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

78 exhaust question

Thread Tools
 
Search this Thread
 
Old Feb 20, 2005 | 10:03 AM
  #1  
gh78's Avatar
gh78
Thread Starter
Instructor
 
Joined: Jan 2004
Posts: 242
Likes: 0
From: Manchester Mi
Default 78 exhaust question

since I am having my car re-built due to an accident last fall, I decided to have true dual exhaust installed (less the cat) 2 1/2 in. Dyna-flow mufflers. Do I need an H pipe or run them both back seperate to mufflers?
Thanks
Reply
Old Feb 20, 2005 | 10:14 AM
  #2  
soxx35's Avatar
soxx35
Advanced
15 Year Member
 
Joined: Nov 2003
Posts: 86
Likes: 0
From: RI
Default

either or would work fine with the h pipe you will get alittle more low end power. Also it will smooth out the exhust tone and quiet it down alittle. In my opinion also if you have a stock engine and are not going to do any major mods i would go with the 2 1/4 inch exhust instead. the 2 1.2 might flow too well.
rj
Reply
Old Feb 20, 2005 | 11:42 AM
  #3  
C3Muscle352's Avatar
C3Muscle352
Advanced
 
Joined: Feb 2005
Posts: 79
Likes: 0
Default

i have a '78 and opened it up to a true dual, i got about 30hp increase, and it was noticibly faster. I dont have an h-pipe althought people have reccomended that i either make or buy one because it gives you more horses/torque in the lower rpm. So if you had the option to do it now, i would go with the H-pipe.
Reply
Old Feb 20, 2005 | 11:53 AM
  #4  
gh78's Avatar
gh78
Thread Starter
Instructor
 
Joined: Jan 2004
Posts: 242
Likes: 0
From: Manchester Mi
Default

Thanks! I'll talk to the shop tmorrow about including the H pipe
Reply
Old Feb 20, 2005 | 12:26 PM
  #5  
mvftw's Avatar
mvftw
Melting Slicks
20 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Feb 2003
Posts: 2,330
Likes: 6
From: Long Island NY
Default

I have a stock L82 and went with true duals 2 1/4" H-pipe and Flowmaster 50's . 2 1/4" is better then 2 1/2" for a stock motor...
Reply
Old Feb 20, 2005 | 02:48 PM
  #6  
C3Muscle352's Avatar
C3Muscle352
Advanced
 
Joined: Feb 2005
Posts: 79
Likes: 0
Default

i thought the stock size was 2.25 ? i went 2.5 because 3 would just be too big. What kind of performance increade did you get mvftw ? my esp fly hp is 224 from the stock 185 and the exhaust is all i have done.
Reply
Old Feb 20, 2005 | 02:54 PM
  #7  
gh78's Avatar
gh78
Thread Starter
Instructor
 
Joined: Jan 2004
Posts: 242
Likes: 0
From: Manchester Mi
Default

we went with inlet size on muffles which was 2.5 but what is odd is that outlet is 2.25
Reply
Old Feb 20, 2005 | 06:19 PM
  #8  
DRKCYDE's Avatar
DRKCYDE
Drifting
15 Year Member
 
Joined: Nov 2004
Posts: 1,711
Likes: 7
From: Metro Detroit -- Farmington Hills MI
Cruise-In VII & IX Veteran
Default

I would love to know how much that is going to cost you. I am thinking of getting the same setup.
Reply
Corvette Stories

The Best of Corvette for Corvette Enthusiasts

story-0

Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

 Michael S. Palmer
story-1

10 Revolutionary 'Corvette Firsts' Most People Don't Know

 Joe Kucinski
story-2

5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

 Michael S. Palmer
story-3

2027 Corvette vs The World: Every C8 vs Its Closest Competitor

 Joe Kucinski
story-4

10 Most Common Corvette Problems of the Last 20 Years!

 Joe Kucinski
story-5

5 MOST and 5 LEAST Popular Corvette Model Years in History!

 Joe Kucinski
story-6

2027 Corvette Buyer's Guide: Everything You Need to Know!

 Joe Kucinski
story-7

10 Things C8 Corvette Owners Hate (But Won't Tell You)

 Joe Kucinski
story-8

10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

 Brett Foote
story-9

Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

 Joe Kucinski
Old Feb 21, 2005 | 10:19 AM
  #9  
mvftw's Avatar
mvftw
Melting Slicks
20 Year Member
Conversation Starter
All Eyes On Me
 
