C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine

Long Tube Header dimensions

Thread Tools
 
Search this Thread
 
Old Jan 10, 2007 | 06:37 PM
  #1  
c4cruiser's Avatar
c4cruiser
Thread Starter
Team Owner
20 Year Member
Veteran: Army
 
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Default Long Tube Header dimensions

I'm thinking about a set of Heddman Elites for my 87 and I want to install a true dual exhaust system. At the same time, I want to install a pair of aftermarket universal hi-flow cats to help with emissions.

Although I do not have to have the car smog tested where I live, if I were ever to sell the car to somebody that lives in an area where a sniffer test is required, I would like the car to be able to at least come close to lower emissions (and it's good for the air too )

Most of the small aftermarket cats I have seen are about 11 to 14 inches long so my question is how far back do the Heddman headers extend beyond the end of the block face? Will there be enough room to add some cats before the pipes have to turn inward behind the tranny?

The car is a 4+3 and I'm also curious if there is enough room on the shift linkage side of the tranny to do this.
Reply
Old Jan 10, 2007 | 07:09 PM
  #2  
rel3rd's Avatar
rel3rd
Burning Brakes
15 Year Member
 
Joined: Jun 2006
Posts: 1,096
Likes: 28
From: Baltimore MD
Default

Here's Hedman Elites with a stock Y pipe on a 4+3 car...I haven't installed mine yet, so I can give a definitive answer, but here is a good pic to give you an idea...

Reply
Old Jan 13, 2007 | 02:27 PM
  #3  
c4cruiser's Avatar
c4cruiser
Thread Starter
Team Owner
20 Year Member
Veteran: Army
 
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
Default

That's a neat view from the back side. But it look like there would be no way to install small cats where the pre-cats were originally placed. From what I see there, the collectors come back to about where the trans attaches to the bellhousing.

But if I go with small cats with a 3" pipe, they might be able to attach directly to the reducer and run the new exhaust pipe back from there.
Reply
Old Jan 13, 2007 | 03:31 PM
  #4  
Corvette Kid's Avatar
Corvette Kid
Large Impressive Member
Supporting Lifetime Gold
20 Year Member
Liked
Loved
Community Favorite
 
Joined: Jul 2003
Posts: 65,811
Likes: 71
From: Good health is merely the slowest possible rate at which one can die
St. Jude Donor '04-'05-'06-'07
Default

Originally Posted by c4cruiser

But if I go with small cats with a 3" pipe, they might be able to attach directly to the reducer and run the new exhaust pipe back from there.
You should have no problem doing that. Actually, I don't think the Hedmans come back as far as some of the other C4 headers. But with any of the commonly available C4 headers the cats are routinely placed just beyond the header collector. It can get a little tricky on automatics sometimes but I have R/T cats right off of my SW headers with a 4L60E transmission. If you'd like I can get you a length measurement on the R/Ts. And good for you for caring enough to install cats. I think that's important for the obvious reasons. Plus, we don't want to give the radical tree-huggers any more fodder for their desire to destroy our hobby and even completely eliminate the internal combustion engine in their perfect little (and twisted) utopias.
Reply
Old Jan 13, 2007 | 06:00 PM
  #5  
Ruff Rider's Avatar
Ruff Rider
Racer
 
Joined: Sep 2005
Posts: 484
Likes: 0
From: Redwood City CA
Default

Originally Posted by Corvette Kid
good for you for caring enough to install cats. I think that's important for the obvious reasons. Plus, we don't want to give the radical tree-huggers any more fodder for their desire to destroy our hobby and even completely eliminate the internal combustion engine in their perfect little (and twisted) utopias.
Reply

Get notified of new replies

To Long Tube Header dimensions





All times are GMT -4. The time now is 01:04 AM.

story-0
10 Ugly Corvettes That We Still Kinda Love

Slideshow: 10 ugly Corvettes that we still kinda love.

By Joe Kucinski | 2026-06-03 10:34:17


VIEW MORE
story-1
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer

A lot of money has changed hands at the online auction house over the years.

By Brett Foote | 2026-06-03 10:21:50


VIEW MORE
story-2
10 Things Every Corvette Owner Needs (2026 Edition)

Slideshow: 10 great gifts Corvette enthusiasts actually want for Father's Day!

By Michael S. Palmer | 2026-06-03 15:43:40


VIEW MORE
story-3
8 Most "Only Corvette Owners Understand" Quirks and Problems

Slideshow: These are the quirks, annoyances, and oddly lovable problems that every Corvette owner eventually learns to live with.

By Pouria Savadkouei | 2026-05-28 09:31:39


VIEW MORE
story-4
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years

Slideshow: 10 reasons why the C6 Z06 is still a performance benchmark after 20 years.

By Joe Kucinski | 2026-05-27 17:20:09


VIEW MORE
story-5
How Much Horsepower Every Corvette Engine "LOST" in 1972

Slideshow: How much horsepower every Corvette engine lost in 1972.

By Joe Kucinski | 2026-05-27 16:54:53


VIEW MORE
story-6
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!

Slideshow: How to Protect A Convertible Top: 10 DOs & DON'Ts

By Michael S. Palmer | 2026-04-03 00:00:00


VIEW MORE
story-7
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!

Slideshow: The 10 most explosive Corvettes ever built based on power-to-weight ratio.

By Joe Kucinski | 2026-05-20 07:23:03


VIEW MORE
story-8
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter

Slideshow: From C1 to C8 we compare every Corvette generation by the numbers.

By Joe Kucinski | 2026-05-12 16:54:12


VIEW MORE
story-9
8 Coolest Corvette Pace Cars (and Replicas) of All Time

Slideshow: Some Corvette pace cars became collectible legends, while others perfectly captured the look and attitude of their era.

By Verdad Gallardo | 2026-05-11 09:50:51


VIEW MORE