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Topic Review (Newest First)
11-28-2011 12:10 PM
Mr. Sinister
Quote:
Originally Posted by bo9roadking View Post
All of the 2012 JKs have the wierd bugle exhaust loop. The aFe exhaust does not replace the loop. It is installed after the loop.
gotcha, thanks.
i still want to know what happens when you remove that loop. it's only a matter of time, i'm sure.
11-28-2011 11:18 AM
bo9roadking
Quote:
Originally Posted by River Hill View Post
If AFE can pull another 20HP and 20lbs of torque using just an intake and exahaust, for those of us with a 2012, we will have 300HP Jeeps.
Yep, 305hp/280tq.
11-28-2011 11:08 AM
bo9roadking
Quote:
Originally Posted by sonofboxster View Post
Jason at aFe replied to an email I sent asking for estimates as to total increase with all three parts (intake, y-pipe, and cat back), and which does what. He said OK to post here:

--------------------

Thanks for your questions and interest. We are going to dyno the exhaust in the next week or so but here are my estimates.

The intake by itself made 12hp and 13 lbs torque. The exhaust by itself should produce about the same results. However, when put together these units will not produce a combined result as the first modification usually produces the best result and then it reduces as your add on as it is harder to make more changes. With intake and exhaust all in, I would expect around 20hp and about 20lbs of torque.

The Y-pipe will not produce on its own a huge amount of power, it was primarily designed to work with lift kits where the stock Y-pipe gets in the way. It will help keep the velocity up and improve throttle response but on the dyno it won't produce huge numbers.

The final link in the chain is a programmer. Once we have cracked the code and developed a tune, that unit should add another 15-20hp (est.).

Thanks again for your interest and we hope to have a video up and running this week on the intake dyno test. It has an exhaust on it so you can hear the exhaust.
That is good news, but I'd like to see confirmation. If they are saying the 20hp/20tq numbers are improvements over the stock setup, they haven't shown that dyno chart. The dyno chart on the aFe webpage for their CAI clearly shows a 12hp/13tq improvement with their CAI, y-pipe, and cat-back exhaust installed and working together versus a stock intake that is also running their y-pipe and cat-back exhaust. It appears that the CAI provided the 12hp/13tq numbers, but how much more if any did the exhaust improve performance? 8hp/7tq? If aFe could post the dyno chart of the fully stock dyno run that shows that their system provides 20hp/20tq improvement, that is what I'm looking for.
11-28-2011 10:51 AM
bo9roadking
Quote:
Originally Posted by Mr. Sinister View Post
So, did your 4 door had the weird loop in the exhaust?
I assume the new exhaust doesn't have this loop?

I've been curious how the new engine would react to having the loop taken out of the exhaust.
All of the 2012 JKs have the wierd bugle exhaust loop. The aFe exhaust does not replace the loop. It is installed after the loop.
11-28-2011 10:50 AM
River Hill If AFE can pull another 20HP and 20lbs of torque using just an intake and exahaust, for those of us with a 2012, we will have 300HP Jeeps.
11-28-2011 10:39 AM
sonofboxster Jason at aFe replied to an email I sent asking for estimates as to total increase with all three parts (intake, y-pipe, and cat back), and which does what. He said OK to post here:

--------------------

Thanks for your questions and interest. We are going to dyno the exhaust in the next week or so but here are my estimates.

The intake by itself made 12hp and 13 lbs torque. The exhaust by itself should produce about the same results. However, when put together these units will not produce a combined result as the first modification usually produces the best result and then it reduces as your add on as it is harder to make more changes. With intake and exhaust all in, I would expect around 20hp and about 20lbs of torque.

The Y-pipe will not produce on its own a huge amount of power, it was primarily designed to work with lift kits where the stock Y-pipe gets in the way. It will help keep the velocity up and improve throttle response but on the dyno it won't produce huge numbers.

The final link in the chain is a programmer. Once we have cracked the code and developed a tune, that unit should add another 15-20hp (est.).

Thanks again for your interest and we hope to have a video up and running this week on the intake dyno test. It has an exhaust on it so you can hear the exhaust.
11-28-2011 07:17 AM
Mr. Sinister So, did your 4 door had the weird loop in the exhaust?
I assume the new exhaust doesn't have this loop?

I've been curious how the new engine would react to having the loop taken out of the exhaust.
11-27-2011 11:38 AM
sonofboxster
Quote:
Originally Posted by bo9roadking View Post
I like aFe's products and I am glad that they are ahead of the game getting products out for the 2012 Jeeps.

The point that I was trying to make is that if someone wanted to buy the CAI, they don't know if they will actually see that hp/tq improvement because they might be running the stock exhaust. The way aFe has written the CAI description on their webpage, it appears that those numbers are available just from installing the CAI, but the published test results didn't use the stock exhaust. In order to get those numbers, you need to buy the CAI and the exhaust according to their dyno sheet. For the test to be of any benefit, there should have been at least 4 published sets of numbers.

