C3 Tech/Performance V8 Technical Info, Internal Engine, External Engine, Basic Tech and Maintenance for the C3 Corvette

Purpose of 2.5" sleeve to downpipes?

 
Old 11-02-2018, 12:33 PM
  #1  
carriljc
CF Senior Member
Thread Starter
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 2,412
Liked 206 Times in 194 Posts
Default Purpose of 2.5" sleeve to downpipes?

I have Ramhorns with 2.5" outlets, and 64-65 2.5" downpipes....

Do I have to use the 2.5" sleeve shown in the images below? (Between the donut and the downpipe?) I'm going to go check to see how it bolts up without it, but I thought I'd ask also.....

https://www.corvettecentral.com/c3-6...c2%26count%3d9



Last edited by carriljc; 11-02-2018 at 12:34 PM.
carriljc is offline  
Old 11-02-2018, 01:05 PM
  #2  
Willcox Corvette
Premium Supporting Vendor
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 64,934
Liked 1,360 Times in 1,141 Posts
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Default

The purpose of the insert "sleeve" was to prevent you from burning the packing out... Always use them! It will bolt up fine without it, but it acts as a barrier between the hot exhaust and the packing.

Ernie

Last edited by Willcox Corvette; 11-02-2018 at 01:06 PM.
Willcox Corvette is offline  
The following users liked this post: Willcox Corvette
carriljc (11-02-2018)
Old 11-03-2018, 09:24 AM
  #3  
scura283
Junior Member
 
scura283's Avatar
 
Member Since: Oct 2004
Posts: 46
Liked 19 Times in 12 Posts
Default

Look here:
https://www.castheads.com/manifolds-...pes-pipe-kits/
One of these kits could be adapted to eliminate the packing and sleeve
Not cheap, but you would have a true 2 1/2" exhaust.
scura283 is offline  
Old 11-03-2018, 01:17 PM
  #4  
Priya
CF Senior Member
 
Priya's Avatar
 
Member Since: Dec 2009
Location: Saskatoon Saskatchewan
Posts: 5,588
Liked 262 Times in 231 Posts
Default

Originally Posted by Willcox Corvette View Post
The purpose of the insert "sleeve" was to prevent you from burning the packing out... Always use them! It will bolt up fine without it, but it acts as a barrier between the hot exhaust and the packing.
Ernie
What's this packing of which you so boldly speak?
Priya is offline  
Old 11-03-2018, 01:47 PM
  #5  
Willcox Corvette
Premium Supporting Vendor
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 64,934
Liked 1,360 Times in 1,141 Posts
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Default

Originally Posted by Priya View Post
What's this packing of which you so boldly speak?
The packing is the insulator between the pipe and the manifold. Everyone has it... what they don't realize is that the packing will last you way longer with the insert in there, either 2" or 2.5. I'm not sure where they got the name of "donut gasket", GM always called in a packing.

Willcox



Willcox Corvette is offline  
The following users liked this post: Willcox Corvette
Priya (11-03-2018)
Old 11-03-2018, 02:18 PM
  #6  
Priya
CF Senior Member
 
Priya's Avatar
 
Member Since: Dec 2009
Location: Saskatoon Saskatchewan
Posts: 5,588
Liked 262 Times in 231 Posts
Default

Thanks
Priya is offline  
Old 11-04-2018, 09:11 AM
  #7  
resdoggie
1976 Blue-Green L-82 4-sp
Support Corvetteforum!
 
resdoggie's Avatar
 
Member Since: Mar 2011
Location: Some days your the dog and some days your the hydrant.
Posts: 3,044
Liked 335 Times in 305 Posts
Default

Because it looks somewhat like a donut?
resdoggie is offline  
The following users liked this post: resdoggie
20mercury (11-04-2018)
Old 11-04-2018, 12:30 PM
  #8  
carriljc
CF Senior Member
Thread Starter
 
carriljc's Avatar
 
Member Since: Jan 2001
Posts: 2,412
Liked 206 Times in 194 Posts
Default

Thanks for the info. Guess I'll use the sleeves..... good thing I've learned to ask around here instead of just ASSuming things.

I like the "Donut" gasket term.... communicates the information and provides a visual description in your mind.

So far it looks like those 2.5" 64-65 downpipes are going to fit quite well into my 68.
carriljc is offline  
Old 11-04-2018, 03:13 PM
  #9  
Priya
CF Senior Member
 
Priya's Avatar
 
Member Since: Dec 2009
Location: Saskatoon Saskatchewan
Posts: 5,588
Liked 262 Times in 231 Posts
Default

Originally Posted by carriljc View Post

I like the "Donut" gasket term.... communicates the information and provides a visual description in your mind.
Yes, I think its the better term for allowing people to figure out what it means from context.

Priya is offline  
Old 11-04-2018, 04:11 PM
  #10  
Willcox Corvette
Premium Supporting Vendor
 
Willcox Corvette's Avatar
 
Member Since: Aug 2006
Location: Jeffersonville Indiana 812-288-7103
Posts: 64,934
Liked 1,360 Times in 1,141 Posts
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Default

Originally Posted by resdoggie View Post
Because it looks somewhat like a donut?
I don't eat donuts... lol
Willcox Corvette is offline  
The following users liked this post: Willcox Corvette
resdoggie (11-05-2018)
 


Thread Tools
Search this Thread
Quick Reply: Purpose of 2.5" sleeve to downpipes?


Sponsored Ads
Vendor Directory

Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: