macs pipe and header - Page 2 - RCCanada - Canada Radio Controlled Hobby Forum
RCCanada - Canada's Radio Control Hobby Forum
Engines Discuss engines

Closed Thread
Thread Tools Display Modes
Old 10-01-2005, 07:58 PM   #11
Ed Smith

Feedback: / %
Posts: n/a
Total Props: 0

       Remove this ad - become a site supporter!
The pipe shown is a fairly moderate tuned pipe, as evidenced by the long parallel portion. In other words it will handle a wide rpm range without dropping out of that range. The back pressure in a pipe starts at the beginning of the decreasing diameter. The backpressure is present all the way along the pipe from that point towards the engine. from a pressure standpoint the position of the fitting could be anywhere from that point towards the engine. From a mechanical standpoint some thought is required. If the fitting is installed as I previously suggested it should be OK. However I have experienced fittings blowing out of thin wall pipes and the pipes breaking at the hole position. So the thicker the material the fitting is screwed into the better.

In your case I would place the fitting in the rectangular plate/header that is screwed to the engine. In the middle on top or whichever is the most convenient position for your installation. If you would rather believe others then do it anyway, the hole can always be blocked with a screw and the fitting moved. Then you will have learned something. You will then be an expert on tuned pipe pressure fitting placement.

Ed S
  Quick reply to this message.

Sponsored Links - Subscribe to remove this ad.
Old 10-01-2005, 11:32 PM   #12
RCC Pro Contributor
Canhos's Avatar
I am: Mike Gyger
Join Date: Jul 2005
Location: Chilliwack BC

Feedback: 0 / 0%
Posts: 1,563
Total Props: 0
When you say reliability, do you mean your engine quits? I've only ran a couple engines with tuned pipes, never for racing, just to be obnoxious. I use the MACS pipes as well. The ones I use are both tapped just where the pipe gets to it's largest diameter. This provides for a reliable run. As I stated previously, I had read about the header tapping. For a drawing of what MACS has to say see

Canhos is offline   Quick reply to this message.
Old 10-02-2005, 09:46 AM   #13
RCC Junior Contributor
Rosisco's Avatar
I am: Ross d
Join Date: Jul 2003
Location: Armstrong bc
Radio of choice:
# of RCs: 12

Feedback: 0 / 0%
Posts: 131
Total Props: 0
Has anyone used a Macs header and quiet pipe on an OS 91fx?
Are they quiet???
Rosisco is offline   Quick reply to this message.
Old 10-02-2005, 06:11 PM   #14
I am: Boolean21
Join Date: Sep 2002
Location: Singapore

Feedback: 0 / 0%
Posts: 38,228
Total Props: 56
I use a macs quite pipe with a 46fx (the 7.5 cc pipe). It turns a 12x6 apc prop at 13K, running 10% fuel. If there are other planes in the air I sometimes can't hear it. It defintely takes the edge off the exhaust sound.
I'd consider the Just Engines ( "purple pipes" as well.
PurgatorY is offline   Quick reply to this message.
Old 10-16-2005, 05:29 AM   #15
RCC Expert Contributor
I am: jeff t
Join Date: May 2004
Location: london ontario
Radio of choice:
Specktrum DX18
# of RCs: 15

Feedback: 3 / 100%
Posts: 879
Total Props: 3

Tisk Tisk Bryan pipes are not allowed in combat, bad boy
Green side is definitely not up
canadianice is offline   Quick reply to this message.
Old 10-16-2005, 09:59 AM   #16
RCC Supreme Contributor
nony's Avatar
Join Date: Sep 2002
Location: the Park, Ab.

Feedback: 0 / 0%
Posts: 4,339
Total Props: 0
I have seen pressure taps in the header pipe, but a little ways out, not at the flange. I've done two with the tap in the parallel section of the pipe. It is awhile ago, but it looks like I just screwed the brass fitting into the aluminum wall (I don't have any taps), and it looks like I used epoxy or something to seal it...what ever it is, it is holding well...I just went down to find it, and gave it a is in there solidly!

The sooner you fall behind, the more time you will have to catch up.
nony is offline   Quick reply to this message.
Old 10-16-2005, 05:55 PM   #17
Bryan Mailloux
RCC Master Contributor
Bryan Mailloux's Avatar
I am: Bryan M
Join Date: Oct 2003
Location: Norwich

Feedback: 3 / 100%
Posts: 1,387
Total Props: 1

Tisk Tisk Bryan pipes are not allowed in combat, bad boy
Well Ya know I have to try something faster. Right now it won't even keep the streamer on. Just to play around and raise some eyebrows at the field.
Bryan Mailloux is offline   Quick reply to this message.
Closed Thread

Quick Reply

Register Now

In order to be able to post messages on the RCCanada - Canada Radio Controlled Hobby Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

Member names may only be composed of alpha-numeric characters. (A-Z and 0-9)

!!ATTENTION ADVERTISERS!! If you intend on advertising anything on this forum, whatsoever, you are required to first contact us here . Additionally, we do NOT allow BUSINESS NAMES unless you are an Authorized Vendor. If you own a business, and want to do sales on this site via posting or private message, you will need to follow the rules. Shops, Stores, Distributors, Group Buys without being authorized will see your account terminated.
User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.
Confirm Password:
Email Address
Please enter a valid email address for yourself.
Email Address:
Your Name
Your first name and last initial is required if you plan on using the forum.
Which city & province you live in. This is mandatory for classified listings.
Radio of choice?
Which radio is your current favorite to use?
Number of RC Vehicles?
How many boats, cars, planes do you own?


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
vBulletin Message

Thread Tools
Display Modes

Forum Jump

All times are GMT -5. The time now is 05:06 PM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2016 DragonByte Technologies Ltd.