The first dyno run should have the stock set of numbers to establish a baseline for all of the other tests. We know what Chrysler says the hp/tq numbers are for the engine, but I haven't seen what those numbers are at the wheels. The second dyno run should have only included the CAI to see what improvements it brings. The third test should have been only the exhaust/y-pipe. The final test would be what aFe has done, which is testing their entire setup. Of course you could have additional tests with different configurations, but I think those should have been the major ones.

By only publishing the test using their exhaust/y-pipe with and without their CAI, we don't know if the CAI provided the 12hp/13tq numbers or if the exhaust has also helped. It looks on the surface that the CAI provided all of the benefit, but why didn't aFe publish the CAI with the stock exhaust. I'm betting that those numbers were negligible because the stock intake and exhaust were too restrictive. If that is the case, the only way to see a real improvement is to replace both the intake and the exhaust because replacing only one adds no measurable difference.
Yeah OK now I see your point, the CAI might be choked back by stock exhaust enough that dyno measurement did not look like much of anything. Makes sense.

And I'll add one other thing, ideally the full set of measurements you're talking about would be done on same vehicle and dyno, by same operator. From the looks of it that is not going to happen. We will probably get some idea of all stock vs the 3 piece system however, which is better than nothing
11-27-2011 11:04 AM
scooby2003 I'm good just I kinda crushed my y pipe and put a dent in my cross member
11-27-2011 11:02 AM
bo9roadking
Quote:
Originally Posted by scooby2003 View Post
What did you do with the stock y pipe ? I had an offroad accident ::hides::
It is in my garage with the rest of my exhaust. I'm not sure if I'm going to keep it or sell it. Sorry to hear that you were in an accident. I hope you are ok.
11-27-2011 10:56 AM
scooby2003
Quote:
Originally Posted by bo9roadking
Yes, in addition to the y-pipe, I bought a Coast 1310 front driveshaft. Depending on the size of your lift, you could get by with one or the other. I had to get both. The stock front driveshaft angle was too steep at the transfer case and was pinching the boot. It would have failed pretty fast. After I replaced the driveshaft with the aftermarket one, I had to get the y-pipe because even with the smaller diameter of the aftermarket driveshaft, I had about 1/4" of clearance before the driveshaft would hit the stock exhaust. I didn't want to take any chances while offroading that my driveshaft was going to hit the exhaust. I may do a long arm lift in the future which will also improve my Jeeps droop and that would have definitely hit the exhaust if I didn't use the y-pipe to move it out of the way.
What did you do with the stock y pipe ? I had an offroad accident ::hides::
11-27-2011 10:29 AM
bo9roadking
Quote:
Originally Posted by FOUR FLUSHER View Post
Did you do new DS's and the AFE y tube? I'm ready go down that road
Yes, in addition to the y-pipe, I bought a Coast 1310 front driveshaft.

The stock front driveshaft angle was too steep at the transfer case and was pinching the CV boot. It would have failed pretty fast. The stock driveshaft was also hitting on the crossover exhaust, so replacing the driveshaft was necessary. After I replaced the driveshaft with the aftermarket one, I had about 1/4" of clearance before the driveshaft would hit the stock exhaust. I didn't want to take any chances while offroading that my driveshaft would hit the exhaust, so I relocated it with the aFe y-pipe. I may do a long arm lift in the future which will also improve my Jeeps droop and that would have definitely hit the exhaust if I didn't use the y-pipe to move it out of the way.
11-27-2011 10:24 AM
bo9roadking
Quote:
Originally Posted by sonofboxster View Post
There's a decent torque bump at 2500 rpm, but it is unfortunately followed by a sag to 4000. Wonder if that sag is there in stock form, it is certainly there with y-pipe, cat back and stock intake.

Hummm, need to see the stock curves.
I agree with you about the nice tq bump and wanting to see the stock curves. However, the published numbers which reflect the largest improvement are at almost 5000 rpm where the power band has already started dropping on the downward "sag" of the curve and most Jeep owners aren't running in that rpm range. Since the dyno chart is not marked in smaller increments, it is hard to know exactly how much useable hp/tq is in the bump at 2500 rpm. Guessing, I'd say the number is in single digits.
11-27-2011 10:17 AM
bo9roadking
Quote:
Originally Posted by sonofboxster View Post
The test should reflect only the improvement due to the intake since y-pie and cat back were on for both tests, no? Or did I misunderstand your point.

I would love to see the total of all three against stock, along with the breakout of which piece contribute what percent of the total. Don't know if aFe will go to the trouble, but it would be nice!

I'm set on a cat back regardless, I've got the hear the engine singing

aFe looks to be best of bunch from what I've seen so far.
I like aFe's products and I am glad that they are ahead of the game getting products out for the 2012 Jeeps.