Joined: Feb 2003
Posts: 2,330
Likes: 6
From: Long Island NY
Default

Stock was 2 1/4" but that was with a 'Y' pipe, when you go to true duals you are adding about 6' of pipe, thats the difference...that's why 2 1/4" is better for close to stock engines...
Reply
Old Feb 21, 2005 | 12:41 PM
  #10  
C3Muscle352's Avatar
C3Muscle352
Advanced
 
Joined: Feb 2005
Posts: 79
Likes: 0
Default

why would longer pipe be better? i was thinking about just runing dumps off my headers.
Reply
Old Feb 21, 2005 | 01:23 PM
  #11  
den(thevetteman)78's Avatar
den(thevetteman)78
Pro
20 Year Member
Conversation Starter
All Eyes On Me
 
Joined: May 2004
Posts: 712
Likes: 4
From: caraquet N.B Canada
Default

That's what i have on my '78 L82, 2½" pipe with no cat and '80's dyno- max muflers.The '80's muflers are smaller and less restrective than the big round muflers. The sound is better. This year i bought a set of headers that i will put on this spring.
Reply
Old Feb 21, 2005 | 02:05 PM
  #12  
C3Muscle352's Avatar
C3Muscle352
Advanced
 
Joined: Feb 2005
Posts: 79
Likes: 0
Default

Originally Posted by den(thevetteman)78
That's what i have on my '78 L82, 2½" pipe with no cat and '80's dyno- max muflers.The '80's muflers are smaller and less restrective than the big round muflers. The sound is better. This year i bought a set of headers that i will put on this spring.

i did that exact setup except that i used 60s i think. I also got some chrome ceramic headers that im putting on in the next few days, along with changing out my motor mounts from fubber to urathane.
Reply

Get notified of new replies

To 78 exhaust question





All times are GMT -4. The time now is 01:09 AM.

story-0
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!

Slideshow: the top 10 things Corvette owners want in the C9 Corvette

By Michael S. Palmer | 2026-04-30 12:41:15


VIEW MORE
story-1
10 Revolutionary 'Corvette Firsts' Most People Don't Know

Slideshow: 10 Important Corvette 'firsts' that every fan should know.

By Joe Kucinski | 2026-04-29 17:02:16


VIEW MORE
story-2
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2

Slideshow: Should you buy a 2020-2026 Corvette or wait for 2027?

By Michael S. Palmer | 2026-04-22 10:08:58


VIEW MORE
story-3
2027 Corvette vs The World: Every C8 vs Its Closest Competitor

Slideshow: 2027 Corvette lineup vs the world.

By Joe Kucinski | 2026-04-24 16:12:42


VIEW MORE
story-4
10 Most Common Corvette Problems of the Last 20 Years!

Slideshow: 10 major Corvette problems from the last 20 years.

By Joe Kucinski | 2026-04-14 16:37:05


VIEW MORE
story-5
5 MOST and 5 LEAST Popular Corvette Model Years in History!

Slideshow: 5 most and least popular Corvette model years.

By Joe Kucinski | 2026-04-08 13:25:01


VIEW MORE
story-6
2027 Corvette Buyer's Guide: Everything You Need to Know!

Slideshow: 2027 Corvette buyer's guide

By Joe Kucinski | 2026-04-17 16:41:08


VIEW MORE
story-7
10 Things C8 Corvette Owners Hate (But Won't Tell You)

Slideshow: 10 things C8 Corvette owners hate, but won't tell you.

By Joe Kucinski | 2026-04-01 18:36:07


VIEW MORE
story-8
10 Best Corvettes Coming to Barrett-Jackson Palm Beach 2026!

Slideshow: Should you add one of these incredible Corvettes to your garage?

By Brett Foote | 2026-04-01 18:14:05


VIEW MORE
story-9
Every Corvette Grand Sport Explained! (C2, C4, C6, C7, & C8)

Slideshow: Every Corvette Grand Sport explained

By Joe Kucinski | 2026-03-26 07:13:44


VIEW MORE