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Forum nameTurbo/Nitrous Tech
Topic subjectClarification of my post regarding obx manifold
Topic URLhttps://forums.2gnt.com/dcboard.php?az=show_topic&forum=i8&topic_id=97688
97688, Clarification of my post regarding obx manifold
Posted by CanadianCarGuy, Oct-07-06 03:41 PM
Ok I misworded my post in people's opinion of obx manifold.

I said that match porting/polishing and adding another set of injectors was all you needed for making big power. This is the cheapest way of providing enough fuel for boost. another set of injectors can be had for cheap on ebay along with electronics to control them. Cheaper than buying new larger injectors, while not having idle problems and other problems that can come up.

And when I said that the fuel rail, obx manifold, fuel rail would make for a smaller range of torque, I meant that the low rpm range of the power band will suffer slightly, while the upper end of the RPM range will benefit way more. I have seen dyno charts of a honda with ported intake and then have the intake manfold switched to a larger volume venom type intake manifold. The ported intake showed a constant power gain throughout the entire RPM range, while the venom actually showed a loss of power up to 2200 rpm, then it showed a gain at a steeper rate towards redline. This was on a naturally aspirated v-Tech in Calgary, Canada.

The reason for having wideband sensors in each exhaust runner is because not all cylinders have the same air/fuel ratio, if you have an unlimited budget, who cares about replacing o2 sensors all the time. My turbo buick always has leaner mixtures in the rear two cylinders, those are almost always the pistons that get damaged under detonation.

someone specifically asked what would make a good manfold for the 420A. Plain simple points and concepts that would make a better 420A manifold. I didn't mean to offend anyone.

I am crawling back to my hole now....
97689, RE: Clarification of my post regarding obx manifold
Posted by Collente, Oct-07-06 05:15 PM
I wasn't trying to be a dick, but you still haven't said much my friend.

I was trying to find out WHAT would make a good manifold for us.
Shorter runners =?
More volume, where and why?
Thinner volume to wider make a difference, other way around?
What makes less torque and better top end as apposed to more torque, ect ect..
I know our manifold sucks, but the venom seemed to take care of a lot..
* Smooth internals
* More volume in upper plenum
* Larger runners
* One piece, so less obstruction
* It's pretty ;)

the inside of our manifold is bumpy, dirty from as shit from stock egr, small runners, ect.

I know our head flows a lot, what's the best way to maximize this? I know that some of you guys KNOW WHAT AND WHY but most of us do not...
Please educate us with as much info as possible, leave it to us to rummage through the dump and decipher, for at least the info is present.


Nick
97RS
97693, RE: Clarification of my post regarding obx manifold
Posted by JustOne, Oct-07-06 06:21 PM
RRREEEAAAADDDD MMMMMMEEEEEE

http://www.amazon.com/Maximum-Boost-Turbocharger-Engineering-Performance/dp/0837601606/sr=8-1/qid=1160281211/ref=pd_bbs_1/104-3044907-7995907?ie=UTF8&s=books
97694, RE: Clarification of my post regarding obx manifold
Posted by Collente, Oct-07-06 06:46 PM
u dick ;)

lol

Nick
97RS
97698, RE: Clarification of my post regarding obx manifold
Posted by turbo8u, Oct-08-06 02:14 PM
even your clarification needs clarification, geeze.

i'll stay out of this.
97706, RE: Clarification of my post regarding obx manifold
Posted by CanadianCarGuy, Oct-09-06 12:35 PM
There is a book called "The Scientific Design of Intake and Exhaust Systems" available at Amazon.com. This book will explain everything.
97709, RE: Clarification of my post regarding obx manifold
Posted by 97eclipse97, Oct-09-06 03:32 PM
Originally posted by turbo8u
even your clarification needs clarification, geeze. i'll stay out of this.


Well I will start with the obvious:

How can a "larger" set of injectors be more expensive than buying another set of injectors, some kind of controller, and a new intake manifold? There is not a big difference in cost in injectors going from size to size. For example: (from the FIC website)

650 cc Peak & Hold #125-650 Set/4 $269

750 cc Peak & Hold #125-750 Set/4 $269

850 cc Peak & Hold #125-850 Set/4 $269

950 cc Peak & Hold #125-950 Set/4 $295

1000cc Peak & Hold #125-1000 Set/4 $310
97713, RE: Clarification of my post regarding obx manifold
Posted by Keith2172, Oct-10-06 04:58 AM
When is someone going to bite the bullet, cut a giant hole in their hood, and make a 4-1 intake manifold? That would solve the issue of the passenger side cylindar (#1?) being the leanest. Oh how I wait for the day when a pro-mod hood scoop is glassed onto a 2GNT hood.
97716, RE: Clarification of my post regarding obx manifold
Posted by turbo8u, Oct-10-06 02:10 PM
Originally posted by Keith2172
Oh how I wait for the day when a pro-mod hood scoop is glassed onto a 2GNT hood.


lol! kidding, right? :wary