HMF Ecosystem exhaust

[kdanderson5]

I have an 04 660 that has HMF ecosystem exhaust from when I bought it. I was just reading on the HMF website and found this

"On average, the Ecosystem is making roughly 50% of the power as compared the the full open systems which is still a nice improvement over stock.
Dan/HMF"

This thread was talking about a utility quad. Any idea if this is true for a sport quad also? I would assume it is and I don't want to be getting raped of my precious power! 

All in all I an happy with the exhaust, it is loud but don't make the people behind me on the trail deaf which I am sure they appreciate. I just don't want to be robbing myself of power....I wonder what the difference would be with the quiet core taken out of the pipe if this is even possible? And if I did do this would it need to be re-jetted again?

Thanks for any answers!

Kenton

[Peelz]

Would be much louder, probably need a slight rejet, but, make 2-3+ more top-end hp. Low end, you might not notice it as much.

wide open HMF pipes are pretty loud.

[kdanderson5]

Hmmm. maybe i'll just leave it alone until spring then. I can live with it during the winter.

And peels, also being from Iowa, you know if there is any regulations in Iowa about db levels riding at the state OHV parks? I plan on riding some of them when I get a trailer so maybe it is better to have this pipe for that reason? I need to get a copy of the OHV park regulation book. It is a pain in the ass to read it online.

[kyledvor61]

Would be much louder, probably need a slight rejet, but, make 2-3+ more top-end hp. Low end, you might not notice it as much.

wide open HMF pipes are pretty loud.

+1 i had an HMF on my 350 and even with a quiet core it was f*ckin loud

[exentix]

Would be much louder, probably need a slight rejet, but, make 2-3+ more top-end hp. Low end, you might not notice it as much.

wide open HMF pipes are pretty loud.

+1 i had an HMF on my 350 and even with a quiet core it was f*ckin loud

+1 my 350 is pretty loud, its louder than alot of the people we ride with that have bigger engines than mine.

[kdanderson5]

I think ill just leave it alone then!   

[Krandall]

I've been trying to do some research. I found basically what Peels found. Looks like a redesigned Spark Arrestor to quiet it down.

I had an HMF on my 700 and the thing was FREAKING loud. It wasn't annoying loud. It had a low rumble @ idle and just barked when you got on the throttle! :grin_nod:

[Peelz]

Hmmm. maybe i'll just leave it alone until spring then. I can live with it during the winter.

And peels, also being from Iowa, you know if there is any regulations in Iowa about db levels riding at the state OHV parks? I plan on riding some of them when I get a trailer so maybe it is better to have this pipe for that reason? I need to get a copy of the OHV park regulation book. It is a pain in the ass to read it online.

sry, missed this post. Not sure About noise regulation, but I bet there is. I have yet to go to a state park here and ride.
I have no sticker on mine, it has never been titled. I only ride at private parks and out in the country.

Only rules I know about are Stay 5 ft from paved roads, and only ride on roads if crossing at a 90 degree angle. Or if for farm use, mount an orange triangle on the back. But...you try arguing that you need to go 75 mph while fully geared up for farming. "Them cows need hay real bad officer!"

[kdanderson5]

"Them cows need hay real bad officer!"

Maybe the cows do haha! When I am at home sometime I will try taking it out and see what it sounds like. I stopped by the court house here in Des Moines and picked up the OHV handbook. There is a lot of stupid laws and rules I was unaware of! Oops.  Good thing I didn't get caught!

I read through this loverly wonderful little handbook and it says you "may not exceed an engine noise limit above 96 db as tested under SAE J1287". I think this pipe is RIGHT under that limit if I remember right from random crap I have found online about it.

Thanks for all the help everyone!