Hey guys, wanting to get some wrench turners ideas and thoughts about a recent dyno run. I have a 06 Mastiff. I of course have the 117 Ci, originally it was the EPA regulated motor. After talking to S&S and having a shop do the work it now is a non EPA regulated motor. S&S drop shipped everything that I needed to get the most out of the engine. The only known upgrades is a .600 S&S Cam, a Kerker 2 into 1 super megaphone without baffle, the BD Spike air cleaner. I'm sure its the factory ignition system, and no torque cones. Even tho I'm running the .600 cam I don't think the heads have been shaved and I'm not even sure if the cam springs were changed? But S&S says this would be the same kind of motor that BDM ordered except with a bigger cam. But before tuning the bike, on the first run I had about 108hp, when he finished I was at 123hp. The mechanic told me that the breather and exhaust pipe didn't like each other, that with no baffle that I was losing about 5 to 10hp. And I needed to change pipes, or get a tunable pipe. I love the loudness of the pipe I have cause I am a firm believer that loud pipes save lives, not to mention I turn a lot of heads with the sound of my bike. My question is what is your advise. I want the most hp out of my engine, but I honestly don't want to give up the loudness or sound of my bike. Do I change the breather, or do I change the pipe? Do I break down and have it bored, ported and polished? I don't want to sink a ton of money into the engine, and with the going from EPA to non EPA I already have over $3000 in parts and labor. But the mechanic says I should be putting out about 140hp. Is he blowing smoke or not?
you are not mentioning what the readings are on the torque side. with no baffles, you have no restriction on the exhaust, thereby loosing some torque on the low end. torque is what gets you going and horsepower is what keeps you going. more air through the intake is usuallly a very good thing but in turn, that means throwing more fuel at it also, which means worse gas mileage. but you still need some restriction on the back end. maybe a big city thunder baffle would do the trick for you without cutting into the volume much. think i would go with the BCT first and see if it helps the #'s first. and getting the heads done with bigger valves by John Sach is always a good thing, especially if you go with another intake. it's always a vicious cycle when you are chasing #'s, best to find a place where you are happy with the seat HP and stay with it.
Tom is absolutely correct! I just put a set of BCT's in my bike and holy crap what a difference! I actually slid them all the way in my Vance and Hines 2 into 2 exhaust until they hit the head pipe, then I installed my baffles that were cut in half at the tail end of the pipes! OMG! The bike has so much more throttle response it is ridiculous! I did try it also with nothing and it ran and sounded like crap, I am not a big fan of strait pipes, I like the loudness but when you let off on the trottle it makes it sound like those silly fish tail pipes that the low riders use! Lol! Definitely not my style! Anyway, the set up I have runs unbelievably good and is still very loud!
Yeah, that's for sure Eric, somebody asked me the other day how much horsepower my bike has? I was like, I have no idea and who cares! All I know is it freaking hauls ass!
If you want the back pressure for your torque AND LOUD pipes go to the Thunder Header! It 5+ bolt on HP! Sounds great and with the HP this pipe is loud and hell!
I am confused what you actually did to the motor? You say you spent 3k on parts from S&S to make it a non EPA, then you say all you did was a cam and didnt even change the springs? If you went from 108-123 there was something done.
John did instal the "Original Thunder Monster Baffles:" I ´ve got the "QQ Thunder Monster Baffles" Here: https://www.bigcitythunder.com/
The other issue is your carb does nor like your pipes, I had the same issue. Could never get my mid range jet correct with out the bike falling on it's face. I swapped to a Mikuni 45 and now it is a rocketship!!!
