just out of curiosity how restrictive are the two cats on the O.E. setup? (in comparison to the 2v of course)

 

Again, this part of the exhaust is not as restirctive as well-

This is what we have seen-

2v- catback- 14-15rwhp gain
2v- catback and X pipe- 24-25rwhp gain

3v catback- 11rwhp gain
3v catback and X pipe- 19rwhp

So the catbacks on the 2v are gaining about 4-5rwhp more then a 3v and the X pipes are adding another 9-11rwhp while only about 8rwhp on the 3v-

We tried all sorts of tricks to get more power out of the 3vs- but it just wasnt happening- I believe we designed and dyno tested about 30 different exhaust systems on the 05 before we settled on this one-

I also know via working trade shows with many of our competitors and having lunch with them (believe it or not-most aftermarket exhaust companies are actually pretty friendly with each other) we were not the only ones to spend more time then normal on this car-

 

Can you show us the test results? Specifically I am deciding between an off road h or x pipe. I have already decided on Long Tubes with 5/8" primarys.

 

Well it really depends on which X pipe you are going to use- some X pipes definitely work better then others-

I would definitely go with an X pipe/ straight through muffler combo though-

Some X pipes only give good gains in the top end over an H, but a well designed one will give you gains across the entire power band over the H pipe-

We make both H pipes and X pipes and after having both of them on my car- power wise- the X wins hands down-

Sound wise, its whatever you like- the H is more classic muscle- the X is more NASCAR- IMO sound wise-

I know many of the NASCAR teams do their own R&D work, and right now most seem to be running a Dr. Gas or a Magnaflow X pipe-

For comparison sakes- my idle jumped up about 150 RPM when I put the X in my 67 - because the car was breathing so much better, the idle went up- of course on new cars you wont see that because a computer controls the idle-

 

I know you have a little bit of inside knowledge. When is the magnaflow o/r xpipe coming?

 

Do you have some dyno charts for your 2.5" exhaust? I'd like to know how 3" is too big with the gaines I've received. Yes, I'm N/A currently but will eventually go to some poweradder. I didn't think 13 rwhp/13rwtq was too bad an increase.

 

I will provide you with several resources- this is the first-
http://www.magnaflow.com/05news/maga...0mustang01.asp
This was an article by 5.0 magazine-

We installed just a catback on a 05 automatic and gained 9-12 rwhp
(it is really hard to give exact numbers as you get a pretty nice power spike with the automatic)

That is not including the X pipe-



This is the dyno sheet for the X pipe and catback-
http://www.magnaflow.com/02product/dynos/15881.jpg

Someone changed the torque numbers on the right in the marketing department so they would match the numbers on the hp scale-

so on the right- the 280 should be 290
the 260 should be 270 and so on.......

sorry- sometime the marketing department tries to fix things that shouldnt really be fixed.......

we get those numbers by using the following procedures-

we check- humidity, temperature, intake manifold temerature, block temperature, exc

we then baseline dyno the car 5 times and run it with the Magnaflow 5 times making sure all variables are equel-

We throw out the highest numbers, the lowest numbers and use the median-

All dyno tests are run on a stock vehicle-

For comparison sakes, we claim 14rwhp on our 99-04 systems, yet many people have seen only 12rwhp gains- and the founder of www.corral.net saw a 16 rwhp gain on a stock 02 GT-

All of our testing is all done on a Dyno-jet dyno-

Ill see if I can find some more dynos as well-

There was one guy who got 12rwhp on a stock car with just a catback and had his dyno posted on the website- but that was almost a year ago so Ill have to see if I can dig it up-

Thanks
Brent

 

I cut and copied the post from the other site so you could see it-



I have had the chance to do the same install and the fit and finish is superb. I like the exhaust note and it is noticiably louder both insdie and outside but not obnoxious at all when driving. The Mustang had about 3000 miles on her when she was baselined and then the MagnaFlow 15881 kit was installed. Stock was 253 RWHP and 285 RWTQ. After was between 266-272 RWHP and 290-291 RWTQ. It was a noticable gain and you can see it on the charts but you have to be careful when reading the numbers becasue of the automatic. With the shift spikes it says peak stock power was 285 but in fact you can see its really more like 260-262 and after the exhaust it more like 285-290. The dyno seems to read the highest numbers which are not right. This car was a little tricky because of the 5 speed auto but the most consistant passes are whent he car is allowed to run at Full Throttle for the whole pass, otherwise you get some of these spikes and bumps like Nino said.

