Pypes 2.5" x pipe, street pro vs. race pro mufflers
 

I'm undecided on which muffler to go with & am looking for opinions/experiences.. I'm leaning towards the Pypes 2.5" x pipe system on my 69 T/A, stock RAIII. To me, the stock exhaust system seems too restrictive, and I feel this motor needs to breathe.
First; has anyone experienced any issues with this type of system on their 69 that I should be aware of, and second; it's got to sound good and be responsive, but I don't want it to be too obnoxiously loud.
Any guidance that can be offered would be greatly appreciated. I'm at the point in this build where an exhaust system purchase is in my near future, and I haven't committed to the Pypes system just yet, so I'm open to all suggestions. Thanks.

I went with the Magnaflow system. (The downpipes are Pypes). After a lot of research, it was obvious to me that the Magnaflow exhaust pipe design was going to get the pipes and mufflers to tuck up a lot closer to the floor and have better ground clearance than the Pypes system. I hate exhaust systems that hang down low. Been there and done that.
Take a look at my install starting with this post in my build thread. Follow it through post #620.
https://forums.maxperformanceinc.com/forums/showthread.php?p=6319662#post6319662

As far as how they sound, I'd say just like what you describe you are looking for.

Edit:
Oops. I read too fast and see now you have a T/A and not a GTO. So the fit might be different for your car with either system.

I went with the RacePro mufflers on my twin 2.5" X-pipe system. Not only were they the best flowing, they were the 'quietest' of the Pypes range. And having said that, exhaust is still loud and close to obnoxious. It says a bit for the other mufflers! Car hasn't been on the road since to know how loud it is driving, but it is loud just idling. Will likely require muffler replacement prior.

FWIW, I replaced the Pypes MVR36 (3" x 18" case, no longer available) mufflers on my Cutlass with 17547 DynoMax Welded UltraFlows recently.

I used to cringe when I gave the Cutlass much throttle, as the RacePros sounded like the cheap glasspacks the rednecks in high school put on their trucks. Maybe the pair I had were made without the correct amount of packing or something, but they sounded horrible to me. I have Borla ProXS on one car, and the UltraFlows on another - the UltraFlows sound the best overall to me.

If you want it to appear correct there is only one muffler offered with the Pypes transverse setup. They use the Racepro design on the SGF70 kits.

I've used about 6 of these systems now, 2 of them currently on my own F-bodies. Not loud at all, no drone, fitment is good, with a nice mellow tone while cruising, but does get a little louder at WOT.

Here's my bird with the SGF70 system.

outside the car
https://youtu.be/er1z7PpqsnY



Inside the car
https://youtu.be/XqEydRRRwqE

As far as performance differences it's pretty substantial over stock. Been racing this car in PS form for 25 years and started with a stock Gardner transverse system where the car was stuck at 14.0's at 99 mph. Have had 2 different 2 1/2" transverse setups on the car since, one a flowmaster Force II (no longer made) that immediately picked the car up to 13.60's at 102 mph and then the Pypes SGF70, and with this system in place it's gone a best of 12.89 at 106 mph.

As far as I'm concerned these F-bodies look best with a factory style transverse setup as they were intended so I don't even consider an A-body style dual muffler system. But if that's the route you go it does open the door for more muffler choices. If that's the case, I use and prefer Dynomax Ultraflows and have those on a couple other cars here. Nice sound as well, not obnoxious at all and have no drone to deal with.

Another alternative that I've done (been many years) on a couple of X-bodies I had that uses the same transverse exhaust setup is use the old 89021 thrush/dynomax transverse exhaust system.

It's not stainless and doesn't have an "X" cross over, but is aluminized mandrel bent 2 1/2" system with an "H" cross over. Then what I did is substitute the stockish transverse muffler (that honestly doesn't sound bad) and replaced it with a Dynomax Ultraflow transverse muffler.

I have the Pypes transverse muffler kit and hate the way it sounds. Even with long tubes and no cats it sounds like a toy.

I will be changing this system in the future

What does a toy sound like?? :confused:


Got any sound clips?

Here are some other SGF70's that I installed

https://youtu.be/AOqwz3QlO5k

Same car inside ride along
https://youtu.be/Iesvy0R3isA

Our Z
https://youtu.be/5dTNw93VPEQ

my Sprint
https://youtu.be/47HgejCVbFs

I have the Pypes 2.5" x system on my 69 bird.

From the headers to the mufflers, the fit is excellent. The fit of the over-axle pipes leaves a bit to be desired.

I originally ordered my setup with the violator mufflers. It was cool at first but I grew really tired of the sound. It was blatty and always screaming at you. The RacePro's are supposed to be fairly tame until you step on them, then they get about as loud as the violators. Both of these mufflers will have a decently high pitched sound to them. The StreetPro's don't flow as well as the RacePro or the Violator, but will sound more like a traditional turbo muffler.

Ultimately I removed my violator mufflers in favor of a magnaflow muffler it it's place. They're virtually the same dimensions, so I was able to make that work easily. The magnaflow mufflers have a much smoother and rounder tone. Still probably not for everyone, but much more to my liking.

