true duels?

[thomas]

Is there any benefit to true duels vs the 3 inch catback? im looking at buying a set of longtubes from a guy and he also has a true duel setup that dumps before the axle for 150 bucks more. the thought would be to keep my borla muffler up there and when its time to run through insp in 2yrs hook it back up.

[ConElite]

Im sure Fred will come in, He knows much more about this but I think its like over 400-500HP then there is no use for true duals. Something crazy like that. If your just going to do bolt ons, Then No benefit but loose of ground clearance.

[Injuneer]

I never said there was no use for true duals.

A 3" catback isn't going to flow as much as a pair of 3" pipes with free-flowing mufflers. The question is, how much flow do you need? Maybe 2.5" duals would be adequate. A 3.5" catback or a 4" catback can support huge HP, with minimal losses. But if I was making 360rwHP, I wouldn't be limiting myself to a 3" catback. The Borla does help minimize losses with the open plate designs, but eventually, it isn't going to flow well enough.

The example I have cited in the past was a 97 SS making 1,125HP at the flywheel. Switching from a 4" Mufflex catback to the dual 3" design that is similar to what thomas is asking about did not increase the HP. It just saved 50# of excess weight. But that was a blower motor. An NA setup will probably benefit more from a well thought out true dual setup.

I'd never say true duals have no use..... since I run a true dual setup:

[ConElite]

I think you kinda misunderstood me. Its commen sense that duals will flow bette rthan a catback, but I was more refering to bolt-on applications. I dont really thing its worth it if its a bolt on car. I would say for $150 is not bad for the pre-axle dumps. Make that car really rumble. Only downside I think is the loose in Clearance.

[Injuneer]

He doesn't list his mods in much detail, but at 360rwHP I suspect it has more than an 0.030" overbore and bolt-ons. I could be wrong though.

[Craig 94 TA GT]

I'm pretty sure he has heads and cam. I think true duals may benefit because he's putting down around 430 flywheel hp. I have been told that my 3" Borla is a restriction, but I posted the question as well, and nobody replied as to how much. I would guess you could free up 5-10 RWHP with a dual exhaust system as long as the headers or cat aren't a huge bottleneck.

[Joe 1320]

If you want alot of resonance inside the car, then duals dumped just behind the axle will give you enough of that to give you headaches. I wouldn't suggest it for steet use.

My single 4" mufflex that I got from Fred after he switched to dual dumps, flows like a sewer pipe....... albiet makes some serious noise. the 2500+ rpm drone is pretty stout. I can't recommend it for street use in an automatic.

[Bananasaboutcars]

I read somewhere once that the biggest restriction on an F-body exhaust is first at the exhaust manifolds, second the y-pipe. That's where the bottleneck is. A dual system eliminates the crossover y-pipe that restricts air flow. Even if its smaller pipes, a true dual with headers should outflow a single pipe because of the crappy design of the crossover y-pipe. Consider getting a better y-pipe like SLP's or someone like that if you go with the big single pipe.

www.bananasaboutcars.com

[Al 96 Ram Air T/A]

Hey Peter...post some info. about your car(s) so we know what you have, and where your experience comes from.