GT40s.com
MK-I  MK-II  MK-III  MK-IV  GULF  MIRAGE  J-CAR  LOLA
GT40s.com
Home Forum Gallery Support GT40s.com  
Register FAQ Advertisers Search Today's Posts Mark Forums Read

Go Back   GT40s.com > >

Notices

GT40 Tech - Engines/Induction/Exhaust Motors and engine related - right here!

Reply
 
Thread Tools Display Modes
Old 29th April 2018, 10:19 PM   #1
Kim Haun
Rookie
United States
 
Join Date: Feb 2018
Location: Los Angeles
GT40: RCR GT40
Posts: 29
Flange Choice for Exhaust Build

So I'm in the process of building my bundle of snakes. I borrowed a friends Iceengine header design kit and am working away. I was trying to put everything together with one piece header flanges on each side but for a number of reasons I would like to cut the flange into individual pieces for each port. Does anyone know of a big down-side to going this way? The engine is a Ford 363 Windsor and the heads have the 3" bolt spacing. The flange will be 3/8" thick.

Kim
Kim Haun is offline   Reply With Quote
Old 30th April 2018, 09:08 PM   #2
Big-Foot's Avatar
Big-Foot
Administrator
United States
 
Join Date: Jan 2007
Location: Kenyon, MN
GT40: Gulf Cart
Posts: 6,731
Re: Flange Choice for Exhaust Build

There’s no down-side that I’m aware of.
As a matter of fact, I think that the seal of the flanges would be better that way.
__________________
Regards - Randy
-- Youth and talent are no match for old age and treachery!
GT40 RCR40 #45 G50-331-Weber IDAs ((Sold))
My build site:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Big-Foot is online now   Reply With Quote
Old 11th May 2018, 10:42 AM   #3
bill kearley
A Tenth
Canada
 
Join Date: Jan 2008
Location: Canada
GT40: CAV 193
Posts: 126
Re: Flange Choice for Exhaust Build

On a 40 you must have a flange for each pipe, I wish I had 3 inch heads, room for a a 2in. exhaust and looks great. keep an eye on clam fit over pipes.
bill kearley is offline   Reply With Quote
Old 13th May 2018, 03:20 AM   #4
A Tenth
United Kingdom
 
Join Date: Apr 2005
Location: Essex UK
GT40: RCR
Posts: 108
Re: Flange Choice for Exhaust Build

My 302 V8 exhaust has a single one piece flange either side and it works fine. The only minor issue is clearance to get a couple of the socket head bolts in. I had to thin down a couple of the bolt heads. The exhaust has been on and off a couple of times and once after running the engine and everything continued to line up and seal against the gasket. Importantly, from a visual point of view, the two pipes continued to exit dead central through the rear body aperture. I’d be concerned that without ‘anchoring’ the pipes to a single flange you will have assembly and alignment issues.
Just my 5 penny worth!
Cheers
Roger Allen
Roger Allen is offline   Reply With Quote
Old 13th May 2018, 04:52 AM   #5
Udo
Fivepointseven's Avatar
Fivepointseven
Rookie
Germany
 
Join Date: Feb 2012
Location: Germany
GT40: KVA/SGT
Posts: 64
Re: Flange Choice for Exhaust Build

Kim, a brand new lessons learned from my exhaust build: try to build as low as possible in order to keep as much distance as possible to the rear clip. I used single flanges also, which also makes the build much easier.
__________________
GD MK IV, 1965 Beetle, KVA/SGT under construction
Fivepointseven is offline   Reply With Quote
Old 13th May 2018, 06:06 PM   #6
Cliffbeer2
I Have No Life
United States
 
Join Date: Jun 2007
Location: Sand Point, WA
GT40: CAV - sold.....
Posts: 2,676
Re: Flange Choice for Exhaust Build

Kim, the separate flanges should be fine, have done it that way myself. One recommendation, use flanges that are as thick as possible. Think I may have used 3/8th last time I made a custom manifold. 1/4 might be OK but in my experience thicker is better. You might be surprised how much a flange face will flex/curve under point loading.

Related, I've found that crushed copper gaskets work best for individual flanges. Just my $.02.
Cliffbeer2 is offline   Reply With Quote
Old 15th May 2018, 01:04 AM   #7
bill kearley
A Tenth
Canada
 
Join Date: Jan 2008
Location: Canada
GT40: CAV 193
Posts: 126
Re: Flange Choice for Exhaust Build

Was it fun fitting with the crossover pipes?
bill kearley is offline   Reply With Quote
Old 15th May 2018, 09:48 AM   #8
mbrooks
A Tenth
United States
 
Join Date: May 2008
Location: kansas, usa
Posts: 162
Re: Flange Choice for Exhaust Build

Use the one piece flange, set everything up and weld, then split the flange would be my process. 4 into 2 into 1 with the 1 being a very large muffler with 6" inlet/outlet and straight through if you could fit it. That will sound awesome and be surprisingly quieter then you imagine.
mbrooks is offline   Reply With Quote
Old 19th May 2018, 12:38 AM   #9
Kim Haun
Rookie
United States
 
Join Date: Feb 2018
Location: Los Angeles
GT40: RCR GT40
Posts: 29
Re: Flange Choice for Exhaust Build

Thanks for the input everyone! I finished the exhaust. Turned out great! All primaries are within an inch in length of each other and I was able to use one piece flanges. It sits as low as it possibly can. I'll be building heat shields for the transaxle and rear of the intake. The pipes will be eventually wrapped in titanium wrap. Best of all, every spark plug can be changed blindfolded, they are that easy to access! I used the Iceengine design kit and then cut and tacked it all together, built a jig and had Manuel at JMD Tubes TIG weld everything.

Flange Choice for Exhaust Build-img_2914-jpgFlange Choice for Exhaust Build-img_2967-jpgFlange Choice for Exhaust Build-img_2979-jpg
Kim Haun is offline   Reply With Quote
Old 19th May 2018, 08:01 PM   #10
70gsconvt
A Tenth
United States
 
Join Date: Jul 2017
Location: Cleveland Ohio
GT40: I wish
Posts: 127
Re: Flange Choice for Exhaust Build

Looks awesome. Can you have someone make a template of the thing for others to duplicate?
70gsconvt is online now   Reply With Quote
Old 21st May 2018, 01:49 AM   #11
Kim Haun
Rookie
United States
 
Join Date: Feb 2018
Location: Los Angeles
GT40: RCR GT40
Posts: 29
Re: Flange Choice for Exhaust Build

Quote:
Originally Posted by 70gsconvt View Post
Looks awesome. Can you have someone make a template of the thing for others to duplicate?

There are so many variables to each build I doubt this exhaust would fit other applications. Where the motor sits and the angle, the port height on the heads etc...along with different clearances for transaxles would make it impossible to successfully duplicate and fit. I now know why Fran only makes exhaust systems custom for each vehicle.

Kim
Kim Haun is offline   Reply With Quote
Reply

Tags
3/8, big, flange, header, port


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Display Modes

 
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 On

Forum Jump


All times are GMT -4. The time now is 09:48 PM.