KurtRardin

iTrader: (11)

Im soon to put my LTs on and I have a LM with the resonator. Which of the two (dyno and borla) makes has the most back pressure? Im looking for sound too, because i hear that an un-cammed LT'd LM'd LS1 car doesnt sound too great. I plan on going with an ORY, so i need some back pressure without getting another Cat-back all together.
Thanks

SouthFL.02.SS

You don't need backpressure. Backpressure kills power.
All backpressure does is make tq. available sooner at a handicapped number, thus tricking you into thinking your car is faster.
Free flow gives you MORE TQ, it's just available higher in the rev range.
Don't choke up your exhaust.

Borla XR-1 and Dynomax bullets both flow incredibly well.

300bhp/ton

yep I agree, you want minimal back pressure, espcially if you plan to do more mods and tune. As for working it out, you need to find the flow rate for the mufflers. Check out the sticky about mods, I think post 13 or so, the section by David Vizard is what you want to read, it'll explain it all so that you can go and decide for yourself which muffler to get and why.

Benjamin Russick

iTrader: (1)

Meh. I had the DynoMouth and it sounded like crap. The Borla XR-1 that I replaced the bullet with completely eliminated the rasp and made it sound 1000x better. It's well worth the $100 IMO...

Redneck Z

iTrader: (3)

Like everyone said you don't want more backpressure. Don't worry about flow #'s because they are both straight through and will flow all the air you ever need to flow. Backpressure and flow will be essentially identical between the two.

300bhp/ton

straight thru doesn't always mean they flow the same. If they are glasspack then they appear like a cheese grater inside which is then packed with glass fibre, as gas expands it will pass through the glass fibres thus effecting flow. Glasspack mufflers also effect the exhaust pressure wave which can dramtically affect horse power. Chambered mufflers can also be straight thru design such as Powerstick and Stainless Wroks classic chambered mufflers. Fluid dynamics is not as simple as a quick visual observation.

gwj

If given a choice for a substitute for the resonator on a
LM, you can't do any better than an XR-1.
Whether or not you will like the sound, well, no one can tell
you that.
Loudness with an M6 / Borlamouth is even less of a
factor than it is with an A4/2.73s/3500 stall like I have.
....and so far I'm happy with mine since 48K miles
(see sig).

KurtRardin

iTrader: (11)

Thanks for the info. How about the LM muffler, or the LMII that i hear about? They sell that muffler for about a hundred bucks.

Redneck Z

iTrader: (3)

Who said anything about a glasspack?? I know what a glasspack is.....Oh and thanks for the quick lesson on fluid dynamics LOL! This post is about the straight through borla and dynomax bullet. The flow and backpressure are essentially the same.

Redneck Z

iTrader: (3)

I'd rather buy the dynomax bullet. It's basically the same thing, only cheaper.