If you are looking for louder they have another "Magnapack kit" which has the 4" resonators and is really supposed to give it more exhaust note. I'm waiting to see if someone else gets one of these around here but what i have now is just about right.

Dyno from 2nd gear through 4th (full throttle)
http://home.earthlink.net/~rwaitas/...res/05speed.gif

Dyno of just 4th gear:
http://home.earthlink.net/~rwaitas/...ures/05gear.gif







Here is the thread itself- its towards the top of the second page-

http://64.177.72.121/forums/showthread.php...7247#post97247)


Im going to keep looking and see if I can find more dyno sheets for you-

 

Dyno pics aren't there

 

I do and dont' agree with the fellow from Magnaflow.

You are right in saying that a 3" exhaust is in reality overkill for the 2005 Mustang if it is stock. But we developed our 3" system because we know that a lot of customers will be adding superchargers, turbos, NOS, etc. As soon as cams come out we know that people will be going crazy with this.

With the same reasoning, why replace any of the factory pipes? It is 2 1/2", CNC mandrel bent s/s. We don't even offer a 2 1/2" system for the '05 Mustang yet as we opted to offer a muffler replacement kit. The factory was nice enough to give us a slip joint into the mufflers. We sell a pair of mufflers, tips, and connector pipes that if the car is completely stock or close, will make more power for less money than putting a complete cat back on. We may do some variety of manifold pipes, but have not gotten into that yet.

We designed our systems by spending a lot of time on the dyno. In theory, the 3" system should make less torque that the 2 1/2" system. In our testing it did not. We also sell 1 5/8" headers and 1 3/4" headers for the '05, and I thought for certian the 1 3/4" headers would KILL low end power on a relatively stock '05. It did not hurt it nearly as bad as I would have thought-about 3--5 ft# down low.

5.0 Mustang just did an article with our headers and confirmed what we tested. The setup is really overkill for a stock or even bolt on car, and you would think that a 1 3/4" header would hurt torque-not true. The car picked up 18 RWHP and 16 FT/# of torque with no tuning to optimize the headers (a reflash was done in the beginning of the article but not after each step). The overall gain was 41RWHP and 40RWT. The really impressive numbers will be when the next step of that project comes together.

So, if you are not going to change anything but the exhaust, buy a muffler replacement kit and don't bother with the factory pipes. If adding headers, bolt ons, etc, the 3" choice may be overkill but it will not hurt torque or horsepower. And if you add a lot more mods or a power adder later, then you are already set.

Lastly, the backpressure of an exhaust is dictated by the size of pipe, x or h pipe and its scavenging effect, and the muffler design. Pipe size alone does not determine what the exhaust velocity will be.

Thanks
Al
Stainless Works

 

So far, this sounds like a good, technical discussion (as apposed to name-calling) so I think I'll add my opinion.

First, I believe sound waves travel at . . . . .the speed of sound. The resonance point of the larger pipe is just at a lower frequency.

Second, the whole idea of needing back pressure to keep from losing low end torque is an old rule of thumb left over from the 60's when we had high overlap cams. Back pressure was what kept you from losing part of the intake charge out the exhaust when both the intake and exhaust valves were open. The modern car, due to EPA constraints, has very little cam overlap. This means that while you may not need the 3", it won't hurt you either.

And finally, diesels ared a whole different story. Larger exhaust help (to a point) by increasing the delta pressure (drive pressure) across the turbine side of the turbo. They run the best at zero back pressure.

