DC Sports Header install and evaluation - Page 5 - Toyota Yaris Forums

Galavoxx · 08-17-2009, 02:39 PM

Quote:

Originally Posted by NonStopTuning

Very nice review Galavoxx!

Shameless plug coming next...
perhaps you should try an Underdrive Crank Pulley to help you regain some of that low end torque. Should be very helpful for hill climbing!

Good luck and have fun with all your projects!

LOL. Is the underdrive really going to help that much? I already have your lightened crank pulley. Plus, I'm saving for a rainy custom intake day.

Galavoxx · 08-17-2009, 02:40 PM

Anyone have any comments on the ECU question?

cali yaris · 08-17-2009, 02:58 PM

Well, you have changed the amount of air (and fuel) passing through the motor. So your ECU will definitely "notice" that and be making some adjustments (= "relearn"). I'm not sure you have to reset it for it to do that, but it's not a bad idea.

eii · 08-17-2009, 03:11 PM

Quote:

Originally Posted by lilredrocket

I may be thinking wrong but any time you perform a mod that is supposed to increase power you are supposed to disconnect the battery to reset the ECU? Like I said I'm not 100% sure about that

You should. When I installed the headers for the first time I didnt d/c the battery and I got CEL after a few minutes driving. Reset the battery and you shouldn't get a CEL ever assuming installation was done correctly. Running some crap ebay headers with no problems for a month now. :)

Galavoxx · 08-17-2009, 03:27 PM

I didn't throw a CEL but I'll disconnect overnight and see how it feels afterward.

lilredrocket · 08-17-2009, 07:52 PM

You may want to rev it up acouple time after you start it back up to help the ECU out a little.

DerFlosser · 08-17-2009, 08:05 PM

Fantastic write-up! I will definitely hold off on this mod. Thanks again for the great post.

Galavoxx · 08-17-2009, 08:06 PM

Hmmm... I read about that trick. I'm a little skeptical but I'll definitely go on a drive afterward, give it some juice.

fmicle · 08-18-2009, 12:38 PM

Can someone please explain the physics of why would you lose some low-end torque with a less restrictive header? It's not quite intuitive to me, as to why that would happen, but I admit I'm not a mechanic

It's too late for me anyway, as I ordered mine last week

but I'd still like to understand what happens there.

Galavoxx · 08-18-2009, 04:15 PM

I don't know the physics behind it but I'm assuming it has to do the scavenging properties of the new header. The header doesn't take the exhaust gasses away fast enough at low RPMS due to an increased volume in tubing. The pressure in the manifold is probably too low. Once the engine begins to rev higher and the exhaust pressure begins to rise, that additional volume gets put to use and allows for the exhaust gasses to be expelled more quickly and freely than that stock header that was on there. I could be completely wrong but that's my experience with two-stroke motorcycle stuff talking. I imagine the principles are the same.

DerFlosser · 08-18-2009, 08:09 PM

slimmer tube....faster flow and the interior geometry and surface finish also matters. A fatter tube with such a weak motor and you will feel the loss in torque due to less velocity. Don't forget, the car was designed/engineered as a whole unit which means that the overall efficiency is probably maximized with the stock exhaust header. Add some other modifications and well....that story might not hold truth any longer.

Herbicidal · 08-20-2009, 09:41 PM

Quote:

Originally Posted by Galavoxx

...I tried to drive the car as much as possible this weekend but was pretty busy. Based on about an hour of driving, maybe a little more, I have to agree with others that I have definitely lost some low end torque. The car does not want to climb hills below 3000 rpms in second gear, which I used to be able to do. I'm in San Francisco so this matters. There are many hills...

...If you simply must have a header I would hit up one of the cheaper options. I'm glad I bought this header because I wanted a header and like a quality product and this is definitely both. I wasn't expecting huge gains so I'm not disappointed. I think I will miss that little bit of low end torque though...

Galavoxx - Based upon your write up, particulary regarding your comments above, I changed my order with Garm from the DC to the Megan. The Megan header arrived yesterday and looks good to me (thanks Garm!). We'll see if I made the right decision. I did save some coin by switching and perhaps I'll use the difference to buy a higher flowing air filter. I hope to find an hour or two this weekend to do the install. I think I will pick up some of that Permatex Ultra Copper first.

Galavoxx · 08-21-2009, 11:01 PM

I disconnected the battery for a couple of hours today and went for a heavy footed drive up and down highway 280 and then up and down some hills.

At first it seemed like nothing was different. This is probably because I was skeptical the ECU would change anything given I had already driven the car for 100 miles or so.

Well, I was totally wrong. The low end torque feels like it's back! I did some "tests" up some of the steeper hills in my neighborhood and I can definitely feel more power down low. I don't know the exact extent of the change when compared to the stock header but the throttle response really is better and the engine just feels like it has better pull than before the ECU reset. I can say that disconnecting the ECU definitely helped things and anyone adding a header should probably perform the reset. I'm going to go on an early drive up highway 1 to Tamales Bay tomorrow morning, grab some breakfast and see if it gets even better!! Thank you all for the suggestion.

Galavoxx · 08-21-2009, 11:03 PM

Quote:

Originally Posted by Herbicidal

Galavoxx - Based upon your write up, particulary regarding your comments above, I changed my order with Garm from the DC to the Megan. The Megan header arrived yesterday and looks good to me (thanks Garm!). We'll see if I made the right decision. I did save some coin by switching and perhaps I'll use the difference to buy a higher flowing air filter. I hope to find an hour or two this weekend to do the install. I think I will pick up some of that Permatex Ultra Copper first.

Hey Herb (haha)... I'm curious to know if your low end suffers at all. After the ECU reset mine feels like is probably back to where it was at stock. Let us know what you think after you've installed.

Herbicidal · 08-21-2009, 11:36 PM

Quote:

Originally Posted by Galavoxx

Hey Herb (haha)... I'm curious to know if your low end suffers at all. After the ECU reset mine feels like is probably back to where it was at stock. Let us know what you think after you've installed.

Will do! Enjoy your drive up hwy 1!

lilredrocket · 08-21-2009, 11:56 PM

Glad to hear that helped

rac23 · 08-22-2009, 06:08 PM

Galavoxx
Great to hear. I hope it gets even better for you tomorrow.

fmicle · 08-22-2009, 09:22 PM

Quote:

Originally Posted by Galavoxx

...
Well, I was totally wrong. The low end torque feels like it's back!
...

whew, good, 'cause I've already ordered mine

08-17-2009, 02:58 PM	#75
cali yaris ULTIMATE View User's Garage Drives: 07 Yaris Turbo Join Date: May 2007 Location: Canoga Park, CA Posts: 14,859	Well, you have changed the amount of air (and fuel) passing through the motor. So your ECU will definitely "notice" that and be making some adjustments (= "relearn"). I'm not sure you have to reset it for it to do that, but it's not a bad idea. __________________ Micro Image forums, online store and shop are now closed. It was a great eight year run, but it was time to focus on other things. I'm still selling parts on eBay under micro*image seller ID and customers can still make requests for anything specific.

08-17-2009, 07:52 PM	#78
lilredrocket Slowy getting there View User's Garage Drives: 08 Liftback Join Date: Nov 2008 Location: DFW, Texas Posts: 1,464	You may want to rev it up acouple time after you start it back up to help the ECU out a little. __________________

08-21-2009, 11:56 PM	#88
lilredrocket Slowy getting there View User's Garage Drives: 08 Liftback Join Date: Nov 2008 Location: DFW, Texas Posts: 1,464	Glad to hear that helped __________________

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08-17-2009, 02:40 PM	#74
Galavoxx View User's Garage Drives: Yaris Hatch Join Date: Oct 2006 Location: San Francisco Posts: 397	Anyone have any comments on the ECU question?

08-17-2009, 03:27 PM	#77
Galavoxx View User's Garage Drives: Yaris Hatch Join Date: Oct 2006 Location: San Francisco Posts: 397	I didn't throw a CEL but I'll disconnect overnight and see how it feels afterward.

08-17-2009, 08:05 PM	#79
DerFlosser Drives: Yaris Join Date: Apr 2009 Location: USA Posts: 355	Fantastic write-up! I will definitely hold off on this mod. Thanks again for the great post.

08-17-2009, 08:06 PM	#80
Galavoxx View User's Garage Drives: Yaris Hatch Join Date: Oct 2006 Location: San Francisco Posts: 397	Hmmm... I read about that trick. I'm a little skeptical but I'll definitely go on a drive afterward, give it some juice.

08-18-2009, 12:38 PM	#81
fmicle Drives: 2007 Yaris LB Join Date: Mar 2007 Location: San Jose, CA, USA Posts: 685	Can someone please explain the physics of why would you lose some low-end torque with a less restrictive header? It's not quite intuitive to me, as to why that would happen, but I admit I'm not a mechanic It's too late for me anyway, as I ordered mine last week but I'd still like to understand what happens there.

08-18-2009, 04:15 PM	#82
Galavoxx View User's Garage Drives: Yaris Hatch Join Date: Oct 2006 Location: San Francisco Posts: 397	I don't know the physics behind it but I'm assuming it has to do the scavenging properties of the new header. The header doesn't take the exhaust gasses away fast enough at low RPMS due to an increased volume in tubing. The pressure in the manifold is probably too low. Once the engine begins to rev higher and the exhaust pressure begins to rise, that additional volume gets put to use and allows for the exhaust gasses to be expelled more quickly and freely than that stock header that was on there. I could be completely wrong but that's my experience with two-stroke motorcycle stuff talking. I imagine the principles are the same.

08-18-2009, 08:09 PM	#83
DerFlosser Drives: Yaris Join Date: Apr 2009 Location: USA Posts: 355	slimmer tube....faster flow and the interior geometry and surface finish also matters. A fatter tube with such a weak motor and you will feel the loss in torque due to less velocity. Don't forget, the car was designed/engineered as a whole unit which means that the overall efficiency is probably maximized with the stock exhaust header. Add some other modifications and well....that story might not hold truth any longer.

08-21-2009, 11:01 PM	#85
Galavoxx View User's Garage Drives: Yaris Hatch Join Date: Oct 2006 Location: San Francisco Posts: 397	I disconnected the battery for a couple of hours today and went for a heavy footed drive up and down highway 280 and then up and down some hills. At first it seemed like nothing was different. This is probably because I was skeptical the ECU would change anything given I had already driven the car for 100 miles or so. Well, I was totally wrong. The low end torque feels like it's back! I did some "tests" up some of the steeper hills in my neighborhood and I can definitely feel more power down low. I don't know the exact extent of the change when compared to the stock header but the throttle response really is better and the engine just feels like it has better pull than before the ECU reset. I can say that disconnecting the ECU definitely helped things and anyone adding a header should probably perform the reset. I'm going to go on an early drive up highway 1 to Tamales Bay tomorrow morning, grab some breakfast and see if it gets even better!! Thank you all for the suggestion.

08-22-2009, 06:08 PM	#89
rac23 Drives: 2007 Yaris Hatchback Join Date: Aug 2009 Location: Long Island New York Posts: 4	Galavoxx Great to hear. I hope it gets even better for you tomorrow.