1 3/4 or 1 7/8 kooks headers for ls3 ???
05-21-2018, 04:57 PM
#41
Racer
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
05-21-2018, 05:05 PM
#42
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
05-21-2018, 05:46 PM
#43
Le Mans Master
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.
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.
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Bigwebb (05-21-2018)
05-22-2018, 08:05 PM
#44
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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.
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.
05-23-2018, 06:07 AM
#45
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
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 06:12 AM.
05-23-2018, 08:20 AM
#47
Racer
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
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
05-23-2018, 12:27 PM
#48
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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?
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?
05-23-2018, 12:46 PM
#49
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?
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?
05-23-2018, 01:06 PM
#50
Racer
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
05-23-2018, 01:12 PM
#51
05-23-2018, 01:19 PM
#52
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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.
05-23-2018, 01:24 PM
#53
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.
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
05-23-2018, 01:35 PM
#54
Instructor
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
05-23-2018, 01:43 PM
#55
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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.
05-23-2018, 02:00 PM
#56
Instructor
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.
05-23-2018, 02:13 PM
#57
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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
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
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.
05-23-2018, 03:18 PM
#59
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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.
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.
05-23-2018, 03:52 PM
#60
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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.
