Have you ever used a set of LSR 2 into 1 exhausts? They talk a lot about the sound waves and gas speed and temp redustion. What's your opinion on their products? Thanks

We've used them and had good success with them, they're not bad. And we're a dealer for them. They diffuse over a wide range and have low pumping losses.

I took them off the website though due to customer frustration with their delivery times. We'd order a pipe for someone and it'd take 2 months to get it. And of course the customer hollers at us. Not worth the aggravation.

I posted a similar question about the pipes. Would you reccomend a set for your 1250, stage 3 XB heads, .536 se cams, dyna 2000i ignition, kit on a 2003. Performance wise how would you say they match up next to a Thunder header, or a set of Bassani pro steets. I'm ditching my exhaust and would really like some advice on my next purchase. I'm having a hard time finding a pipe that performes well and looks good too. Thanks in advance, I know you guys are busy.

Lucky, the way I think an exhaust ought to be done is to diffuse without introducing back pressure. A good example of thisis the big-bore Force system that we offer:

http://www.nrhsperformance.com/partsexhaust.shtml#Force%20Exhaust%20Systems

My M2 (in the picture) uses one of these and makes over 120rwhp at 1250cc on pump gas. But I'll be honest with you, it's a less popular piece in the Sportster line and cosmetics has a lot to do with that.

The Bassani Road Rage, like SporsterSpive Sean has, is a nice piece too, and the baffle can be removed and it still diffuses nicely, at least that's been my experience.

If you've got to have a backpressure inducing device to get your diffusion, well, I'd say either Cycle Shack or Supertrapp is the way to go. I like the Supertrapp because it's adjustable, you're not stuck with how it's working for you if you don't like it, and a number of our customers have gotten over 100hp results using them with broad powerbands, so their pumping losses aren't too bad.

ASWR:

I have a set of Bob Johnson's heads, a set of one off Andrews N3s, Twin Tech TC88a, Cycle Shacks, 10 - 1 wiseco 883/1200 conv pistons and a BT round K&N filter set up.

I'm not looking for a 6000+ motor, hence then N2-N3 cams. Depending on what the dyno shows we may put N2 exhaust lobes in to get the duration back. He gets great power with the N2s. The N3s made more torque than the N2s did and did it 500rpm's sooner with only a 1 HP drop at 6250.

Cam Specs; 480 lift, 240 I, 236 E, I 22-38, E 42-14, Basically they are N2s with a bit more lift and less exhaust duration.

N2's made 84HP at 6250 and 79ft lbs at 4500-5000
N3's made 83Hp at 6250 and 81ft lbs at 4000-4500

These numbers were with 04 1200 heads. I currently have a set of 04 883 heads done the same way but with 1.715 I and 1.480 E that I will be putting on as soon as the snow and slush goes away. Numbers to follow once they are on. I wanted the 883 heads for the smaller ports. I'm hoping that the increase in velocity will increase my low to midrange power over the 1200 heads.

I am not second guessing Bob, I think he is great, but always looking for another honest opinion from builders. The more info you can get the better choices one can make.

Would a T-header or an LSR be an improvement over the cycle shacks? Or maybe one of your force pipes?
Do you have a photo of one of those force systems on a sporty?

All these pipes are expensive and buying the wrong one would be costly.

Thanks for any info you can share. Barry

Tell you what I think you should do ... look at dyno sheets. We've got a pile of them on our web site, so do several other companies. What you want to look at is the shape of the torque curve, not the size. A torque curve is basically a map of the cylinder fill. When you get exhaust augmented intake flow (overlap coupled with properly timed negsative pressure wave from the pipe), it causes a bump in the torque curve. Nine times out of ten, the torque peak on a dyno sheet is the rpm at which the exhaust is pulling the hardest.

When you look at a bunch of torque curves this way, you quickly realize that pipes are all over the map. Some pull hard at one rpm and give it up everywhere else. Others pull softly but do it over a wide range. Some pull up high, some pull down low, some in the middle.

Occassionally you see charts with two torque peaks. This is more common in 2 into 1's than 2 into 2's due to the additional source of pressure waves for each pipe (the other pipe), but it can be done in 2 into 2's as well if they're stepped and the steps are placed for it. I once designed and built a 2 into 2 that literally gave 3 torque peaks. It's a technique a pipe designer can use to broaden the rpm range without weakening the wave excessiviely. It can also be a sign of a bad marriage between the pipes and the cam, though, a pipe that pulls at one rpm with cam timing that works at another rpm.

Anyway, that's the way to do it, look at the torque curves that come from various pipes and choose the one that suits your goals. I'll say it again, too, the Supertrapp is not a bad way to go, because if it's not working at the rpm you want it at, you can adjust it, you're not stuck with it. It has some pumping losses so it's not as efficient as a good unbaffled reverse cone megaphone, but the adjustability can be worth it's weight in gold.

Thanks for the tip