The point that I was trying to make is that if someone wanted to buy the CAI, they don't know if they will actually see that hp/tq improvement because they might be running the stock exhaust. The way aFe has written the CAI description on their webpage, it appears that those numbers are available just from installing the CAI, but the published test results didn't use the stock exhaust. In order to get those numbers, you need to buy the CAI and the exhaust according to their dyno sheet. For the test to be of any benefit, there should have been at least 4 published sets of numbers.

The first dyno run should have the stock set of numbers to establish a baseline for all of the other tests. We know what Chrysler says the hp/tq numbers are for the engine, but I haven't seen what those numbers are at the wheels. The second dyno run should have only included the CAI to see what improvements it brings. The third test should have been only the exhaust/y-pipe. The final test would be what aFe has done, which is testing their entire setup. Of course you could have additional tests with different configurations, but I think those should have been the major ones.

By only publishing the test using their exhaust/y-pipe with and without their CAI, we don't know if the CAI provided the 12hp/13tq numbers or if the exhaust has also helped. It looks on the surface that the CAI provided all of the benefit, but why didn't aFe publish the CAI with the stock exhaust. I'm betting that those numbers were negligible because the stock intake and exhaust were too restrictive. If that is the case, the only way to see a real improvement is to replace both the intake and the exhaust because replacing only one adds no measurable difference.
11-26-2011 08:28 AM
FOUR FLUSHER Did you do new DS's and the AFE y tube? I'm ready go down that road
11-26-2011 08:10 AM
sonofboxster
Quote:
Originally Posted by bo9roadking View Post
The main problem is that most of the increase is not in the normal working range of the Jeep. The dyno chart shows an increase across the whole rpm range which is good, but the published numbers of 12 hp and 13 tq are the max numbers at 4960 rpm.
There's a decent torque bump at 2500 rpm, but it is unfortunately followed by a sag to 4000. Wonder if that sag is there in stock form, it is certainly there with y-pipe, cat back and stock intake.

Hummm, need to see the stock curves.
11-26-2011 07:58 AM
sonofboxster
Quote:
Originally Posted by bo9roadking View Post
I was hoping the numbers would have been better, but it is an increase that is worth considering. I wonder how much of the increase was the exhaust and how much was the CAI. I may be getting some of that improvement already with the exhaust and y-pipe installed. I'm still considering the CAI.

The main problem is that most of the increase is not in the normal working range of the Jeep. The dyno chart shows an increase across the whole rpm range which is good, but the published numbers of 12 hp and 13 tq are the max numbers at 4960 rpm.
The test should reflect only the improvement due to the intake since y-pie and cat back were on for both tests, no? Or did I misunderstand your point.

I would love to see the total of all three against stock, along with the breakout of which piece contribute what percent of the total. Don't know if aFe will go to the trouble, but it would be nice!

I'm set on a cat back regardless, I've got the hear the engine singing

aFe looks to be best of bunch from what I've seen so far.
11-25-2011 06:59 AM
bo9roadking After thinking about the aFe hp/tq numbers a bit more and why aFe might have chosen to use their exhaust for both tests, I've concluded that maybe the stock exhaust was so restrictive that it had to be replaced to get some decent numbers. With that being said, does anyone know what the stock hp/tq numbers are at the wheel? Maybe aFe's numbers are even better when compared to the stock numbers that don't take into account the aFe exhaust.
11-24-2011 03:52 PM
bo9roadking
Quote:
Originally Posted by sonofboxster View Post
aFe posted a dyno comparing only their intake against stock, both tests had y-pipe and cat back - under product details

Cold Air Intake System Stage 2 aFe Power Magnum FORCE Stage 2* Air Intake System; Pro 5R; Jeep Wrangler 2012 V6-3.6L 54-12092 - aFe Power
I was hoping the numbers would have been better, but it is an increase that is worth considering. I wonder how much of the increase was the exhaust and how much was the CAI. I may be getting some of that improvement already with the exhaust and y-pipe installed. I'm still considering the CAI.

The main problem is that most of the increase is not in the normal working range of the Jeep. The dyno chart shows an increase across the whole rpm range which is good, but the published numbers of 12 hp and 13 tq are the max numbers at 4960 rpm.
11-23-2011 06:15 PM
sonofboxster aFe posted a dyno comparing only their intake against stock, both tests had y-pipe and cat back - under product details

