Video - Rolling out of the garage, 1.4MB
Video - Revving (no load on the motor), 1.4MB
Video - Pulling past the camera (under load), 616KB

 

02thunder , I am glad you also think his tests are inconculsive.

 

The track gates opened at 5. Before the first run we had a 30 min. cooldown because the staging lanes were not opened yet.

The MAC exhaust was tested at the track versus the stock exhaust. The MAC system was tested first (which has had 4 weeks of ample break in time) w/ 4 passes w/in 15 min. of each other.

Approx. 1 hour later the stock muffler was swapped back AFTER the truck cooled down. A jack, a Sears Craftsman toolset, a mallet, and gloves were used to help faciliate the removal of the MAC and were used to help install the factory setup. The truck was ran up the road for approx. 10 to 15 min. to test for leaks.

The truck was brought right back to the line w/ no cooldown and 4 more passes were made on stock exhaust all w/in 15 min. of each other. We were pleased w/ the results. We we tired, left the track, and ate at Waffle House.

The temp. was w/in 1 degree I'm sure. We started in daylight, played in daylight and dark, and left when it was dark. Humidity stayed blanket thick all evening.

Enough of me trying to explain. I've noticed the ONLY two people upset w/ these test results, one resorting to basically calling me a liar, are the ones who promote the MAC exhaust or either want to install it.

walker887, is it just me or do you ALWAYS chime in on anything to do w/ MAC? Do you work for them or something? Sal couldn't even discuss the issues w/ MAC w/out you blasting him.

 

So basically you said you just ran a hot truck, hot lapped, with the MAC. Then you let it cool down, then ran the stock exacust.... Gee, i am no rocket scientist, but i would think a cooler truck would run better.

 

No, I stated that we let the truck cooldown for 30 min. BEFORE we ran w/ the MAC.

The factory exhaust was swapped back on and it was test driven for approx. 10 to 15 min. The truck was at operating temp. when it was ran during the 2nd round of testing.

The MAC 1st round of testing actually may have had an advantage because it was tested slightly below operating temps on its very first run. All 3 other runs w/ the MAC and all 4 runs of the 2nd round of testing w/ the factory exhaust were done w/ identical cooldowns...NONE! (if you want to call 15 min. between runs a cooldown).

We tested this way to mimic everyday driving and to make sure we didn't give either round an unfair advantage.

Anyhoo, who cares...

 

BfB,

Do you have the time-slips to prove what you're saying? Seems to me that if 'I' did a test that included 8 runs and an exhaust change-out, I would have the slips to prove it.

If you do have the slips, could you post them? There are too many variables included in runs to be conclusive unless you will allow us to see the slips. 60ft times, time of day, and such. The driver is the most important variable.

Most of the guys that buy the MAC cat-back aren't looking for more horsepower anyway, just a good sound and nice looking tips. Most are every day drivers that might race occasionally.

It seems that you just like to humiliate these guys and get a kick out of insulting their intelligence, but that's just how I see it.

Tim

 

If you change Exhaust on a lightly modded truck you may loose some power, thats true. But its not just a MAC thing. To get gains from Exhaust you need to be putting more power into your motor. (NOS OR ALOT OF BOOST)

This has been known for along time, so why is it any different now?

BFB,

I understand your test, thats cool, what other mods were on your truck during these tests??

 

BFB dont start this Sal issue again, that is between Sal and myself.

 

Well.............I never really got to do a baseline 1/4 mile run with my current mods, and the stock exhaust. My only run ever was bone stock, so when I go back to the track, I'm gonna show an improvement regardless, so my tests would be useless..........

All I can chime in with is my SOP feel...............All I know is that before, with 2 other people in the truck (180 and 120 respectively), I could not get the same 1-2 BARK that I could when I was by myself. At best I'd get a slight chirp..................Last night, with the same 2 people in the truck, I spanked the crap out of a friend of a friend's Civic TWICE. In the first run, on my 1-2 shift, the rear end got squirrely, and that was from a 10-15 mph roll...............the 2nd run was from a dead stop, and it got even more squirrely than the first run.....The same thing happened earlier in the afternoon when I ran the SKYLINE......it felt looser than usual (see my other thread on that race, somewhere in here)......the ground was not wet in both cases, and you all know how hot and humid it is down here. My guess would be that I gained a little up top..............down low it feels exactly the same.

My timeslips, as I said before, will be useless, because my only basis for comparison is a totally stock truck.............now it's chipped, filter, etc, so I can't really help, except for SOP feel...........sorry about your experience BFB.............I won't say it's conclusive or inconclusive, but in any case, it's what happened in your situation..............sorry to hear about your performance loss...........personally, after 100+ miles of driving it yesterday, I'm pleased...........time will tell if that feeling will go up or down.

JC

 

BfB, don't flatter yourself. Upset? Hardly. I was stating that the results are not complete. Argue all you want, I could care less. I do not have a Mac system on my truck, nor is one waiting to be installed. I am not one of those misguided people who thinks that a catback is a performance gain opportunity.

I have had my share of parts debate, and testing untested combinations when I raced Mustangs. So I am not gonna sit around and let someone DRAW conclusions, without all the data needed to support the theory.

Actually, I think I will, cuz it just doesn't matter all that much to me...

good night...
joe

 

Hummm didn't think this thread would get this interesting.. BfB is a massive data gathering machine. If what he says is true about changing mufflers at the track he will have the timeslips. If he does not post them they do not exist Even if he does post the slips(doubtful) does it really prove conclusively that the stock flows better? BfB it's showtime.

 

Thats my point genius. You stated that you let it cool down for only 30 mins with the mac, but over and hour for the stock.

Don't go bashing the MAC just because you have a hard on for Walker.

but who cares.......

 

Everyone is arguing about how valid the runs were. It's everyone knowledge that an exhaust cat-back on a L loses horsepower. A supercharged motor needs backpressure to produce horsepower. If the muffler scavenges extremely well it will kill hp. Guess everyone just likes to argue.

 

MiamiWhiteSVT-L, it is what happened in my friend's situation (it wasn't my truck), unfortunately for him. It may not in yours, and hopefully not, but regardless you're happy and that's what counts!

02Thunder, it's all good. No hard feelings. [extends hand]

Jeff, I need not prove anything. Why should I waste time on scanning in meaningless timeslips? I've already wasted enough on this thread. Timeslips will prove nothing to some much like my test data doesn't to some, just as you said Jeff.

It's like ICULOKN said:

If anyone wants the MAC catback let me know and I'll pass the info. along to my friend. It is for sale.

boostedtruck, you stated:

We did let it cool down for 30 min. before we ran the very 1st run. The 5th run (1st run w/ the stock exhaust back on), was only ran after the truck was driven around for about 15 min. to check for leaks. It was at normal operating temperature when ran, more so than the MAC's 1st run. How could this be considered a cooldown?

I'm not bashing MAC. The exhaust sounds awesome! I'm stating what I've experienced in terms of performance. Hardly a bash...

 

JP you do not have to prove anything Your the one who made the statement about the track. It's really hard and takes a long time to scan something and post it right? NOT! How much does he want for the Mac by the way? I know someone who might be interested :-)~