The Boss Hog . . . . Just my opinion

 

Well-

we actually offer muffler replacements as well or axle backs as we call them-


The reason for a full 2.5" exhaust system is that there are several bends we are able to elminate in the factory exhaust system which results in an additional few hp-

Of course we decided as well to offer both-

Really I apologize I should have added a disclaimer in my original post-

All of the facts I provided were based on Magnaflow Mufflers-

Depending on the muffler, those numbers can definitely change- For instance if using a chambered muffler, the switch from 2.5" to 3" can be made much much sooner then with a straight through design muffler-

as a chambered muffler will not flow as well, so you will need to step up the size of exhaust in order to get the reduction in back pressure-

Talking mufflers alone, we have yet to be beat out in any shoot out-

www.mach1registry.com did a shoot out comparing several straight through design mufflers, and not only did we win, but we won by about 6rwhp-

Hot Rodding Engine Masters Challenge- the last several years the 1st and 2nd place winners have claimed to have made more hp with Magnaflow mufflers then any other available-

So, using Magnaflow mufflers, you are much more likely to see a loss in power by switching to 3" too early- as our flow rates are to this point unmatched-


I do have to admit though, when it comes to cars with crazy power, we do not build any systems to target that market- while your 3" system does-

Realistically from a full system point of view, we are not really competitors in my eyes-

You are building exhaust systems for fully built project cars (stroked, supercahrged NMRA fun) - we are building exhaust systems for stock to bolt on cars like Saleen, Roush, Steeda, and so on-

It seems we each have our niche- with our competitve area being that person who has built a car that is more then a bolt on car, but less then a full out race car- as they could go either way-

Out of curiousity though- do you guys build short tube headers that would work with say- our X pipe and catback-

We get alot of people who ask if there is a header we recommend to use with our X pipe and catback- and up to this point I have had nowhere to refer them too- and its always good to know as the only ones I know now are JBA and BBK-
(and those guys at JBA are always trying to switch them over to their full exhaust- maybe you guys will be nicer to us.....lol)





Edit- Boss Hog- the only real problem we see on diesel is that when you step up on the down pipe too much- you can cause the power band to move as the turbo will not spool up as fast-

we suggest a 3.5" downpipe for most applications, however we do offer a 4" downpipe for those with turbo upgrades and so on-


BTW- We in the aftermarket exhaust industry are usually pretty cool with each other- you would probably be suprised at the number of drinks I have bought for Flowmaster/ DynoMax/ FloPro reps and the number or drinks they have bought for me-

when it comes down to it- we are all just trying to make a living- no need to get in a fist fight over a few car parts if you know what I mean-

 

Very interesting discussion since I am looking at headers/exhaust to go along with a blower going on next month.

Is there a certain level of boost/hp where a 3" exhaust would outperform a 2.5" exhaust? I am currently planning on a mild level of boost (5-9psi) and I am unsure what size long tubes (1 5/8 vs 1 3/4) and exhaust to go with. I would like to keep the torque as high as possible.

 

Really you could go either way-

Both Stainless works and ourselves are going to have our reasons why you should go with our system-

it will be up to you to make that choice as you are pretty much right in that are where we would be competing against each other-

Maybe Stainless would be willing to provide you with their tech number, and I will give you mine- that way you can get the facts from each of us and make your decision-

I think that would probably be the best way-

 

Seriously, it sure seems that the exhaust companies get along better than other realms. As far as 3"...I'm happy with my numbers and don't have to worry when I go to a poweradder.

 

So if I plan on supercharing later, do I need a 3in or with the 2.5 be fine?

 

That's a very good idea

 

http://www.stainlessworks.net/cart/index.php
9899 E Washington St.
Chagrin Falls OH 44023
(800) 878-3635 or (440) 543-6593
Fax: (440) 543-9183
E-Mail: info@stainlessworks.net

Al is the owner.

 

I dont know about that Dave.I still have the factory Manifolds,cheasy steeda CAI,still have factory charge motion plates.stock gears and the 2,1/2 exhaust and I am making the same power as you are with all those extra mods.3'' could be keeping your torque down than where it should be. :scratch:

 

MPH is Horsepower.We are basically the same.Your ET reflects your 60 ft wich I have no suspension mods yet.I am going to run my car right into the 11,s before I change headers,suspension or charge motion plates.Yes this will be on NOS but I bet I can do it.
I have been closely watching how your mods work.I did just get the 4:10,s Installed and have not even driven it yet.But I garantee this mod will bring me right up to your ET.My 3.55s were giving me a slight bog off the line wich I still ran 13.0 but,I have the MPH to get in the twelves.I would never go 3".some backpresure is horsepower but our little 4.6s unless supercharged dont have the cubic Inches to warrant 3'' inch.