Notices
C6 Tech/Performance LS2, LS3, LS7, LS9 Corvette Technical Info, Internal Engine, External Engine, Tech Topics, Basic Tech, Maintenance, How to Remove & Replace
Sponsored by:
Sponsored by:

1 3/4 or 1 7/8 kooks headers for ls3 ???

 
Old 05-21-2018, 05:57 PM
  #41  
KW Baraka
CF Senior Member
 
KW Baraka's Avatar
 
Member Since: Jan 2015
Location: San Antonio TX
Posts: 257
Thanked 8 Times in 8 Posts
Default

Originally Posted by redbird555 View Post
No reason to go with either size....2" has been shown to make more power everywhere even on a bone stock ls3. why would you leave power on the table if youre starting out fresh with a new setup
1. Cost

2. Fitment

If the cost of a 2" header is reasonable vs a 1 7/8".....AND.....the headers fit without much huss or fuss, then I agree.

If either of these two are an issue, then the 'buyer' needs to conduct his own 'cost/benefit analysis'.

If the buyer already has a solid 1 3/4" set (like the OP), well things get that much more interesting in regards to whether he should go bigger.....

KW
KW Baraka is offline  
Old 05-21-2018, 06:05 PM
  #42  
redbird555
CF Senior Member
 
Member Since: Nov 2009
Posts: 1,286
Thanked 85 Times in 79 Posts
Default

If you buy new the difference is less than a hundred bucks. As far as fitment goes mine clear everything just fine. I have ARH on my Z and they fit way better being 2” than my old 1-7/8 looks did
redbird555 is offline  
Old 05-21-2018, 06:46 PM
  #43  
old motorhead
CF Senior Member
 
Member Since: Dec 2005
Location: Southeast TX
Posts: 4,179
Thanked 125 Times in 114 Posts
Default

I had two Magnuson blown LS3's. One with 1.75" headers and the other with 1.875". The one with the smaller headers actually made almost the same power as the one with the bigger headers. 640ish at the wheels. The one with the bigger headers actually had a little more boost and a slightly bigger cam.

Probably goes back to what was mentioned ad nauseum. Dyno diffs. If I buy new, I'll buy 1.875's for my mild, cam only build. No reason not to. If I find a really clean set of used 1.75's for a good price, I'll buy them. No way would I pull off a perfectly good set of 1.75's looking for more power.
old motorhead is offline  
The Following User Says Thank You to old motorhead For This Useful Post:
Bigwebb (05-21-2018)
Old 05-22-2018, 09:05 PM
  #44  
449er
CF Senior Member
 
449er's Avatar
 
Member Since: Apr 2016
Location: Pittsburgh
Posts: 2,133
Thanked 261 Times in 223 Posts
Default

Originally Posted by old motorhead View Post
I had two Magnuson blown LS3's. One with 1.75" headers and the other with 1.875". The one with the smaller headers actually made almost the same power as the one with the bigger headers. 640ish at the wheels. The one with the bigger headers actually had a little more boost and a slightly bigger cam.

Probably goes back to what was mentioned ad nauseum. Dyno diffs. If I buy new, I'll buy 1.875's for my mild, cam only build. No reason not to. If I find a really clean set of used 1.75's for a good price, I'll buy them. No way would I pull off a perfectly good set of 1.75's looking for more power.
Are you reading this Redbird?
449er is offline  
Old 05-23-2018, 07:07 AM
  #45  
redbird555
CF Senior Member
 
Member Since: Nov 2009
Posts: 1,286
Thanked 85 Times in 79 Posts
Default

Originally Posted by 449er View Post
Are you reading this Redbird?
not really sure what your point is? I said if startin outbfresh there’s no reason not to go with 2”. I invite you to prove me wrong but I don’t see how you could since they’re more or less the same cost and make more power.

nowbfor the guy above he had 2 sets of headers and made x power. Sure they worked but how will he know if he wouldn’t have gained more power? Stock exhaust manifolds would have worked with his build too it’s not like the car wouldn’t have ran lmao. But he would have surely gained power. Same applies to headers. I’ve been there and tested countless headers sets 2” always made more power. On the same car, on the same dyno...unlike the guy above who tested it on different cars.

