Megan Header Dyno Results - Page 3 - Toyota Yaris Forums

spkrman · 01-05-2007, 05:25 PM

i think we'll have to wait for some of hte scion products to come on over... there are gains shown with headers over there, not sure whats up here.

RossP · 01-06-2007, 07:46 AM

TBH I think you might have a bit of a dodgy dyno. What make was the dyno?

gr8yaris · 01-08-2007, 10:03 PM

From what I have learned so far from my other car projects, the exhaust mod works best in conjunction with an intake mod. Although individually, each can individually improve performance, one is inter-dependent on the other for maximum combined performance outcome.

There's really not much sense in making the exhaust diameter (e.g.: header) exit much larger if there is no current increase in the a/f volume to start with or vice-versa. Using the Bernoulli's principle, the increase in the pipe diameter does not neccessarily improve flow. However, if there is an increase in the a/f volume (because of e.g.: CAI or Forced Induction) then improving the corresponding exit (exhaust) is of proportionate benefit.

largeorangefont · 01-08-2007, 10:09 PM

If the individual runners are larger than stock, you will lose power until very high RPMS. On a low powered engine like this, you wont have any noticeable gains until you do other mods such as intake and full exhaust. A 4-2-1 header might be better for this application.

The design of the Megan and the OEM manifold look very similar. It looks like the Megan has slightly larger diameter runners, which would explain the results.

That being said, the OEM manifold looks pretty well designed for what it is.

CASTREX · 01-09-2007, 12:54 PM

Any one knows anything about the Weapon R header? That's a 4-2-1 desing. It was supposed to be out early this year.

ChinoCharles · 01-09-2007, 01:07 PM

Nope.

Oh, and it is official... the Dyno was OFF. Confirmed by Mustang Dyno themselves, and they will be out yet again to look at it soon.

Fourth gear in the Yaris is 0.969:1, so fourth being closest to a 1:1 gear ratio, that is the gear you should use to dyno test Yarii. Well, our fourth gear pull read at 125 HP, so that means this dyno is screwed up... off by about 40 HP. Easy to miss when tuning a 400 WHP car, but it became extremely apparent when they threw the little-Yaris-that-couldn't on there. MD's peeps are coming to look at it soon, and then I will be going back yet again to retest the car. Hopefully by then I will have the pulley in my posession so I can do before, w/ header, and w/ header and pulley runs. It would be interesting to see if the pulley can negate the low-end losses from the header.

I'm dreadfully fucking sorry for all of this.

Fastnx · 01-09-2007, 03:13 PM

Quote:

Fourth gear in the Yaris is 0.969:1, so fourth being closest to a 1:1 gear ratio, that is the gear you should use to dyno test Yarii

Gearing does not matter.

Did you know that after the power leaves the output shaft, it goes through the final drive where it is reduced again by approximately 4:1?

largeorangefont · 01-09-2007, 03:35 PM

Quote:

Originally Posted by Fastnx

Gearing does not matter.

Did you know that after the power leaves the output shaft, it goes through the final drive where it is reduced again by approximately 4:1?

On certain types of dynos it does matter. It depends on how the dyno calculates load. They assume that the transmission ratio is 1:1

If you did the test back to back on the same day, I would consider the results valid. Even though the dyno read high, it is better than comparing before and after numbers on 2 differend dynos or different days.

Galavoxx · 01-09-2007, 06:00 PM

Quote:

Originally Posted by CASTREX

Any one knows anything about the Weapon R header? That's a 4-2-1 desing. It was supposed to be out early this year.

I was the test subject for the first header and they told me about three months. That was in November some time. They are supposed to call me when it's done. Who knows if they will. I'm just waiting...

ChinoCharles · 01-09-2007, 07:34 PM

Quote:

Originally Posted by largeorangefont

On certain types of dynos it does matter. It depends on how the dyno calculates load. They assume that the transmission ratio is 1:1

If you did the test back to back on the same day, I would consider the results valid. Even though the dyno read high, it is better than comparing before and after numbers on 2 differend dynos or different days.

The first statement is correct. On Mustang Dynos, you need to know your gear ratio. I didn't know this until I got there of course, hence why we ended up doing the pulls in third. Now I know, so next time we will use fourth.

I second what you said also about the results being valid. Viewing the original results as a ratio rather than cold hard numbers, you can apply those to the expected 80 or so WHP. Having said that, we are still going to start the whole process over. I want a real baseline so I can document what each mod does to this car throughout. She wont be stock much longer.

Fastnx · 01-09-2007, 09:20 PM

You guys do not know what you are talking about. You are dyno newbies, I have about 30 hours of experience on a 4 different kinds of dynos.

Do you even know what a final drive is? Do you really think the wheel speed is almost the same as the crankshaft speed?

If there is an RPM pickup, you do not need to know the gear ratio.

ChinoCharles · 01-09-2007, 09:44 PM

First of all, settle down.

Second of all, I hardly believe 30 hours designates you as an expert there princess.

Third, I am a dyno noobie, and I don't profess to be anything else... unlike yourself, who apparently believes 30 whole hours makes you an expert. There are people that spend more time on a dyno in a week than you have in your life, my trusted tech included. Apparently he doesn't know as much as you, though.

Everyone thinks they're a fucking expert. Give me a break. Didn't your mother ever tell you no matter how much you THINK you know, there is always someone out there who knows more... or in your case, a whole lot of people.

vodkalush · 01-09-2007, 10:01 PM

Listen I've touched a computer and use it atleast 4hrs a week and since I've been working with them for 2yrs I am a computer expert!!!

but really, simmer. All around I think if anyones followed this thread then you would know that this is chino's first dyno experiance (unless I missed something; in which case go suck an egg) so there are bond to be some issues, and 30hrs experience does not make you an expert in anything... unless your talking about 30 straight hours of making some grilled cheese goodness.... ummm grilled cheese :drools:

either way lets try and keep it friendly boys, we're all here to learn so some mistakes are bond to happen. Well it's been fun and all but its time to go watch "Children of Men" and passout on my couch.

largeorangefont · 01-10-2007, 12:00 AM

Quote:

Originally Posted by Fastnx

You guys do not know what you are talking about. You are dyno newbies, I have about 30 hours of experience on a 4 different kinds of dynos.

Do you even know what a final drive is? Do you really think the wheel speed is almost the same as the crankshaft speed?

If there is an RPM pickup, you do not need to know the gear ratio.

I've had 130 hours across 5 dynos brands and about 10 facilities, and I'm no expert. Shut up, you don't know what you are talking about. Not every dyno in the world is a Dynojet. If that was the case you would be correct.

Fastnx · 01-10-2007, 01:02 PM

way to back up your opionions with facts.

Again, find out what a 'final drive' is and then see what you think.

Russelt3hPirate · 01-10-2007, 01:11 PM

Chino,

would you be willing to do the following?

Go back to stock, Dyno
Header, Dyno
Pulley and Header, Dyno
stock headers and pulley, Dyno

and how is the pulley making power on the yaris and not on every other car in the world? would a lightweight flywheel make more power too?

largeorangefont · 01-10-2007, 01:11 PM

Quote:

Originally Posted by Fastnx

way to back up your opionions with facts.

Again, find out what a 'final drive' is and then see what you think.

Way to back up your opinions with misinformation and crying.

GENERALLY, changing the final drive on your car shouldn't affect peak horsepower, only the curve. There are some dynos with calibrations that will change HP output if you put on a shorter final drive. This is obviously incorrect as changing the final drive does not change HP. The general consensus is to dyno the car in the gear that is closest to 1:1 to keep results similar across all types of cars. Dynoing a car in 2nd and another in 4th gear would give two completely different curves, and be an invalid comparison of the 2 cars.

ChinoCharles · 01-10-2007, 01:15 PM

Again, this isn't my opinion, this is the opinion of the man that owns the dyno I run at. He tells me that his particular dyno relies on the fact that the car is run in a gear that is as close to a 1:1 ratio as possible.

In 8 posts on these forums, you haven't posted one bit of usable information, so you have no room to talk about facts.

If it makes you feel any better, I had no idea what a final drive was until you mentioned it and I looked it up. Now I have yet another thing I can learn from my trusted dyno EXPERT when I see him next. Hooray.

For anyone that doesn't know and would like to...

http://auto.howstuffworks.com/differential.htm

01-08-2007, 10:03 PM	#39
gr8yaris Drives: 07 Yaris Hatchback Join Date: Jan 2007 Location: New Jersey Posts: 16	From what I have learned so far from my other car projects, the exhaust mod works best in conjunction with an intake mod. Although individually, each can individually improve performance, one is inter-dependent on the other for maximum combined performance outcome. There's really not much sense in making the exhaust diameter (e.g.: header) exit much larger if there is no current increase in the a/f volume to start with or vice-versa. Using the Bernoulli's principle, the increase in the pipe diameter does not neccessarily improve flow. However, if there is an increase in the a/f volume (because of e.g.: CAI or Forced Induction) then improving the corresponding exit (exhaust) is of proportionate benefit. __________________ 2007 White Liftback 5-speed Tanabe DF 2" lowering springs, 205/50-15 on 15x6.5 Konig Helium, TRD rear sway bar, 15mm Hub spacer http://picasaweb.google.com/USAntonio/MyGarage#

01-09-2007, 10:01 PM	#49
vodkalush I drive a yarrrris View User's Garage Drives: 07 Sedan Polar White Join Date: Sep 2006 Location: Rochester, NY Posts: 1,009	Listen I've touched a computer and use it atleast 4hrs a week and since I've been working with them for 2yrs I am a computer expert!!! but really, simmer. All around I think if anyones followed this thread then you would know that this is chino's first dyno experiance (unless I missed something; in which case go suck an egg) so there are bond to be some issues, and 30hrs experience does not make you an expert in anything... unless your talking about 30 straight hours of making some grilled cheese goodness.... ummm grilled cheese :drools: either way lets try and keep it friendly boys, we're all here to learn so some mistakes are bond to happen. Well it's been fun and all but its time to go watch "Children of Men" and passout on my couch. __________________ Docotrs say all the drikning has mesesd up my seplilng and radieng Get your YarisWorld.com stickers here!!! The Official Toyota Thailand Accessories Order Thread will work for parts

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01-05-2007, 05:25 PM	#37
spkrman Banned View User's Garage Drives: 1 Join Date: Nov 2006 Location: 2 Posts: 1,476	i think we'll have to wait for some of hte scion products to come on over... there are gains shown with headers over there, not sure whats up here.

01-06-2007, 07:46 AM	#38
RossP Drives: MK I Vitz 1.0l F Package Join Date: Jun 2006 Location: Paphos, Cyprus Posts: 81	TBH I think you might have a bit of a dodgy dyno. What make was the dyno?

01-08-2007, 10:09 PM	#40
largeorangefont Break'em off some. View User's Garage Drives: 07 Yaris LB, 04 Cobra Join Date: Jan 2007 Location: So Cal, OC Posts: 854	If the individual runners are larger than stock, you will lose power until very high RPMS. On a low powered engine like this, you wont have any noticeable gains until you do other mods such as intake and full exhaust. A 4-2-1 header might be better for this application. The design of the Megan and the OEM manifold look very similar. It looks like the Megan has slightly larger diameter runners, which would explain the results. That being said, the OEM manifold looks pretty well designed for what it is.

01-09-2007, 12:54 PM	#41
CASTREX Who said Yaris was slow? View User's Garage Drives: Yaris T-Sport 2008 Join Date: Nov 2006 Location: Costa Rica Posts: 1,287	Any one knows anything about the Weapon R header? That's a 4-2-1 desing. It was supposed to be out early this year.

01-09-2007, 01:07 PM	#42
ChinoCharles Banned Drives: LB Join Date: Jul 2006 Location: OH Posts: 7,787	Nope. Oh, and it is official... the Dyno was OFF. Confirmed by Mustang Dyno themselves, and they will be out yet again to look at it soon. Fourth gear in the Yaris is 0.969:1, so fourth being closest to a 1:1 gear ratio, that is the gear you should use to dyno test Yarii. Well, our fourth gear pull read at 125 HP, so that means this dyno is screwed up... off by about 40 HP. Easy to miss when tuning a 400 WHP car, but it became extremely apparent when they threw the little-Yaris-that-couldn't on there. MD's peeps are coming to look at it soon, and then I will be going back yet again to retest the car. Hopefully by then I will have the pulley in my posession so I can do before, w/ header, and w/ header and pulley runs. It would be interesting to see if the pulley can negate the low-end losses from the header. I'm dreadfully fucking sorry for all of this.

01-09-2007, 09:20 PM	#47
Fastnx Drives: Nissan NX2000 Join Date: Nov 2006 Location: Canada Posts: 12	You guys do not know what you are talking about. You are dyno newbies, I have about 30 hours of experience on a 4 different kinds of dynos. Do you even know what a final drive is? Do you really think the wheel speed is almost the same as the crankshaft speed? If there is an RPM pickup, you do not need to know the gear ratio.

01-09-2007, 09:44 PM	#48
ChinoCharles Banned Drives: LB Join Date: Jul 2006 Location: OH Posts: 7,787	First of all, settle down. Second of all, I hardly believe 30 hours designates you as an expert there princess. Third, I am a dyno noobie, and I don't profess to be anything else... unlike yourself, who apparently believes 30 whole hours makes you an expert. There are people that spend more time on a dyno in a week than you have in your life, my trusted tech included. Apparently he doesn't know as much as you, though. Everyone thinks they're a fucking expert. Give me a break. Didn't your mother ever tell you no matter how much you THINK you know, there is always someone out there who knows more... or in your case, a whole lot of people.

01-10-2007, 01:02 PM	#51
Fastnx Drives: Nissan NX2000 Join Date: Nov 2006 Location: Canada Posts: 12	way to back up your opionions with facts. Again, find out what a 'final drive' is and then see what you think.

01-10-2007, 01:11 PM	#52
Russelt3hPirate l33t3st Asshole Drives: MY07 Yaris Liftback Join Date: Nov 2006 Location: Epcot Posts: 588	Chino, would you be willing to do the following? Go back to stock, Dyno Header, Dyno Pulley and Header, Dyno stock headers and pulley, Dyno and how is the pulley making power on the yaris and not on every other car in the world? would a lightweight flywheel make more power too?

01-10-2007, 01:15 PM	#54
ChinoCharles Banned Drives: LB Join Date: Jul 2006 Location: OH Posts: 7,787	Again, this isn't my opinion, this is the opinion of the man that owns the dyno I run at. He tells me that his particular dyno relies on the fact that the car is run in a gear that is as close to a 1:1 ratio as possible. In 8 posts on these forums, you haven't posted one bit of usable information, so you have no room to talk about facts. If it makes you feel any better, I had no idea what a final drive was until you mentioned it and I looked it up. Now I have yet another thing I can learn from my trusted dyno EXPERT when I see him next. Hooray. For anyone that doesn't know and would like to... http://auto.howstuffworks.com/differential.htm