1 3/4 headers
Thread Starter
Racer
Joined: Mar 2007
Posts: 337
Likes: 1
From: dallas texas
1 3/4 headers
So when i built my 383 (gen I block) , i used straight plug heads. realizing too late that its next to impossible to find a set of 1 3/4 headers for straight plug heads that will fit my vette. i used a cheap set of 1 5/8 to break the motor in, i am still in need of a set of headers that will work. Has anybody seen any 1 3/4 or know where i can get them? this is the only thing holding me back from finishing my car. 
Race Director
Joined: Nov 2003
Posts: 12,221
Likes: 446
From: Overland Park Kansas
2020 Corvette of the Year Finalist (appearance mods)
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Also, TPIS, Hooker, Stainless Works, and Melrose are worth contacting. EM, TPIS, and Hooker make 1 3/4" for vette. Who know about fitment with straight plugs....Reps at all the companies can say if they think they'll fit. Or,,, one or two of those companies MIGHT be able to custom make a set.
How do you fell about installing platinum plugs, then r/r the headers when you need to change them?!?!
How do you fell about installing platinum plugs, then r/r the headers when you need to change them?!?!
Thread Starter
Racer
Joined: Mar 2007
Posts: 337
Likes: 1
From: dallas texas
well the engine will make about 500 hp. are you saying that 1 3/4 will actually be too much? 383's love to breathe so i figured 1 5/8 would be restrictive
Last edited by texasedirpvette'91; Jul 25, 2010 at 11:03 PM.
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
I disagree, but to each their own. On my 383, I made gains with 1 3/4 over 1 5/8" I had heads flowing ~285cfm so that may be part of it. But it sure as heck wasn't at 7k. I also had 0 losses.
As for the back pressure argument...
"Literally. If you have ever heard that an engine needs a little backpressure, you might want to ask yourself why an engine would want an exhaust system that literally pushes exhaust back into the combustion chamber rather than sucking it out. The simple answer is, it doesn't. "
http://www.popularhotrodding.com/tec...ics/index.html
The only reason for smaller tube headers being scavenging and I just don't believe that a mild 383 can't take advantage of 1 3/4", based on solely my experience.
Le Mans Master
Joined: Jul 2007
Posts: 5,043
Likes: 8
From: Tampa Florida
Would "shorty" style plugs work with the bigger tubes in place?
Example:
http://www.jcwhitney.com/shorty-silv...uestid=1173398
Example:
http://www.jcwhitney.com/shorty-silv...uestid=1173398
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On a 383, I would definitely run 1.75" headers. EM, TPiS, Hooker, etc. Only thing I would call and ask about is fitment with the plug angle.
TPiS I know works with the straight plug, and I thought Hooker made some (at one time) with a straight plug angle. I would expect to possibly burn up some plug wires though, depending on how well the fitment works out. You may not find a perfect fit.
TPiS I know works with the straight plug, and I thought Hooker made some (at one time) with a straight plug angle. I would expect to possibly burn up some plug wires though, depending on how well the fitment works out. You may not find a perfect fit.
Thread Starter
Racer
Joined: Mar 2007
Posts: 337
Likes: 1
From: dallas texas
I disagree, but to each their own. On my 383, I made gains with 1 3/4 over 1 5/8" I had heads flowing ~285cfm so that may be part of it. But it sure as heck wasn't at 7k. I also had 0 losses.
As for the back pressure argument...
"Literally. If you have ever heard that an engine needs a little backpressure, you might want to ask yourself why an engine would want an exhaust system that literally pushes exhaust back into the combustion chamber rather than sucking it out. The simple answer is, it doesn't. "
http://www.popularhotrodding.com/tec...ics/index.html
The only reason for smaller tube headers being scavenging and I just don't believe that a mild 383 can't take advantage of 1 3/4", based on solely my experience.
As for the back pressure argument...
"Literally. If you have ever heard that an engine needs a little backpressure, you might want to ask yourself why an engine would want an exhaust system that literally pushes exhaust back into the combustion chamber rather than sucking it out. The simple answer is, it doesn't. "
http://www.popularhotrodding.com/tec...ics/index.html
The only reason for smaller tube headers being scavenging and I just don't believe that a mild 383 can't take advantage of 1 3/4", based on solely my experience.
Would "shorty" style plugs work with the bigger tubes in place?
Example:
http://www.jcwhitney.com/shorty-silv...uestid=1173398
Example:
http://www.jcwhitney.com/shorty-silv...uestid=1173398
you got a part number? i would call like vader says to do, but im army, and work from 0530 to 1800 everyday. kinda hard to find time to make a phone call during work hours.
Last edited by texasedirpvette'91; Jul 27, 2010 at 01:07 AM.
