Go Back   Honda-Tech > Honda and Acura Technical Forums > Forced Induction
Sign in using an external account
Register Forgot Password?
Search


Welcome to Honda-Tech!
Welcome to Honda-Tech.com.

You are currently viewing our forums as a guest, which gives you limited access to view most discussions and access our other features. By joining our community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join the Honda-Tech community today!


Reply
 
 
 
submit to reddit
 
LinkBack Thread Tools Search this Thread
Old 02-22-2003, 11:35 AM   #1
Junior Member
 
Therumblingteg's Avatar
 
Join Date: Feb 2003
Posts: 129
iTrader Rating: (0)
Default What is better for a intake manifold, a square plenum, or a round one?

what about the runners, round or square? I was thinking about making one, but then some one started a disscussion on another site, where Polk performance made this square one. Since this site has proff drag racers and fabcraters I though I hear it from you guys. Click the image to open in full size.

Click the image to open in full size.
They are built really well, but just wana know what you guys think.


[Modified by Therumblingteg, 8:36 PM 2/22/2003]
Therumblingteg is offline   Reply With Quote
Old 02-22-2003, 12:05 PM   #2
Member
 
Join Date: Nov 2001
Location: nj
Posts: 3,140
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (Therumblingteg)

A square plenum isn't really too functional.
ekb18c is offline   Reply With Quote
Old 02-22-2003, 01:13 PM   #3
Honda-Tech Member
 
Join Date: Jul 2002
Location: Kills.
Posts: 1,672
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (ekb18c)

Quote:
A square plenum isn't really too functional.
Well gee, that explains it! Thanks! Oh hey, how about some explination, eh?
Loco Honkey is offline   Reply With Quote
Old 02-22-2003, 01:31 PM   #4
Member
 
Join Date: Nov 2001
Location: nj
Posts: 3,140
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (Loco Honkey)

Sarcasim will get you no where!

I was going to go into more detail but after reading your comment, I won't!

Have a nice day.

edit- Therumblingteg if you want an explanation IM me and I'll explain it in more detail.


[Modified by ekb18c, 2:32 PM 2/22/2003]
ekb18c is offline   Reply With Quote
Old 02-22-2003, 02:40 PM   #5
I am a bad person
 
Join Date: Aug 2002
Location: South Florida
Posts: 3,466
iTrader Rating: (0)
Send a message via AIM to MotorMatrix.com
Default Re: What is better for a intake manifold, a square plenum, or a round one? (ekb18c)

The round plenum intake is more beneficial.I think turbulence is the reason why you dont want the forced air to pushed into a wall at cylinder 1 int he plenom. I think the harmonics of the square one is not a good as a round one if thats the correct technical term.Maybe Tony 1 can explain this more technically if I am wrong. We build ours with large round plenums for 4 cylinders and with large throttle body openings where it tapers down to cylinder one to reduce unwanted tq but more Hp on 6 cylinders.
MotorMatrix.com is offline   Reply With Quote
Old 02-22-2003, 03:01 PM   #6
Junior Member
 
Therumblingteg's Avatar
 
Join Date: Feb 2003
Posts: 129
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (ekb18c)

I am not allowed to im, or any thing execpt make 5 posts.
Therumblingteg is offline   Reply With Quote
Old 02-22-2003, 05:53 PM   #7
Honda-Tech Member
 
glagola1's Avatar
 
Join Date: Jul 2001
Location: atlanta, ga, usa
Posts: 721
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (Therumblingteg)

I've read that paralelle walls in the plenum will resonate and that resonation is bad. I can only assume that it disrupts the velocity of the charge air some how. That's all I know.
glagola1 is offline   Reply With Quote
Old 02-22-2003, 06:00 PM   #8
Honda-Tech Member
 
Diablo Tejano's Avatar
 
Join Date: Nov 2002
Posts: 195
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (ekb18c)

Quote:
Sarcasim will get you no where!

I was going to go into more detail but after reading your comment, I won't!

Have a nice day.
[Modified by ekb18c, 2:32 PM 2/22/2003]
Lets not be a Knowledge-Nazi. I mean jesus, if you know the answer to the question and the why of it, why not share? Because one person made a sarcastic comment?Click the image to open in full size. Look dude, i know you know your ****, so why not just take 30 seconds to type an answer so we can all be less dumb. (or at least just me)

Thanks,
James


[Modified by bluboy, 9:01 PM 2/22/2003]
__________________
Will work for food,
Or kill you for money.
Diablo Tejano is offline   Reply With Quote
Old 02-22-2003, 07:19 PM   #9
mos
Honda-Tech Member
 
mos's Avatar
 
Join Date: Sep 2002
Location: 90210, CA, usa
Posts: 2,720
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (bluboy)

One thing any highschool student could tell you, is that for a square and a circle with the same area, the circle has a smaller circumfrence. A tube with a square cross section is going to have more surface area than cylindrical tube. Surface area = friction.

I'm not going to pretend to know anything about resonances or fluiddynamics/aerodynamics. I'll let others do that. Click the image to open in full size.
__________________
Project toys: P2J ED9, PR4 DA9, GSXR
mos is offline   Reply With Quote
Old 02-23-2003, 08:28 AM   #10
 
Join Date: Jan 2003
Location: Rochester, MN, us
Posts: 179
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (mos)

...Both round and square/rectangular type intakes have beenused successfully in engines producing 600-1200 rwhp on both Hondas, Mitsu's and Supras...Its more about the plenum Volume, runner diameter and transition from Plenum to runner and Throttle body size...

SuperT is offline   Reply With Quote
Old 02-23-2003, 08:35 AM   #11
Honda-Tech Member
 
SIXTYdashONE's Avatar
 
Join Date: Jun 2002
Location: n00 Jersey, USA
Posts: 16,757
iTrader Rating: (0)
Send a message via AIM to SIXTYdashONE
Default Re: What is better for a intake manifold, a square plenum, or a round one? (bluboy)

Quote:
Lets not be a Knowledge-Nazi. I mean jesus, if you know the answer to the question and the why of it, why not share?
I see you have met the realColin Click the image to open in full size.

I personally never understood how those square plenums flowed worth a ****, so i was never interested in one, ever.. If anyone knows what mine looks like, Or Colins for that matter, a Custom Mani was the choice in the matter...
__________________
10.57 @ 141mph (2003) SFWD OG'
SIXTYdashONE is offline   Reply With Quote
Old 02-23-2003, 08:42 AM   #12
 
Zero_son's Avatar
 
Join Date: Feb 2003
Location: Right behind you, USA
Posts: 141
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (SuperT)

Quote:
...Both round and square/rectangular type intakes have beenused successfully in engines producing 600-1200 rwhp on both Hondas, Mitsu's and Supras...Its more about the plenum Volume, runner diameter and transition from Plenum to runner and Throttle body size...
Not quite. It has a lot to do with surface area, and the friction it cause's which slows down the velocity of the incoming air. Velocity is what you want, and with square runners you're going to have waaay too much surface area with that long of a runner to keep the velocity up. Unless of course you can flow that much air in the first place. Which is next to impossible with-out some crazy boost levels and a fully-worked head, but on the street forget about low-end with it. Get a rounded one so you can still have some power left for daily driving if it is a daily beast.

As far as the ports go with being squared off. They are squared on the inner and outer radius's to allow higher velocities with out having to expand the the opening around the bends, which would be very hard to produce en~mass production style. There's more to it, but I won't go into it unless you wish to hear it, ok? Click the image to open in full size.

BTW - I know it was an overly watered down version of what happens so please keep your trash talking to yourself.
__________________


Humanities only problem is that it strives to hold itself back. Let go of your fears, and seek understanding that all is right in front of you. All you ever have to do is open your mind to visualize it. Relax and release your inhibitions into order to progress.
-Many words of wisdom by: ~ ME ~
Zero_son is offline   Reply With Quote
Old 02-23-2003, 09:20 AM   #13
Honda-Tech Member
 
Full-Race Geoff's Avatar
 
Join Date: May 2001
Location: FULL RACE, AZ, USA
Posts: 4,719
iTrader Rating: (0)
Default Re: What is better for a intake manifold, a square plenum, or a round one? (Therumblingteg)

i dont like that manifold one bit. I met the designer at Palmdale last november, he had no clue what he was talking about and hadnt the slightest idea about anything regarding fluid dynamics.

round is very important here.
__________________
Full-Race Motorsports

Facebook | YouTube
Full-Race Geoff is offline   Reply With Quote
Old 02-23-2003, 10:09 AM   #14
Honda-Tech Member
 
Join Date: Feb 2001
Location: Northern, VA
Posts: 1,263
iTrader Rating: (0)
Send a message via AIM to SlowTeg
Default Re: What is better for a intake manifold, a square plenum, or a round one? (FFgeoff)

Hmm.. those manifolds look alot like the extreme dsm manifolds I've seen.. Anyway, besides the square shape, isn't the plenum a little small? Looks too small IMO, but what do I know..

-Mike
SlowTeg is offline   Reply With Quote
 
 
 
submit to reddit
Reply

Tags
box, dsm, expand, intake, manifold, manifolds, openings, plenum, plenums, rectangular, round, rounded, size, square, transition, volume

Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
88 crx si chassis harness VTECdohcter Honda CRX / EF Civic (1988-1991) 7 07-09-2010 07:57 AM
Auto D16Y8 intake manifold onto D16Z6 ?'s brentmc79 Honda Civic/Del Sol (1992 - 2000) 7 04-20-2009 03:58 PM
REVHARD MFG PRODUCTS camp1320.com Forced Induction 485 06-10-2008 09:51 AM
96-98 Civic Fog Lights. Square or Round? 1996-1998 Foglights OEM Guam_CiviC619 Honda / Acura 54 04-30-2008 09:10 AM
Rev Hard Intake Manifolds - Finally In Stock - $295 Shipped - B16/B18 turbo-kits-com Forced Induction 11 01-01-2006 05:05 PM



All times are GMT -8. The time now is 12:03 AM.



2014 Copyright, InternetBrands Inc.
Powered by vBulletin® Version 3.8.7 AC1
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.

Honda and the Honda marquee are registered trademarks of the American Honda Motor Company, Inc. Neither American Honda Motor Company nor its subsidiaries or affiliates shall bear any responsibility for Honda-Tech.com content, comments, or advertising. Honda-Tech.com is not affiliated with American Honda Motor Company in any way. American Honda Motor Company does not sponsor, support, or endorse Honda-Tech.com in any way. Copyright/trademark/sales mark infringements are not intended or implied.
Emails & Contact Details