And I think the other size headers you have are 1 7/8" instead of 1 5/8".
LT Header Question
Thread Starter
Burning Brakes
Joined: Dec 2015
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From: Houston Tx
LT Header Question
So I think I already know the answer to my question but I want a second opinion or maybe 3. I have an 03Z that is stock with the exception of a Haltech intake.. I have 2 sets of ARH headers for it. 1 5/8 non-smog and 1 3/4 smog. The X is catted. Which set do the corvette gods suggest. I'm thinking the 1 3/4 for the cam I plan to do but I'm worried it might be to large of a primary.
FYI, I will be ordering a Vindicator cam and supporting mods next week and all parts will go on at the sametime then followed up by tuning.
Thanks in advance and any help is appreciated.
FYI, I will be ordering a Vindicator cam and supporting mods next week and all parts will go on at the sametime then followed up by tuning.
Thanks in advance and any help is appreciated.
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if they are in fact 1 7/8 and not 1 5/8 I would use those, no air pipe provisions will look cleaner and by removing the air pump and pipes it makes plug changes easier as well... either one should make good power regardless though
Team Owner
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From: At the beach in little Rhody
Personally, I would go with the largest primary and then have a custom exhaust shop remove the AIR connection. Remove the AIR piping and check valves, which are a source of problems, and tune it out.
I didn't think ARH ever made a 1-5/8" primary for the C5.
I didn't think ARH ever made a 1-5/8" primary for the C5.
Last edited by vettenuts; Aug 25, 2016 at 07:15 AM.
Thread Starter
Burning Brakes
Joined: Dec 2015
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From: Houston Tx
Here is the original ad I purchased the "1 5/8" headers from back in January. They were advertised as 1 3/4. I didnt even bother to measure until I received the other set last night when I noticed the size difference. Maybe I've done this wrong but I always thought primaries were advertised and measured by ID. I measured the OD of both sets and come up with 1 3/4 and 1 7/8.
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Here is the original ad I purchased the "1 5/8" headers from back in January. They were advertised as 1 3/4. I didnt even bother to measure until I received the other set last night when I noticed the size difference. Maybe I've done this wrong but I always thought primaries were advertised and measured by ID. I measured the OD of both sets and come up with 1 3/4 and 1 7/8.
https://www.corvetteforum.com/forums...-for-sale.html
https://www.corvetteforum.com/forums...-for-sale.html
Thread Starter
Burning Brakes
Joined: Dec 2015
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From: Houston Tx
Other than the cam swamp I do not plan on any other mods. I dont race the car just my weekend cruiser. Ill be selling the set of headers not being used. I mainly bought the second set because I needed the X pipe. X pipe new from ARH was 600+.
Racer
Joined: Nov 2014
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From: Forest Hills, New York
The 1 ¾ would be my personal suggestion. Gives you room to grow and there are no down sides to do them now on a stock engine. The 1 7/8 given what you have done, and planning to do with a mild cam you would loose to much low and mid range torque with.
Last edited by RomanNYC; Aug 25, 2016 at 10:17 AM.
Team Owner
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From: At the beach in little Rhody
Go with the larger primary. I have yet to see a curve where mid range is sacrificed with the 1-7/8 primary. Since they are off-road, the AIR system can be eliminated as well.
Racer
Joined: Nov 2014
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From: Forest Hills, New York
could be true with other manufacture headers, i know that when comparing the LG 1 3/4 vs LG 1 7/8 the 1 3/4 are superior for engines under 550WHP. the 1 3/4 extractors reduce down a lot more in the collectors than the larger shorter 1 7/8" set
Last edited by RomanNYC; Aug 25, 2016 at 02:12 PM.