If you're after that classic muscle car sound, I'd stay away from the Pypes or Magnaflow mufflers in favor of a dynomax or flowmaster kit. Those will give you that more classic sound. The dynomax kits should flow around the same as the pypes kit with the streetpro mufflers.

So you put a dual muffler setup on an Fbody and not a transverse? I have no experience with the Pypes fitment on Fbodies in that configuration, only the transverse.

On the dual setups I've never used the Violators, just the name of those keep me away, lol. I do have the racepro mufflers on one dual exhaust setup here and they are actually extremely quiet behind a 350hp 327 with headers. On this particular car they sound more like a quiet turbo muffler setup. It is however a very long exhaust system setup with longer than normal tail pipes.

I had a magnaflow on a 4" exhaust setup years ago. That was loud everywhere all the time. I like the sound of them on a smaller 2 1/2" system though.

In other words, sound is really going to change depending on how you have the exhaust configured as well as engine characteristics. Just listening to the same SGF70 I posted above on 4 different cars, each has their own sound.
The Z I posted got even quieter when I grafted in the factory 2" 69 camaro style tail pipes for a stock appearance.

I've always liked the flowmaster sound but damn those things cost HP. Those chamber mufflers are just not that great for flow. They sure sound good though.

Correct, I do not have a transverse system on this. The mufflers go in the same place that the factory resonators would have been, so the fitment is not bad. My car is very low and the mufflers do not scrape.

The Violators are designed with cups that intake exhaust gases into the muffler packing. The opening of those cups or scallops face away from the exhaust flow. At any real amount of throttle they become essentially a straight pipe. The Magnaflow mufflers that replaced the Violator mufflers are probably 30-40% quieter in all situations, but you still definitely hear them. A super turbo muffler is likely quieter.

And you're absolutely correct about each car and configuration being different. I currently have a set of three tube headers on this car which I believe make the sound a bit higher pitched as well.

Speaking of headers, I've swapped back and forth on my Firebird between 4 tube Hooker super comps and the factory RA exhaust manifolds. I actually liked the sound of the SGF70 on that car with the headers, it was smoother and more refined. When I put the factory RA manifolds back on the car (which is what is in those videos) the exhaust actually got a bit louder and a little more raspy sound to it.

Anything with a decent scavenging effect will certainly smooth out the tone a bit by nature.

Thanks for all replies. I failed to mention I'll be using the original long branch manifolds.
Decisions, decisions.....

What does a toy sound like…..

I’m at the airport so I don’t think I can upload a video but if anyone wants it PM and I should be able to text or e-mail one.

The car has a definite Whirrring sound. Remember the toys you would push 3-4 times real fast to get them going and they had that artificial sound? That’s it.

I had a grip/handle on my bike as a kid you would rotate to spin and it would make an engine sound. That would be it.

We put the headers and exhaust on it- all excited to hear and then we just were like ‘oh. So that’s the sound.’

Buddies that new I put on the exhaust were like let me hear it and you could tell by their reaction every time- ‘oh, well it’s not bad.’

I think it was like $1000 for exhaust, $200 for tips and $600 for headers. I was hoping for better than ‘ it’s not bad’.

To be fair- I’m a flowmaster guy. I like that sound. this is also a stock 403 so i didn’t expect any cam sound.

My 69 GTO with log manifolds and flowmasters costs less and sounds better.

Pypes has videos with the different mufflers to listen to. I went with the turbo pro and X pipe.

I am still trying to decide on my 2.5 inch exhaust 68 firebird convertible. Either the Pypes X system with transverse Racepro muffler, or the Thrush H-pipe system with Dynomax or Magnaflow transverse muffler. I wonder which one fits easier with the convertible frame brace.

I haven't personally installed one on a 1st gen vert, but I've seen the Pypes SGF70 on a convertable. It tends to have a little more flexability with the "X" design because the pipes in and out of the X can be manipulated in such a way that you're able to tuck it up pretty much as tight as needed, and the X can be moved forward or backward depending on how you trim the pipes.

The H system is a little less forgiving in that regard.

I do like the Thrush/Dynomax system though, for the price it's really hard to beat, fits good and sounds good.

Sorry to drag one back up.

But does anyone have any testing for the practical max HP limit for a transverse system vs a conventional dual muffler setup? Thinking all 2-1/2".

I need to do something with my 1st gen Bird and I really like the transverse design. Just don't want to give away a bunch of power everywhere. Not a big deal way up on top for me as I am rarely spinning it that hard.

Dave

i just took the transverse out and put in duals. I did it because i put a 8.5'' posi rear in it and it had a fancy diff cover that has the bolts to keep the caps from moving and on my car, 69 firebird, it would hit the muffler when going over some bumps, and it was very annoying.
I took out a dynomax stainless cross flow and installed pypes street pro muffs and flow master tail pipes all 2.5'' It def feels a little less corked up but i have the ram air d port manifolds on it so those are probably holding it back a bit more than the cross flow. It did go 12.80s at 108 the other night so its healthy but not a race car.
i had the thrush h pipe exhaust tucked up super high where you almost couldnt see it unless you were on the ground. this is a bit lower off the floor but not too bad.