So once again i really dont understand the point of your post. Do you have any back to back data or testimonials? By the looks of you riding off someone else post most likely not

you also understand the comparison above is pretty useless. You have 2 completely different setups on different dynos most like at different days. Seriously man? Lol

Last edited by redbird555; 05-23-2018 at 07:12 AM.
redbird555 is offline  
Old 05-23-2018, 08:56 AM
  #46  
BigMonkey73
CF Senior Member
 
Member Since: Oct 2013
Location: Dallas TX
Posts: 853
Thanked 82 Times in 72 Posts
St. Jude Donor '15
Default

https://youtu.be/_PVXvHkr-Vs
BigMonkey73 is offline  
Old 05-23-2018, 09:20 AM
  #47  
KW Baraka
CF Senior Member
 
KW Baraka's Avatar
 
Member Since: Jan 2015
Location: San Antonio TX
Posts: 257
Thanked 8 Times in 8 Posts
Default

Originally Posted by BigMonkey73 View Post
https://youtu.be/_PVXvHkr-Vs
Well.....shows that a 3" exhaust is making more power than a 2 1/2" exhaust while also weighing a bit more.

Says nothing about headers.....I've seen several back to back dyno tests and bigger header tubes always made more power throughout the power band.

KW
KW Baraka is offline  
Old 05-23-2018, 01:27 PM
  #48  
HOXXOH
CF Senior Member
 
HOXXOH's Avatar
 
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 14,149
Thanked 858 Times in 715 Posts
Default

And we're back to debating header primary sizes after an 8 year break on this thread.

I think the last post in 2010 (post #34) said more about power differences than any other.

Lets talk about brands, or tri-Y vs identical length, or materials, or collectors, or tube length, or X vs H pipe, or Countries of manufacture, since somehow that always comes up as being of great importance.

Because the whole point of headers is to move exhaust gasses more efficiently from the engine to atmosphere, the real key is in determining the volume, temperature, and velocity of the gasses being produced.

Just for reference, both Dennis50NJ (RIP) and myself used 1.75" primaries when setting the still unbroken bolton records on this forum. Even though our dyno charts show significantly different numbers, the bottom line is: What did we know, that others don't?
HOXXOH is offline  
Old 05-23-2018, 01:46 PM
  #49  
redbird555
CF Senior Member
 
Member Since: Nov 2009
Posts: 1,286
Thanked 85 Times in 79 Posts
Default

Originally Posted by HOXXOH View Post
And we're back to debating header primary sizes after an 8 year break on this thread.

I think the last post in 2010 (post #34) said more about power differences than any other.

Lets talk about brands, or tri-Y vs identical length, or materials, or collectors, or tube length, or X vs H pipe, or Countries of manufacture, since somehow that always comes up as being of great importance.

Because the whole point of headers is to move exhaust gasses more efficiently from the engine to atmosphere, the real key is in determining the volume, temperature, and velocity of the gasses being produced.

Just for reference, both Dennis50NJ (RIP) and myself used 1.75" primaries when setting the still unbroken bolton records on this forum. Even though our dyno charts show significantly different numbers, the bottom line is: What did we know, that others don't?
Didn’t lazers car go 10.58 at over 130. Iirc that’s a much better trap than your record was. And he has 2”-2 1/4 headers
redbird555 is offline  
Old 05-23-2018, 02:06 PM
  #50  
KW Baraka
CF Senior Member
 
KW Baraka's Avatar
 
Member Since: Jan 2015
Location: San Antonio TX
Posts: 257
Thanked 8 Times in 8 Posts
Default

Originally Posted by HOXXOH View Post
......Just for reference, both Dennis50NJ (RIP) and myself used 1.75" primaries when setting the still unbroken bolton records on this forum.......


And of course......there's no way you would've made more power or gone faster with 1 7/8" or 2" headers.....right?

Just asking for......reference.

