Long tube header install problems
Thread Starter
Intermediate
Joined: Sep 2022
Posts: 37
Likes: 15
From: Lake Havasu City, Arizona
Long tube header install problems
I’m putting a set of long tube Hedman Hedders (part# 68308) and a Pypes true dual 2 1/2” exhaust on my 1982 Corvette with the engine in the car. I am also deleting the cat and air injection pump with all the plumbing in the process. I need some advice from someone who has done this install. First off disassembling the stock exhaust was a real PIA! Getting all those heat shields off just about killed me. I have the drivers side installed, thinking it would be the harder, NOT! My questions are:
1. What did you do about plug wires? Looks like the forward-most and rear-most plug wires can be routed under like stock but the center two on both sides will need to be routed from above.
2. Dip stick tube - I cannot get the headers up over it and they won’t drop in from the top. What have others done to solve this problem?
3. Center exhaust pipe hangers. I can adapt the stock hanger that was in front of the cat, but what have others done about the one behind the cat where the new system has two pipes instead of the one large merged pipe.
Thanking everyone who has taken the time to read my post and respond with suggestions.
1. What did you do about plug wires? Looks like the forward-most and rear-most plug wires can be routed under like stock but the center two on both sides will need to be routed from above.
2. Dip stick tube - I cannot get the headers up over it and they won’t drop in from the top. What have others done to solve this problem?
3. Center exhaust pipe hangers. I can adapt the stock hanger that was in front of the cat, but what have others done about the one behind the cat where the new system has two pipes instead of the one large merged pipe.
Thanking everyone who has taken the time to read my post and respond with suggestions.
Burning Brakes
Joined: Mar 2013
Posts: 750
Likes: 180
From: Springfield Missouri
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,149
Likes: 9,279
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I cut the piece that goes across the flange so that the headers looked like they had 3 seperate manifold mounting points instead of the long bar.....never liked that look
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,149
Likes: 9,279
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
2.5 would be perfect. 3 if you were pushing real power. Smaller exhaust is just a cork on your Engine. If you cant get it to exhale, it cannot inhale
2.5 leaves you a small amount of room to grow
2.5 leaves you a small amount of room to grow
Melting Slicks
Joined: May 2021
Posts: 2,263
Likes: 1,308
From: Fleming Island, FL
Every exhaust system sizing chart says differently. And every book I've read on exhaust all says going too big will cause loss of power. So who knows? But I know this much, My headers plumbed into my stock y pipe gave me two tenths of a second in the quarter. Then I built my own y pipe consisting of two and a half inch mandrel Bend tubing and loss two tenths in the quarter. Yet back pressure drop from 3.25 to 2 PSI. So pipe diameter versus exhaust gas velocity, I guess I'll go with exhaust gas velocity.
Le Mans Master
Joined: May 2002
Posts: 5,086
Likes: 786
From: Lebanon Township New Jersey
Every exhaust system sizing chart says differently. And every book I've read on exhaust all says going too big will cause loss of power. So who knows? But I know this much, My headers plumbed into my stock y pipe gave me two tenths of a second in the quarter. Then I built my own y pipe consisting of two and a half inch mandrel Bend tubing and loss two tenths in the quarter. Yet back pressure drop from 3.25 to 2 PSI. So pipe diameter versus exhaust gas velocity, I guess I'll go with exhaust gas velocity.
You can go to dragtimes.com and look up DA for any time of day on any track on any date.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,149
Likes: 9,279
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
YA because going open headers in all dyno tests alwasy presents a power loss......
Thread Starter
Intermediate
Joined: Sep 2022
Posts: 37
Likes: 15
From: Lake Havasu City, Arizona
I appreciate the help, but aren't we getting a little off subject? The plug wires were the least of my worries. I will pull off the starter and get the dip stick tub out. Has anyone installed the Pypes true duals on a 1980-1982 with long tube headers? Looking for installation photos and suggestions for the middle hanger.
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,149
Likes: 9,279
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
they always dooo
Melting Slicks
Joined: May 2021
Posts: 2,263
Likes: 1,308
From: Fleming Island, FL
Just to let you know, you misspelled "always"
Race Director
Joined: Jan 2002
Posts: 11,614
Likes: 347
From: No Where USA
I appreciate the help, but aren't we getting a little off subject? The plug wires were the least of my worries. I will pull off the starter and get the dip stick tub out. Has anyone installed the Pypes true duals on a 1980-1982 with long tube headers? Looking for installation photos and suggestions for the middle hanger.
You might need to change the crossmember. Unless both pipes go to the passenger side.