True Dual setup

**JonintheRedZ28** · 07-16-2007, 10:07 AM

I'm looking to run a true dual setup on my 98 Z28, it's not running quite yet, but I got a short-block and a 228/230 cam, and I'm looking to have my car sound like the world is ending lol. Anyone have some suggestions?

**Rhinohuey** · 07-16-2007, 11:31 AM

I've been looking into true duals also, and so far the best deals I've found are just to have a shop make them. Either way, dumped or over the axle, I've found this to be cheaper than ordering something and having to pay for shipping, etc.

**JonintheRedZ28** · 07-16-2007, 11:39 AM

That's what I was probably going to do, since I live about 8 minutes from a muffler shop.

**aerojt** · 07-16-2007, 02:39 PM

Are there dyno numbers out there to show a huge power gain? I'm just curious if this is really worth it or not....I'm sure it its, just wondered what the actual gains are.

**JonintheRedZ28** · 07-16-2007, 02:44 PM

Well, I was interested a little more in the sound than the power gain, since the stock idle is so quiet, all the ricers where I live go after my Z, "It's quiet, it can't be a real V8" so I got a cam and am most likely going true duals, if my math is correct, (from the stock exhaust) true duals will add about 30-40 hp (on crank)

**Rhinohuey** · 07-16-2007, 04:20 PM

I don't think there is a huge gain with true duals over a catback, but there is definately a noticable sound difference.

**JonintheRedZ28** · 07-16-2007, 04:37 PM

Yeah, when I said true duals add 30 hp, I meant from the stock exhaust.
I want them more for the sound.

**StuntmanMike** · 07-16-2007, 05:19 PM

Look into a good 3" or 3.5" single exhaust. I read an article in hot rod a awhile back, they said a good single can flow just as good as a dual setup.

As far as being loud, run a cutout, or maybe the SLP Loudmouth. I haven't heard one in person, but from what I've read on the board, it's pretty damn loud.

If you get one custom done, make sure they use a mandrel bender, you don't want the kinked bends that hurt the flow.

I really don't think duals make any difference when it comes to sound, and unless you're going with headers, X-pipe, high flow cats, etc., I think 30-40hp is really optimistic.

**mrr23** · 07-16-2007, 06:02 PM

Originally Posted by Rhinohuey

I don't think there is a huge gain with true duals over a catback, but there is definately a noticable sound difference.

not huge, but definate gains throughout the entire rpm range

this is from the wife's car. had a 3" adjustable borla on her car with bassani headers and y-pipe. took the y-pipe and borla off and put the bassani tru-duals on. it comes with a x-pipe. this was on stock tune and stock cam.

**JonintheRedZ28** · 07-16-2007, 10:49 PM

A buddy of mine found a system (H pipe, mandrel bent) on LS1tech and I got in contact with the seller and paypaled him for it. Thanks for the input guys.
I'll post up a thread about the progress on my Z28 once I get back on it (I have to clean the garage and my parts first)

**ls1blackbeauty98** · 07-17-2007, 11:50 AM

when i was looking into TDs i was told that some fab had to go into them, which with me on a tight budget it was out of the question for me. i wasnt thrilled with the pipes dumping at the axle either, if u have the cash and dont mind the dump then go for it.

**9t8z28** · 07-17-2007, 05:53 PM

If you are gonna fab up a dual setup, go with an X-pipe.
H-pipes are old news and don't do as much as an X will.

**Rhinohuey** · 07-17-2007, 05:56 PM

H-pipe seems to sound a little better. X-pipe shows better gains though.

**9t8z28** · 07-17-2007, 06:02 PM

Originally Posted by Rhinohuey

H-pipe seems to sound a little better. X-pipe shows better gains though.

Yes, an H-pipe will sound more like true duals that never cross. But it wants it real loud, so I can only assume he is gonna have it dump before the axle. You will barely be able to tell the difference from an X and an H on a setup like that. Go with an X and increase throughout the entire RPM range.

**NvyBluMtlc02WS6** · 07-17-2007, 09:14 PM

Texas Speed sells a true dual set-up. Dumps before the axle and sounds bad ass. Debating on whether or not to get this set up or go with a y pipe with dual cutouts when i get my headers.

**JonintheRedZ28** · 07-18-2007, 02:34 PM

Originally Posted by 9t8z28

Yes, an H-pipe will sound more like true duals that never cross. But it wants it real loud, so I can only assume he is gonna have it dump before the axle. You will barely be able to tell the difference from an X and an H on a setup like that. Go with an X and increase throughout the entire RPM range.

Actually the TD setup I found is an over-axle setup.
The Z28's already going to be close to 400 hp, so I'm not too worried about a few gains from an X pipe over an H pipe. I got pacesetter LTs coming, heads from an 02, Comp XER cam. Like I said, I want the exhaust to improve the tone.
The cam is what I want to add power

the car's also getting dyno tuned once it's going. If I hit 380 rwhp I will be happy.

**9t8z28** · 07-18-2007, 03:47 PM

Originally Posted by JonintheRedZ28

Actually the TD setup I found is an over-axle setup.
The Z28's already going to be close to 400 hp, so I'm not too worried about a few gains from an X pipe over an H pipe. I got pacesetter LTs coming, heads from an 02, Comp XER cam. Like I said, I want the exhaust to improve the tone.
The cam is what I want to add power

the car's also getting dyno tuned once it's going. If I hit 380 rwhp I will be happy.

You found a TD system new or used?

**BULLET_WS6** · 07-18-2007, 03:57 PM

if you want to make it sound like the worlds ending.. i would have to recomend the tsp rumblers... i have heard those things on a car that runs a 6 second 1/8th... a little extreme yes... and a lot of the sound was coming from the high horsepower but that setup will let anysound you got come out

**JonintheRedZ28** · 07-20-2007, 12:59 PM

Originally Posted by 9t8z28

You found a TD system new or used?

Used.

**Wheeler99WS6** · 07-21-2007, 04:08 AM

TSP True duals for me. Docile at idle but Scream at WOT. I love em. No mistaking my car for anything under a V8. As MRRR23 showed you, its about 10-15 rwhp gain (TD setup) over a cat back.