KW
KW Baraka is offline  
Old 05-23-2018, 02:12 PM
  #51  
redbird555
CF Senior Member
 
Member Since: Nov 2009
Posts: 1,286
Thanked 85 Times in 79 Posts
Default

Originally Posted by KW Baraka View Post


And of course......there's no way you would've made more power or gone faster with 1 7/8" or 2" headers.....right?

Just asking for......reference.

KW
Except the current bolt on record holder has 2” headers idk why he won’t acknowledge that lol
redbird555 is offline  
Old 05-23-2018, 02:19 PM
  #52  
HOXXOH
CF Senior Member
 
HOXXOH's Avatar
 
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 14,149
Thanked 858 Times in 715 Posts
Default

Originally Posted by redbird555 View Post
Didn’t lazers car go 10.58 at over 130. Iirc that’s a much better trap than your record was. And he has 2”-2 1/4 headers
Can't you understand his car is not a bolton, since the 1.85 rockers effectively do the same thing as an aftermarket cam or do you not understand the rules or how stuff works? Apparently you don't even know if his headers are 2" or 2 1/4" either. Try checking stuff before you post crap.
HOXXOH is offline  
Old 05-23-2018, 02:24 PM
  #53  
redbird555
CF Senior Member
 
Member Since: Nov 2009
Posts: 1,286
Thanked 85 Times in 79 Posts
Default

Originally Posted by HOXXOH View Post
Can't you understand his car is not a bolton, since the 1.85 rockers effectively do the same thing as an aftermarket cam or do you not understand the rules or how stuff works? Apparently you don't even know if his headers are 2" or 2 1/4" either. Try checking stuff before you post crap.
Lol rockers have been a bolt on for years in many different platforms. And he obliterated your time and mph if rockers gain 6mph why doesn’t everyone do them? I mean crap you could take the record back if you’d just do rockers and gain 5-6 mph

Also his headers are STEPPED so no I wasn’t wrong. Sot and maybe think for a sec you don’t know everything and maybe you can get that bolt on record back lol
redbird555 is offline  
Old 05-23-2018, 02:35 PM
  #54  
lazerlemonta
CF Senior Member
 
lazerlemonta's Avatar
 
Member Since: Aug 2017
Location: Virginia
Posts: 137
Thanked 0 Times in 0 Posts
Default

I likely have the only set of the new hooker tri y headers that are 2"x2 1/4"x 2 1/2" x 3" on a stock head stock cam LS3. I posted a review thread and got zero comments. The headers are worth a solid 10 RWHP from 6200 up. Really I wasnt far off of the record bolt on time with no headers lol these rockers are wicked being worth a whole 8hp
lazerlemonta is offline  
Old 05-23-2018, 02:43 PM
  #55  
HOXXOH
CF Senior Member
 
HOXXOH's Avatar
 
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 14,149
Thanked 858 Times in 715 Posts
Default

Originally Posted by KW Baraka View Post


And of course......there's no way you would've made more power or gone faster with 1 7/8" or 2" headers.....right?

Just asking for......reference.

KW
Dennis did swap to 1 7/8" headers and ran slower, so he went back to the 1 3/4". I am already running faster than other guys who are using 1 7/8" headers, so see no incentive to make a change. If you'd like to supply me with either size headers that'll mate to my X-pipe, I'll do the labor to make the change and test the difference. Don't plan on anything being returned other than the track results.
HOXXOH is offline  
Old 05-23-2018, 03:00 PM
  #56  
lazerlemonta
CF Senior Member
 
lazerlemonta's Avatar
 
Member Since: Aug 2017
Location: Virginia
Posts: 137
Thanked 0 Times in 0 Posts
Default

