CE y-pipe: Is it slower with it?
12-14-2006, 02:52 PM
#1
CE y-pipe: Is it slower with it?
So I put the y-pipe on with the motor mounts and I got to say I think the car might be slower. It's hard to say, at times it seems a little fast, at times a little slower. Also it seems to rev slower, is that even possible swapping an exhaust. I'm so confused. A freer flowing exhaust should help make more power. I am aware I need to tune to get full potential, but freeing up the exhaust should net some gains without a tune.
Thoughts?
Thoughts?
12-14-2006, 03:54 PM
#3
But a factory exhaust that pinches the tubes will hurt EVERYWHERE. Smaller is not better and people can debate what they will, but a larger exhaust will always net more power as long as it doesn't completely kill velocity.
Off point, it seems slower on the bottom, mid, and top; plus the revving issue.
I would like to hear only from people who have run this mod prior or are currently using it.
No offense to anyone, but I want to hear from experience, not theory.
Off point, it seems slower on the bottom, mid, and top; plus the revving issue.
I would like to hear only from people who have run this mod prior or are currently using it.
No offense to anyone, but I want to hear from experience, not theory.
12-14-2006, 04:14 PM
#4
i have a cattman y on my 02. our exhausts are very similar. i dynoed 218WHP/228TQ with the y and a short ram. its worth maybe 5-10WHP. headers is the way to go, i got my HS ones going on soon. the older maximas had the cats in the y and gained lots of power. for your car and mine, the precats are in the manifolds, thats why headers give so much power
12-14-2006, 08:23 PM
#8
Originally Posted by Nietzsche
I would like to hear only from people who have run this mod prior or are currently using it.
No offense to anyone, but I want to hear from experience, not theory.
No offense to anyone, but I want to hear from experience, not theory.
lololol 
12-14-2006, 10:03 PM
#9
Did you flash your ECU? IF you did not modify your ECU or add a APEXi computer then your cars computer will actually modify it's output to negate most of the aftermarket goodies. I manually reflash the computer by using the pedal/floor technique. I am so praticed at this that I can do it in under 2 mins and voila lots of power. I also put in 94 Octane in the summer, so with all of that man does it unleash the beast! In the summer I do this about every 300 miles and/or every 2 fillups. Or on a sunny summer day when I feel like Mario Andretti LOL! There are guys here that are getting 250 HP at the wheel! I once shamed a 1998 Camaro SS on the Highway that was trying to pass me! Ha ha you should of seen the look on his face as I shifted from 3rd to 4th on the Auto tranny using the technique of holding down the shifter in manual mode. This keeps the tranny from shifting early in to 4th alowing you to redline in to 4th by using your lock up torque converter. But you need to know your engine sound and precise shift point or the failsafe will kick in. Some Max's here redline at 110 mph in 3rd gear! I don't advocate racing especially in the street. I don't like it on the highway either although an open stretch of emtpy highway is nice though.
Safe and Happy motoring!
Safe and Happy motoring!
12-15-2006, 12:01 AM
#10
Newbie just Registered
Join Date: May 2005
Location: LA/OC, CA
Posts: 2,795
What other mods you have? With y-pipe, you do lose some back pressure which decrease some initial torque, but give you more power up top. Same with CAI and exhaust. If you have all 3 then you'd really notice the lowend loss.
12-15-2006, 06:23 AM
#11
Originally Posted by RHMax
If you have all 3 then you'd really notice the lowend loss.
12-15-2006, 11:03 AM
#12
Originally Posted by xoomer.com
Makes me triple think if I want to do it now. I already have CAI which definitelly takes away from low end and picks up like a monster once the RPM is high'er. If I add the Y-pipe and catmann exhaust and it takes away the low end...than I might as well skip it.
The key to all the mods is the ECU. If u lean out your mixture by adding go-fast gadgets (CAI, Y-pipe, Exhaust) you need to have the ECU tuned to dump more gas at early throttle tip in.
I'm pretty positive Deus has the fastest N/A no bottle 6th gen here. When he gets his headers..... good bye.
Kamski
12-15-2006, 11:12 AM
#14
Originally Posted by xoomer.com
what would be required to "upgrade" the ECU. Is it safe?
Its safe and they can allways reverse it.
BOOM TEK got 19hp and Deus..... im not even sure what he got but whatver it was it was FAST.
Kam
12-15-2006, 01:43 PM
#15
I know the bottom end loses a bit, but even the top end feels softer. Reseting the ECU doesn't do much in the long run plus I have the timing advanced and am not sure if it would revert to the standard timing. Anyone know if clearing the ECU switches your timing back to normal? Once I get a datalogger I will be monitering my ratios and getting a flash done.
12-16-2006, 06:50 PM
#16
I would recommend that you get a UDP. This will free up bottom end big time.
Also a pop charger like a Fujita in stead of a CAI like an AEM would improve that also. I prefer having the passing power on the highway so all this is good. My spring goodies will include a Y-pipe, Greddy Cat Back and installation of my APEXi NEO which I already have in the closet.
Also a pop charger like a Fujita in stead of a CAI like an AEM would improve that also. I prefer having the passing power on the highway so all this is good. My spring goodies will include a Y-pipe, Greddy Cat Back and installation of my APEXi NEO which I already have in the closet.
12-16-2006, 10:01 PM
#18
A few weeks ago I got the CE Y-Pipe and a spare ECU flashed by Technosquare. Hours after, the SES light came on. Like I posted on other threads, I found my A/F going real lean (18:1). CAI, headers and mods that improve air flow will lean out the A/F and make you loose mid-range power during WOT. After a few weeks working with my Autoginuity software I got the A/F between 12.3:1 and 13.7:1. I modified the MAF sensor to increase the air flow to force the ECU to run richer. I had to increase the MAF airflow by 30%+ to get stoic again. I don’t recommend this approach unless you have this software, Cipher or other datalogging tool.
You can send the ECU back to Techno after every mod but that's $150 a pop. The correct way IMO is to get a piggyback controller like Apexi Neo, AEM fic, Greddy E-manage, HKS, etc. This will allow you to fine tune the A/F ratio across the RPM range.
I did notice the Y-pipe power variation before I fixed the A/F. The reason I found: 1) under closed loop (partial throttle), the ECU will adjust the ‘trims’ and attempt to stay stoic using the O2 signal (but was still a bit lean on my car). 2) At WOT or under heavy throttle, the ECU goes to open loop. In that mode, the ECU stops using the O2 data and primarily uses its fuel map and MAF data. The impact for me was a real lean condition with A/F between 16:1 and 18:1. I did not believe my software and went for a dyno run. Got 18:1 between 2.5-5K rpm, down to 14.9:1 @ 5700, and back to 18:1 at 6400. An A/F of 18:1 is not real safe. Engine ran well when cold/cool, but sluggish when very hot.
The reason my SES light came on with code P0171, P0174 was the combo of the CAI and Y-pipe sending the A/F lean beyond what the ECU could adjust. Now with a better fuel ratio, the timing has backed off almost 5 degrees (no more pigging), the engine runs cooler, and power is up about 5-6%.
You could try cleaning your MAF sensor with CRC MAF Cleaner. It did improve my sensor reading (according to software) but I did not feel a difference. Ask for a piggyback controller for Xmas.
You can send the ECU back to Techno after every mod but that's $150 a pop. The correct way IMO is to get a piggyback controller like Apexi Neo, AEM fic, Greddy E-manage, HKS, etc. This will allow you to fine tune the A/F ratio across the RPM range.
I did notice the Y-pipe power variation before I fixed the A/F. The reason I found: 1) under closed loop (partial throttle), the ECU will adjust the ‘trims’ and attempt to stay stoic using the O2 signal (but was still a bit lean on my car). 2) At WOT or under heavy throttle, the ECU goes to open loop. In that mode, the ECU stops using the O2 data and primarily uses its fuel map and MAF data. The impact for me was a real lean condition with A/F between 16:1 and 18:1. I did not believe my software and went for a dyno run. Got 18:1 between 2.5-5K rpm, down to 14.9:1 @ 5700, and back to 18:1 at 6400. An A/F of 18:1 is not real safe. Engine ran well when cold/cool, but sluggish when very hot.
The reason my SES light came on with code P0171, P0174 was the combo of the CAI and Y-pipe sending the A/F lean beyond what the ECU could adjust. Now with a better fuel ratio, the timing has backed off almost 5 degrees (no more pigging), the engine runs cooler, and power is up about 5-6%.
You could try cleaning your MAF sensor with CRC MAF Cleaner. It did improve my sensor reading (according to software) but I did not feel a difference. Ask for a piggyback controller for Xmas.
12-17-2006, 12:54 AM
#19
I'm glad auto enginuity worked so well for you. I was debatting whether it would work as well as cipher for datalogging. How does the AFR work out? Did you have to convert it yourself or does the program do it for you? Also, how did you adjust the MAF with Auto Enginuity; or do you have a air/fuel controller?
Thanks for the help guys!
Thanks for the help guys!
12-17-2006, 09:12 AM
#20
Yes I have to convert output voltages manually. In service manual EC, page 520, there is a voltage/AFR chart similar to a wideband sensor but not quite as linear. For the narrowband sensor voltage I found a chart on the net.
The way I changed the MAF air flow is by drilling holes in the back of the sensor, not in the 3 inch CAI pipe, but the sensor inside the pipe.
http://memimage.cardomain.net/member...2248073_25.jpg
The air enters the MAF sensor and makes a 'U' turn inside and then exits from the top and bottom of the sensor. I created a shortcut by enlarging one hole on the top of the sensor and created three 1/16 inch holes in the back. Took about 7 tries. If you don't have a tool to monitor the AFR, you can go too rich quickly. To remove the sensor you need the Torx bit with the hole in the center (Advance Auto $10.00 for a set). Pliers make a mess. I have also positioned the sensor at 1 o'clock in the pipe so it can be pulled out easily. I suspect that with patience one could use more or less holes to improve just the low or high-end range. I don't have an A/F controller yet.
I will take a better picture of the sensor with the holes in the back.
The way I changed the MAF air flow is by drilling holes in the back of the sensor, not in the 3 inch CAI pipe, but the sensor inside the pipe.
http://memimage.cardomain.net/member...2248073_25.jpg
The air enters the MAF sensor and makes a 'U' turn inside and then exits from the top and bottom of the sensor. I created a shortcut by enlarging one hole on the top of the sensor and created three 1/16 inch holes in the back. Took about 7 tries. If you don't have a tool to monitor the AFR, you can go too rich quickly. To remove the sensor you need the Torx bit with the hole in the center (Advance Auto $10.00 for a set). Pliers make a mess. I have also positioned the sensor at 1 o'clock in the pipe so it can be pulled out easily. I suspect that with patience one could use more or less holes to improve just the low or high-end range. I don't have an A/F controller yet.
I will take a better picture of the sensor with the holes in the back.
12-17-2006, 07:51 PM
#22
12-18-2006, 08:21 PM
#24
Bad in what sense? I have richer, safer AFR. I have not noticed any adverse effect yet: starts fine at 25F up to 65F. No stalling or unusual behavior. If I ever go back to stock, I will just plug the holes.
I like to experiment. Sometimes I break stuff. In this case it seems to have fixed my problem.
Get your car on a dyno. Its a quick way to find out if your AFR is correct.
I like to experiment. Sometimes I break stuff. In this case it seems to have fixed my problem.
Get your car on a dyno. Its a quick way to find out if your AFR is correct.
12-21-2006, 05:42 PM
#26
Originally Posted by madmik
I did notice the Y-pipe power variation before I fixed the A/F. The reason I found: 1) under closed loop (partial throttle), the ECU will adjust the ‘trims’ and attempt to stay stoic using the O2 signal (but was still a bit lean on my car). 2) At WOT or under heavy throttle, the ECU goes to open loop. In that mode, the ECU stops using the O2 data and primarily uses its fuel map and MAF data. The impact for me was a real lean condition with A/F between 16:1 and 18:1. I did not believe my software and went for a dyno run. Got 18:1 between 2.5-5K rpm, down to 14.9:1 @ 5700, and back to 18:1 at 6400. An A/F of 18:1 is not real safe. Engine ran well when cold/cool, but sluggish when very hot.
12-22-2006, 08:42 AM
#29
Originally Posted by NmexMAX
It still wont give you true a/f like a wideband o2 sensor would. Only o2 sensor data.
Happy holidays.
12-22-2006, 11:20 AM
#30
Originally Posted by NmexMAX
It still wont give you true a/f like a wideband o2 sensor would. Only o2 sensor data.
If I'm mistaken in any way please enlighten me.
12-23-2006, 12:56 AM
#31
Originally Posted by Nietzsche
What's the difference. If you have the raw voltage converting it is just an equation. If you buy a wideband o2 it does the same conversion does it not. The Maxima uses wideband o2's so how are they any different then a aftermarket system? I was planning on using AE or Cipher as my o2 datalogger instead of going through the hassle of installing another o2 sensor.
If I'm mistaken in any way please enlighten me.
If I'm mistaken in any way please enlighten me.
Originally Posted by madmik
Correct. Like I mentioned earlier: I have to convert output voltages manually. In the service manual EC, page 520, there is a chart to convert voltage to A/F. I will dyno again in January. My a/f roughly follows my torque chttp://forums.maxima.org/newreply.php?do=newreply&p=5427115urve: about 12.1-12.2 @5500, and 13.1-13.5 for the rest of the range between 3500-6500. I will dyno again in January. I hope it shows similar numbers.
Happy holidays.
Happy holidays.
But keep in mind, the 05(madmik) and yours(06+), are different...(o2 sensors).
12-23-2006, 04:35 PM
#32
Originally Posted by NmexMAX
This man (madmik) is always right/correct. And...again, Happy Holidays....
But keep in mind, the 05(madmik) and yours(06+), are different...(o2 sensors).
But keep in mind, the 05(madmik) and yours(06+), are different...(o2 sensors).
Thanks for letting me know though, things might have gotten ugly.
12-27-2006, 02:26 AM
#36
Newbie - Just Registered
Join Date: Aug 2006
Posts: 14
Guys, can you FLASH your ECU to get some gains without any real mods other than exhaust & a K&N filter or is that just a waste of time? cause i saw in a thread here once the directions to flash the ecu using the pedal/flash method when i tried that it didnt work. do you need a flash system like the apexi one or something..the thread made it seem like any max owner could do the pedal method...also..the max's throttle response seemed crazy after i installed the k&N filter.....for like 2 days. =( (HELP) and sry for such a stupid question guys.
12-27-2006, 08:01 AM
#37
Originally Posted by bmorekaotic19
Guys, can you FLASH your ECU to get some gains without any real mods other than exhaust & a K&N filter or is that just a waste of time? cause i saw in a thread here once the directions to flash the ecu using the pedal/flash method
Read this, http://forums.maxima.org/showpost.ph...3&postcount=22
12-27-2006, 10:06 AM
#38
Originally Posted by NmexMAX
Ok........what years are those?
12-27-2006, 01:05 PM
#39
Supporting Maxima.org Member
Join Date: Oct 2005
Location: Brooklyn NY
Posts: 620
i will tell you first hand that i had a ce-y pipe and then took it off a few months later. The reason i took it off because i added a full exhuast, once i added that the car felt like a complete pig. Didnt even burn tires off the light. All these exhuast mods cause the car to lose back pressure and in the end you lose your low end power. The y pipe did make my car feel slightly quicker on top end but not to much, but i definatly felt the lack of power on the bottom before and after teh exhuast.
I also never got a tune which definatly would have helped everything work well together.
I also never got a tune which definatly would have helped everything work well together.
12-27-2006, 02:21 PM
#40
Originally Posted by logik05se
i will tell you first hand that i had a ce-y pipe and then took it off a few months later. The reason i took it off because i added a full exhuast, once i added that the car felt like a complete pig. Didnt even burn tires off the light. All these exhuast mods cause the car to lose back pressure and in the end you lose your low end power. The y pipe did make my car feel slightly quicker on top end but not to much, but i definatly felt the lack of power on the bottom before and after teh exhuast.
I also never got a tune which definatly would have helped everything work well together.
I also never got a tune which definatly would have helped everything work well together.
My car never lost any 'low end' due to loss of backpressure.