Cold Air Intake System Stage 2 aFe Power Magnum FORCE Stage 2* Air Intake System; Pro 5R; Jeep Wrangler 2012 V6-3.6L 54-12092 - aFe Power
11-22-2011 11:25 AM
bo9roadking
Quote:
Originally Posted by sonofboxster View Post
Thanks, I'll have a look. I emailed the company who said they will have Dyno results for the 3.6 L posted this week. looking forward to that.
Thanks for the update. I know that they said dyno results would be posted, but I didn't know when. I'll have to keep checking back with their site this week to get the results.
11-22-2011 11:11 AM
sonofboxster
Quote:
Originally Posted by bo9roadking View Post
I have posted about the y-pipe in my build thread that can be found here:
http://www.wranglerforum.com/f33/201...od-117887.html

In that thread, I specifically talk about the y-pipe performance here:
http://www.wranglerforum.com/f33/201...ml#post1664972
Thanks, I'll have a look. I emailed the company who said they will have Dyno results for the 3.6 L posted this week. looking forward to that.
11-22-2011 09:18 AM
bo9roadking
Quote:
Originally Posted by sonofboxster View Post
Good thread, interested in cat back myself, Sport S on order

Any noticeable performance or sound increase just from y-pipe?
I have posted about the y-pipe in my build thread that can be found here:
http://www.wranglerforum.com/f33/201...od-117887.html

In that thread, I specifically talk about the y-pipe performance here:
http://www.wranglerforum.com/f33/201...ml#post1664972
11-22-2011 08:13 AM
sonofboxster
Quote:
Originally Posted by bo9roadking View Post
I already had the aFe y-pipe installed
Good thread, interested in cat back myself, Sport S on order

Any noticeable performance or sound increase just from y-pipe?
11-22-2011 07:13 AM
DonC72 Looks good. Please keep us posted after a week or so! You are lucky to have access to the tools and a bay lift! This is one I'd be forced to pay on!
11-22-2011 07:03 AM
Silverton34 Hmmmm, 50+ ft/lbs of torque increase is significant, if it's real. Anybody try this in the real world?
11-22-2011 06:21 AM
bo9roadking
Quote:
Originally Posted by lbrito View Post
Looking good. What does the butt dyno say? any perceived increases in performance?
I drove it to work this morning and spent about 15 miles on the hwy and a few more miles in town. Acceleration seems to be a bit faster, but I don't know if it is because the exhaust note makes the Jeep "sound" more powerful or if I'm actually feeling a little bit more power. In either case, it is still fun to hear the exhaust. I found that I don't hear the exhaust on the hwy running at steady speeds because the road noise and radio drown out the exhaust. If I hit the gas to pass someone, then I hear the exhaust again.

I'm still waiting for aFe to publish hp/tq numbers on their website to see if the perceived power is an actual improvement or my imagination. If there is an increase, I'll be investigating the purchase of a CAI to possibly get additional power improvements. I'd look at the aFe CAI first, since I already have their y-pipe and cat-back. If I do purchase one, I want to make sure that it does a good job of filtering so that I don't get extra debri in the engine. I noticed that aFe has a couple of different filters and a pre-filter, but other companies probably do also.

If you watch aFe's youtube video,
http://www.youtube.com/watch?v=YuyZGlWQedo at about 4 minutes and 32 seconds into it, you can hear the exhaust. I know that the video is using a 3.8 and I have a 3.6, but the sound is very similar.
11-22-2011 01:09 AM
LBrito Looking good. What does the butt dyno say? any perceived increases in performance?
11-21-2011 07:17 PM
bo9roadking
aFe Cat-Back Exhaust Installed

I finally got my exhaust upgraded. The model that I have is the aFe Power MACH Force XP Hi-Tuck Cat-Back Exhaust System that is 2.5" in diameter and made from 409 stainless steel. The fit and finish is very well done and the install was straight forward. I already had the aFe y-pipe installed, so now it was time to get the rest of my exhaust upgraded. I had the stock exhaust pipe and muffler removed from the y-pipe connection and then installed the 2 sections of aFe exhaust pipe and the Hi-Tuck muffler using the stock hanger locations. There were 3 clamps to tighten to finish the install. The entire job took about 40 minutes.

I've only driven about 20 miles with the new exhaust, but I'm liking it. It is still early to tell if there are any performance or mpg improvements. I can definitely hear the exhaust now when accelerating, so if there is an mpg improvement, I probably won't notice because I'll be pushing on the gas to hear more of the exhaust sound. It has a mellow, but throaty sound below 2000 rpm and then starts to sound more like a 350z sports car at the higher rpms. I expected this because it isn't exactly a V8 under the hood. At highway cruising speed, I don't notice the exhaust sound, but I can hear it if I push on the gas pedal to adjust speeds.

The Hi-Tuck muffler is a lot smaller than the stock muffler and it tucks up between the frame rails for protection in the stock muffler location. It is protected so well that I don't see the muffler when I'm standing at the rear of the Jeep. I was concerned with my stock muffler getting dented up, so I was considering a muffler skid. I don't need one now because the aFe muffler is almost invisible.

I took some photos, so I'll post them to give you a better idea of what it looks like.

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