at least some objective data, even if its not directly applicable to another engine setup.

Winter is long and cold here in Scandinavia so there is lots of time to ponder possible upgrades, and I'm simply trying to find out if I should continue with these pipes or if there are significant performance gains to be had by changing them to something different.

 

There are better 212s. Aren't they 50 state compliant and have a cat? That megaphone muffler is something i avoid like the plague. The stock decatted head pipes with a good pair of slip ons like the Khromeworks HP+ work quite well on M8s.

 

Its a 2002 dyna.......not an M8. Edit, and he lives in Sweden.....

 

Sorry, but I have no personal experience with these. But it looks like it has S&S heads on it, so there may be other engine mofdifications too. Some of those could affect the sound and performance of your bike when compared to others. Nice bike.

Paul

 

They don't have any cat, they are made for 2006 up Dynas but I was able to make them work on my 2002.

I think this exhaust would be very similar to stock headers with slip ons, same size headers, crossover pipe, mufflers are basically slip ons but cone shaped

 

Yes its a 95", 10.6:1 comp with Andrews 55 cams and HSR 42 carb. Last year I ran the same pipes with the stock 88" and S&S 509 cams, It does sound a bit more snappy with the current setup

 

Also, these pipes come with removable dB inserts to lower sound, I tried to run without them but did not like the sound, a loud annoying drone, and it also lost a lot of low end power, most likely due to reversion, my cams have 42 deg overlap.

I ended up cutting away half of the dB reducers, the butt dyno says I gained a bit compared to the full length, and the sound remained nice.

 

I found a dyno chart on S&S website, for a stock 103" TC:

(with the disclaimer that one should not draw too much conclusions from this, stock cams actually have no overlap so they are not sensitive to reversion at all, so even if the curve looks nice here there could still be a big dip in the mid range on an engine with large overlap cams like mine)



Seems quite equal to stock headers with slip ons on same engine: