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11-21-2012, 04:13 AM | #145 |
Drives: Racin' yaris :D Join Date: Nov 2012
Location: Trois-Rivières, Qc
Posts: 86
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Hey guys, What is the difference between 4-2-1 and 4-1, in performance I mean
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11-21-2012, 10:23 AM | #146 |
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Drives: light blue liftback Join Date: Aug 2009
Location: so cal
Posts: 926
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Depends on how they are designed, but if both are designed correctly there should be almost no difference.
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11-21-2012, 10:46 AM | #147 | |
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Drives: 2012 Yaris L 2dr 5sp Join Date: Apr 2012
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Quote:
A 4-2-1 tri Y header pairs up sequentially firing cylinders 2-1 and 3-4 so that the exhaust pulse from one helps to draw exhaust from the other. Then the combined 2-1 and 3-4 pairs join to help scavange each other... Practically speaking, the headers are too short to make a lot of difference. But that's where namer comes in... |
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11-21-2012, 12:08 PM | #148 |
Form>Function
Drives: 07 Flint Sedan Join Date: Dec 2009
Location: Tampa
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The 4-1 is supposed to delay the power increase until higher in the powerband. The 4-2-1 is supposed to give a midrange bump. On our tiny cars you probably would never notice a difference. I love my DC header. Anytime I'm above 4k I'm just roaring and pulling hard for a yaris lol.
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11-21-2012, 12:20 PM | #149 |
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Drives: 2012 Yaris L 2dr 5sp Join Date: Apr 2012
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I actually did notice a difference...
...as I climb a steep 1/4 mile hill in 2nd gear to get to my house. It's always the same hill, so that's constant. And driving up it everyday I have a good feeling for the resistance. The header definitely helped the engine make it up the hill easier. If you start climbing under 2,000 rpm, the engine labors sluggishly. But anything over 2,000 and it gains rpms much easier and climbs more easily than the stock header which feels like it's holding back at the same rpms. |
11-21-2012, 12:36 PM | #150 |
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Drives: 07 Yaris Turbo Join Date: May 2007
Location: Canoga Park, CA
Posts: 14,859
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^ An aftermarket header will certainly make a difference over stock, but I doubt you can feel any difference BETWEEN aftermarket headers. You just can't feel 1-2 horsepower, in my opinion.
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11-21-2012, 12:36 PM | #151 |
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Drives: 07 Yaris Turbo Join Date: May 2007
Location: Canoga Park, CA
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TRYaris is that your car in your avatar?
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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. |
11-21-2012, 01:32 PM | #152 |
0-60 in slow
Drives: light blue liftback Join Date: Aug 2009
Location: so cal
Posts: 926
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Basically what Cali said.
There is a maximum of about 12" to work with and an ideal length of about 35" so most of the ots headers compensate by increasing the volume of tube which in essence give some of the same effect as increasing length but reduces scavenging at lower rpms. Now this motor is relatively small displacement with a good torque management system going to a larger diameter tube won't hurt you as bad as it would on a larger engine. So not wanting to give up anywhere in the powerband while still gaining some up top is the reason I decided to design and build my own header. As far as header type is concerned both a 4-2-1 and a 4-1 will accomplish the same goal but each design has its own advantages but both of them can produce near the same power and torque so there isn't a real advantage to choosing either one aside from packaging constraints, and a 4-1 is simply easier to package with the effecting lengths required. |
11-21-2012, 02:05 PM | #153 |
Drives: Racin' yaris :D Join Date: Nov 2012
Location: Trois-Rivières, Qc
Posts: 86
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11-21-2012, 03:01 PM | #154 | |
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Drives: 07 Flint Sedan Join Date: Dec 2009
Location: Tampa
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Quote:
Tr that pic I think is sporting a MI Hood visor. |
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12-01-2012, 09:20 PM | #155 |
Drives: soarer Join Date: Feb 2011
Location: Beautiful British Columbia
Posts: 954
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This is what I received yesterday
http://photo.qip.ru/users/tolmach/96608749/129617602/ Same part number but Dc logo seems to be on the fourth tube as compared to this one (stole this pic from someone here) - here logo is on the third tube http://photo.qip.ru/users/tolmach/96608749/129617601/ have not tried installing it yet, but there seems to be enough space between the hole for the O2 sensor and top bracket Overall build quality of mine is not very impressive (kinda very average) as compared to the WR one |
12-01-2012, 09:33 PM | #156 |
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Drives: 2012 Yaris L 2dr 5sp Join Date: Apr 2012
Location: Los Angeles
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That's one thing I really like about the Weapon R. It's precise. You could cut your finger on that sharp knife edge where the two main tubes are joined...
But as far as performance, it doesn't matter. |
12-01-2012, 10:20 PM | #157 |
0-60 in slow
Drives: light blue liftback Join Date: Aug 2009
Location: so cal
Posts: 926
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That's not a good thing, air doesn't like sharp edges.
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12-01-2012, 10:56 PM | #158 |
Super Moderator
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I don't think it would make that much of a difference in our case either way.
Any aftermarket header should prove to be at least slightly better than stock, right?
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Last edited by tk-421; 12-02-2012 at 12:47 AM. |
12-01-2012, 11:07 PM | #159 |
0-60 in slow
Drives: light blue liftback Join Date: Aug 2009
Location: so cal
Posts: 926
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the slight knock it causes in flow won't make much of a difference.
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12-02-2012, 12:49 AM | #160 |
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Drives: 2012 Yaris L 2dr 5sp Join Date: Apr 2012
Location: Los Angeles
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12-02-2012, 01:41 PM | #161 | |
Drives: soarer Join Date: Feb 2011
Location: Beautiful British Columbia
Posts: 954
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Quote:
Mine looks nothing like this inside (build quality wise) (( Hopefully, will still do its job |
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12-02-2012, 01:55 PM | #162 |
0-60 in slow
Drives: light blue liftback Join Date: Aug 2009
Location: so cal
Posts: 926
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I wouldn't worry, all of the aftermarket headers lack a ventur,i so the collector looking bad wol make almost no difference.
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