89 Coupe, A/T, mostly stock motor for now...even when I build teh new
motor it won't be all that nasty, maybe ZZ4 region.

What I'd like to do, is something like Melrose or TPiS headers, true
duals, x-pipe, B&B muffs, etc....

I'm trying to think in term of low resonance, but decent flow....

Oh, I'll be running a 100hp shot of N2o soon....

 

i got a auto 84 but heres my setup.

Eagle longtubes,x-pipe to magnaflows with challenger tips.

 

That's a good looking set-up that by itself would offer a nice performance boost, particulary on an earlier C4. I've never heard of Eagle headers for a C4. Are they specific to the application?

You're definitely on the right track M. Hall, in wanting to go true dual while you're at it. I've never been able to understand maintaining the large single cat system when upgrading an L98 car. The Melrose system looks appealing because of it's entirety from one manufacturer making me think that it should be a breeze to install. Stainless Works too is now offering a complete system from headers on back, even including mufflers in their case, if desired. If it's anything like the SW headers, cats and connector pipes that I'm currently using, fit should be excellent and installation pretty straight-forward. It doesn't sound as if you are afraid to spend a few bucks to get nice stuff. But for those with early cars and on a tighter budget, a set of Hedman Elites for around $400 and a factory LT1 (or LT4) exhaust system, either stock or modified, would also offer very good overall benefits. These systems are offered frequently in the f/s section either free for pick-up or at low cost. With headers and the resonator removed and replaced with an X or H pipe, they sound real good but not overly loud. And resonance won't be a problem at all. The only difference between LT1 and LT4 systems is that the LT4 one already has an H pipe installed, but that's an easy thing to remedy if using starting with the LT1 system. With an inexpensive pair of Pypes or Dynomax bullet cats and an exhaust shop's help to fit it all together, I believe that the entire system from headers on back could be put together for $7-800 if one can do most of the work their self.
This concludes my lesson this weekend for our newbie friends, on the ever popular subject of exhaust upgrades!

 

What mufflers have you installed??

I assume that this is a "off-road" car only? The CA smog police might put your car on their "Most Wanted" list with true duals, no cats and headers.

 

eh you should see some of the exhaust systems ive ran before. haha my car b4 this one was a pretty big cammed li8ke no exhaust 95 lt1 camaro.

 

I went with EM long tube headers, a pair of high flow bullet cats, X pipe all put together with 3" stainless from a local shop and into stock LT1 mufflers. It did not make much difference in performance on my LT1 but from what I hear it should be a big boost on an L98. As far as sound goes it is about the same volume as stock just a little deeper tone. Should sound sweet after this winters head and cam upgrade.

 

Nice ideas thus far, keep 'em coming please!

 

My 89 Has a custom bent magnaflow exhaust similar to the one that C4Cruiser is running....

As far as the Magnaflow mufflers go... the exhaust system sounds awesome. The headers are really nice too.. they are Heddman Street Jet Coated Headers. I can see a huge improvement as far as lower engine temps.

Unfortunately the Jerkoff that installed the system didn't do what he said he was going to do, and to make matters worse, he couldn't weld to save his life. After just about 6k miles on the system it has been back to the shop twice. The first time they forgot to bolt the headers to the exhaust system so the exhaust fell off the car while I was driving it. Now all the welds cracked apart so the system leaks everywhere... needless to say I am going to have to take the exhaust to a competent shop to have the system tweaked. Oh and lets not forget i asked for a mandrel bent system... they said they did, but you will notice that, the didn't.

Anyway... the setup (i designed) is nice... noticable sound and performance improvement.. when i get it all tweaked it should be perfect.

DG

 

For a fairly mild budget setup on an '89, I'd buy the hangers and put an LTx setup from a '92-'96 on there. It's a good quality system for an L98 and can be found dirt-cheap. You could also upgrade from there to some aftermarket muffers (magnaflow, dynomax, etc.) for more sound and/or long-tube headers for added punch.

Melrose, exotic muscle, etc. systems are very nice but have the cost to match. I personally wouldn't spend that much unless you want the extra bling of a nice shiny stainless exhaust.

Are emissions a concern - tailpipe test or visual insp?

 

This is what I am in the process of doing. I just got finished (today, actually) pulling my Borlas off and am now getting ready to install an LT4 exhaust that I found in almost brand new condition. The resonator and stock mufflers flow nicely and should cut down on the resonance (and noise level ) that I had before.

 

Well,... glad to hear it is up and running. Are you installing the exhaust or do you have a guy to do it?

DG

 

Doing it myself Took the last ride of the season yesterday, put fuel stabilizer in, put it up on jack stands and pulled the exhaust today. We'll have to hook up in the spring!

(Sorry to the OP for getting off topic)

 

Cost really won't be teh main concern, and I've applied for emmisions
exemption, so that won't be either. I do want teh Billy Boat mufflers,
but I'm wondering how bad teh resonance will be with either teh 2-1/2"
or 3" tubing.

 

I dont think the tubing size is as important as how the muffler itself resonates the sound. Seems like the way our engines are setup, the chambered mufflers produce a ton of droning while the "glass packed" mufflers seem to eat the drone up a little better. My advice would be to look for something packed. Borla is loud and drones... Flowmaster was terrible on my 89, I like the magnaflows personally.

DG

 

I have Flows right now, and they are teh suck....

 

I see this all the time... I routinely talk clients OUT of Flowmasters when they come in the shop. The rationale is this: if you have some higher compression and a high-lift camshaft (good lumpy rough idling one), nothing sounds better than Flowmasters. If you have a stock engine (99% of people do), then Flows sound hollow and tinny. Listen to a typical Mustang and you'll see what I mean.

Magnaflows sound wicked with longtubes and true duals..