Originally Posted by HOXXOH View Post
Dennis did swap to 1 7/8" headers and ran slower, so he went back to the 1 3/4". I am already running faster than other guys who are using 1 7/8" headers, so see no incentive to make a change. If you'd like to supply me with either size headers that'll mate to my X-pipe, I'll do the labor to make the change and test the difference. Don't plan on anything being returned other than the track results.
Just out of curiosity what is your current ET and Trap? Headers were my last mod for the simple fact we thought we could dip into the 10s on stock exhaust. Really you can run 10.8 pretty slick on it likely even faster. I got in a hurry for a track rental and finished the car. Realistically 127-128 mph is obtainable as well.
lazerlemonta is offline  
Old 05-23-2018, 03:13 PM
  #57  
HOXXOH
CF Senior Member
 
HOXXOH's Avatar
 
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 14,149
Thanked 858 Times in 715 Posts
Default

Originally Posted by redbird555 View Post
Lol rockers have been a bolt on for years in many different platforms. And he obliterated your time and mph if rockers gain 6mph why doesn’t everyone do them? I mean crap you could take the record back if you’d just do rockers and gain 5-6 mph

Also his headers are STEPPED so no I wasn’t wrong. Sot and maybe think for a sec you don’t know everything and maybe you can get that bolt on record back lol
Obviously, you don't understand the rules here and apparently lazerlemonta does, since he posted his timeslips for inclusion into the forum performance list under the category for LS3 internal modifications. See https://www.corvetteforum.com/forums...post1597056055

You never said stepped headers, as in size changes for adjoining pipes, or that the size changes weren't limited to just those two. So yeah, you were wrong. You can either tell the whole truth or it's meaningless. You sound like a liberal snowflake that can't handle reality.

See what I mean about checking stuff before posting.
HOXXOH is offline  
Old 05-23-2018, 03:48 PM
  #58  
Bigwebb
CF Senior Member
 
Member Since: Aug 2007
Posts: 1,252
Thanked 13 Times in 13 Posts
Default

so in measuring a set of unknown headers, am I looking for outer diameter of the pipe or inner diameter?
Bigwebb is offline  
Old 05-23-2018, 04:18 PM
  #59  
HOXXOH
CF Senior Member
 
HOXXOH's Avatar
 
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 14,149
Thanked 858 Times in 715 Posts
Default

Originally Posted by lazerlemonta View Post
Just out of curiosity what is your current ET and Trap? Headers were my last mod for the simple fact we thought we could dip into the 10s on stock exhaust. Really you can run 10.8 pretty slick on it likely even faster. I got in a hurry for a track rental and finished the car. Realistically 127-128 mph is obtainable as well.
The 10.802 @ 126.84 is my PB. That was on a trip to Sacramento Raceway in Jan 2015. The DA was -506'. The track prep was not great, since the 60' on that pass was only 1.54. Here in Phoenix a few weeks later with good prep, my 60' was in the 1.48 - 1.50 range. The ET's were in the 10.90's and MPH's in the mid 125's when the DA was 1200'+.

I haven't been to the track much after that, due to the way management decided to only run open track once a month and combined it with time trials for big events taking place the following day. When they charge $40 and the crowd is so big you only get one pass in 5 hours, the fun is gone. My racing buddy crashed his car over a year ago and I haven't run since then. Maybe I'll play some next Winter. The DA here will never go negative, so I don't expect much. I've even slowed down everyday driving. I turned 150K miles last Sept and not yet at 153K.

I hope you keep going forward with your mods. You already got a great start, so I'm wishing you the best.
HOXXOH is offline  
Old 05-23-2018, 04:52 PM
  #60  
HOXXOH
CF Senior Member
 
HOXXOH's Avatar
 
Member Since: Sep 2007
Location: Peoria/Phoenix AZ
Posts: 14,149
Thanked 858 Times in 715 Posts
Default

Originally Posted by Bigwebb View Post
so in measuring a set of unknown headers, am I looking for outer diameter of the pipe or inner diameter?
The standard method for tubing is OD x wall thickness. Such as 1.50 x .083 etc. The type of manufacturing method is somewhat important, since HREW is not the best choice for headers compared to DOM, but it is cheaper.
HOXXOH is offline  

Thread Tools
Search this Thread
Quick Reply: 1 3/4 or 1 7/8 kooks headers for ls3 ???


Sponsored Ads
Vendor Directory

Contact Us - About Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: