[Dmoney2SS]

How much more power do headers actually bring compared to the factory manifolds? I’m sure they add power but is it worth the cost of the headers?

[Joshinator99]

Originally Posted by Dmoney2SS

How much more power do headers actually bring compared to the factory manifolds? I’m sure they add power but is it worth the cost of the headers?

Headers are more effective if you package them with E85, a better intake manifold and throttle body IMO. You’ll need a tune so might as well make it worthwhile.

[Dmoney2SS]

Originally Posted by Joshinator99

Headers are more effective if you package them with E85, a better intake manifold and throttle body IMO. You’ll need a tune so might as well make it worthwhile.

Yeah my intent was to do lt2 manifold and go catless headers depending on how much you actually make with headers, I plan on doing a cam swap further down the line but I figured the lt2 + catless would be good for a daily driver for now. I was just curious as to how much of a difference the headers make vs the stock manifolds since the factory ones seem like they flow pretty well

[Joshinator99]

Originally Posted by Dmoney2SS

Yeah my intent was to do lt2 manifold and go catless headers depending on how much you actually make with headers, I plan on doing a cam swap further down the line but I figured the lt2 + catless would be good for a daily driver for now. I was just curious as to how much of a difference the headers make vs the stock manifolds since the factory ones seem like they flow pretty well

Not a lot to be gained in your scenario. Headers with no cats are maybe 15-20 WHP with half of that gain coming from no cats. Really not worth it IMO. Headers would be worth revisiting with cam and additional mods but could still run high flow cats with virtually no HP loss.

[Dmoney2SS]

Originally Posted by Joshinator99

Not a lot to be gained in your scenario. Headers with no cats are maybe 15-20 WHP with half of that gain coming from no cats. Really not worth it IMO. Headers would be worth revisiting with cam and additional mods but could still run high flow cats with virtually no HP loss.

Yeah, my intent was to do headers further down the line when it becomes more necessary for them but I wanted some input to see if they were really worth it

[6spdhyperblue]

if you go n/a you don’t have many options to get the car to run faster.

I’d do a ati pulley first if you don’t want to change the exhaust now.

It’s much cheaper, easier to install, and improves engine smoothness and durability.

If the catless headers get you 2mph in the 1/4. The pulley prob worth .8mph

[KingLT1]

There isn't a big difference in power from catless stock headers to catless long tube headers. It's only about a 20whp difference on a 700whp FI car. So on something under 500whp you might see 10whp. The biggest restriction is in the cat pipes. That being said you might as well just do long tube headers because there isn't any cat delete pipes available anymore unless you find a used set.

[Sillysspeed]

Is this what you’re talking about? Still available?

[Dmoney2SS]

Originally Posted by KingLT1

There isn't a big difference in power from catless stock headers to catless long tube headers. It's only about a 20whp difference on a 700whp FI car. So on something under 500whp you might see 10whp. The biggest restriction is in the cat pipes. That being said you might as well just do long tube headers because there isn't any cat delete pipes available anymore unless you find a used set.

If you don’t mind sharing, are you sbe with forged internals or stock everything? Or built

[KingLT1]

Originally Posted by Sillysspeed

Is this what you’re talking about? Still available?

Yeah I run those. They haven't been available for about 5years now. I believe the owner passed. Not sure why the page is still up. Then New Era started making something similar but discontinued them about 2yrs ago.

Originally Posted by Dmoney2SS

If you don’t mind sharing, are you sbe with forged internals or stock everything? Or built

My engine internally is still OE stock.

[Dmoney2SS]

Originally Posted by KingLT1

Yeah I run those. They haven't been available for about 5years now. I believe the owner passed. Not sure why the page is still up. Then New Era started making something similar but discontinued them about 2yrs ago.



My engine internally is still OE stock.

How many lbs of boost are you able to run like that? And I believe I found some speed engineering catless midpipes for the factory manifolds so I was leaning towards those

[KingLT1]

Originally Posted by Dmoney2SS

How many lbs of boost are you able to run like that? And I believe I found some speed engineering catless midpipes for the factory manifolds so I was leaning towards those

The first year I ran 8-9psi with full E85. Second year 9-10psi with E60. The last 2 seasons has been on 10-11psi with E60. Setup remains unchanged this season.

Side note, I would not attempt this with pump gas. I am also not super aggressive with the timing. I run 19.5 degrees at 10-11psi. The key on these Stock bottom ends' is to keep the cylinder temps as low as possible. Ethanol helps substantially with that. The LT1 has very tight ring gaps and that leaves little room for expansion. Also make sure you have plenty of fuel system. Currently DI fuel upgrades are insanely expensive. If I was starting in 2023 I would probably go right to a ToohighPSI port system.

Pretty sure those catless mids only remove the secondary cats not the primary. The main restriction is in the primary pipes. The pipe necks down under 2" before entry to the cats.

[oldman]

I have run stock headers with cats, with modified front cats, with CA offroad pipes, Kooks headers with and without cats. I like stock headers, CA offroad pipes, second I like the modified stock front cats remove rear cats ( front cat driver side needs to be cut just after the first flanged and the pipe rounded back out, front 02 spaced much further out of the flow, ZL1 is slightly bigger in this location which is the only difference between Camaro exhaust.

I also did not mind the 1 and 7/8 header with cats, sound was about equal to the stock header and CA cat deletes and OEM second cats.

Power well full built I'd say about 25 HP in favor of long tube, at 6 PSI or so maybe 10 to 15 WHP. Power uncapped or a low restriction 3" probably +10 WHP in favor of longtube. On street tire, you won't see any performance inprovement as any decent FI setup can more the overwhelm any 200 wear tire to mid 3rd gear say 85 MPH...

I have put dumps at the crush bend and this give the same sound as a low restriction 3" and long tubes, power feels up to, but you can go stone deaf with the this setup; clearly you get street chops at the local cars and coffee when you pull in with a large cam engine and dumps... LOL

Forgot to add I had to partially wrap my LT passenger side and blanket and wrap the starter or it would just cook the starter during a 110 degree day street traffic.

[NA18CamaroSS]

My experience with headers on this platform is that they do not gain power over the stock manifolds with cat deletes. I tried the ARH 1 7/8 " headers a couple of years ago, and after spending a bunch of money on tuning and dyno time, the car made the same power ~480 RWHP. I recently gave headers a second try, this time Kooks 1 7/8 long tubes. The car did not gain 1 HP worth of peak HP. There were some modest gains at 5,500 RPM. It seems like there is a 500 WHP ceiling when running the stock bottom end and the stock cam. Car has Pray ported heads, Pray ported MSD, RotoFab, 103 mm TB, and runs on E85.
500 RWHP is nice, but there is always room for improvement.