Due to the questions he received about 'at what HP level do I need to consider larger headers', here's another test from Richard, comparing primary diameters on a 383 LS and a Whipple 383.

 

Definitely not worth worrying over too much for NA based on Richard Holener's dyno results in . I'll stick with the 1 7/8 on the 383+ LS1. Matches pretty close to what TSP, VR & LPE have shared previously +5 to 8 hp for 1 7/8 vs 1 3/4

Moral seems to be we should pay attention to the full exhaust (collectors & Y pipe, X pipe, true dual etc)

 

well it could be a good chunk. The engine gained 25hp on top with the SC from going 1 3/4 to 1 7/8

edit also remember t
he was running a 3" collector so it be advisable to run a 3" all the back.

 

Some points you guys are missing.....

First off, look at the different in the collectors between the two headers. We all know header collector design does play a role in this. the 1 3/4 headers have a better design collector where its longer and more gradual into the merge. Also, the supercharged 383 MADE MORE POWER with less boost. Bring the boost back to where it was.....well, I think we all know what will happen.

My opinion on this..... a 5.3, 5.7 and even most 6 liter engines won't need/benefit from 1 7/8.... but if you plan on more power, bigger engine or boost/nitrous later on, maybe just do the bigger headers from the onset so You arent spending money twice and/or regretting you didnt go bigger in the beginning. A 6.2 thats pretty stout with big heads and especially big exhaust ports will likely benefit....and over 400cu. in. making big power will benefit.

Sometimes I feel like his "tests" are quite like comparing apples to oranges in alot of ways and the average uninformed tinkerer will not know any better that details are being left out....that really matter.

 

Yes the longer collector and then the merge if there is one is probably beneficial for most setups I would imagine.

my setup is pretty simple but I still feel lost about headers for it lol.

4th gen Camaro: cam only LQ9 with a 233/243 -114+5 and the stock ls6 intake but it's still got a nice 7500rpm rev limit and So it could also use a better intake. Behind that a 4k stall 4L60e with 4:10 gears and 26" tires.

For exhaust I've got the eBay version (wonky tips) of the speed-e 3" duals that go out the back on the car and my old pace setter coated 1-3/4" headers from like 2004 are still kicking it

I would like to see a common and imperfect (has to fit on an actual car) exhaust like mine on holders dyno tried with a few different headers to see what works best. There is a nice x-pipe in my exhaust but the driver's side piping is much longer even before the x than the passenger side and it's even longer after that. The shorter passenger piping gets it's tips on that side dirty much faster after some driving so obviously there is a difference in flow on either side.

Thoughts?

 

The point is, not every combo will produce the same outcome. Like Che70velle said.

 

I wish I saw this video before I ordered by headers. lol. 600 rwhp.....probably translates to around 700 flywheel........... I would've been fine with the smaller headers. Oh well......

 

I would say you're not leaving much off the table and especially not enough to pay for new headers and bother with installing them.......

Off topic.....I've got a procharged setup but shooting for low 600s. Do you have stock internals? (rods in particular). My tuner told me I'll be fine as long as I keep the rpms under 7000 and horsepower under 650 and torque under 600.
edit: Sorry, I just saw in your signature that you have a forged ls3 and probably all the upgraded goodies inside. lol

 

if the tuner knows what they are doing, I think your set will be OK with stock internals 👍

 

People have put 1 7/8" headers on stock ls1s before with (fuzzy memory) no loss, I also believe some reported gains over their previous 1 3/4" setups. I take everything holdener says with a grain of salt these days because YouTube clicks.

 

What reason would Richard have to distort stats between two header sizes? If it were different name brand products I could see possibilities there. He has made his rep on straightforward dyno tests.
How would you know there was no loss with the 1 7/8" headers unless they directly replaced some 1 3/4" headers? You didn't mention any previous headers

 

I enjoy most of his videos, he’s a lively soul. But a good scientific, controlled comparison is definitely not what he’s about. A lot of times he will compare some **** that similar, but aren’t the sane engines. Example. He may test this cam or that cam, same size engine, but not same engines on the same day. Then compare those two graphs. Might even have different heads. To me, that’s not a fair test at all. I honestly think he’s doing it for the views and whatever money he gets. Sometimes he will post stuff that would be acceptable, but most of the time he’s pulling graphs and comparing in past tests. How is that valid?

 

A lot of what he compares is what people ask about. If he has done tests in the past that are very close, that is what gets put up. He WILL point out differences between test subjects and how that affects the test. Sometimes those differences don't affect the target outcome of the test, and he will also point that out. You can't just see the parts tested and skip to the dyno chart. Dyno time isn't cheap, and I doubt he's getting wealthy off this. Hopefully a decent living....

 

His income (part? all? I have no idea but some is) based on clicks. If you can title a video "Your headers are too big?!!!111!?!@!@?!@" or something clickbaity and then show a tiny difference at 3000rpms to justify that difference, it makes me suspicious of all your claims. My suspicion started when he came out with that video about 706 heads being better than 243 heads. After that I wrote off almost everything he says as the typical YouTube clickbait progression to keep viewership up. Same with these tests.

These tests were done more than a decade ago and are on here some place. I don't remember what brand was what or any of the details other than this used to be an argument when 1 7/8 headers first became readily available for fbodies. The common consensus was that they were way too big unless it was some high compression drag race only stroker. Then people started testing them on stock engines and proved people wrong. Now, I do not believe (within logical reason of course) that you can have too big of a header on an engine. But that's personal opinion and no proof or experience to back it up so take it for what it is.

 

Lol Your not making a killing off of 2700 average video views. All tests and comparisons should be viewed with a common sense approach. I would trust holdener over these LS super dyno frauds that linger on the forums and YouTube that post clickbait dynos to try to get more business.

 

I don't think Holdener even mentioned the results in the title? So, I'm not sure it's clickbait? I think that he would get pretty much the same number of views no matter what the results were. Although, a few extras clicking on it from this thread maybe

 

That's correct. I'm glad I'm not the only one that recalls those details from long ago.

There was lots of controversy and the 1 7/8's generally came out as better overall based on what was posted. I posted a search and links to some of those threads earlier in this thread.

We all know different dyno, different day different set up means we can't say absolutely without testing.

I like Richard Holdener and his video's but there's nothing new about 1 7/8 headers in his video that Texas Speed, Lingenfelter and many others haven't shared with their testing many years ago.

Couple years ago, considered putting Lingenfelter's little GT2-3 cam (207/220 .571/.578 118.5) in my nearly stock 02 Z28. Talked in detail with LPE about best headers to purchase 1 3/4 vs 1 7/8 for that cam for best performance. Based on LPE's dyno results answer was a quality set of 1 7/8 headers.

RH provides as honest and accurate information as his budget allows and I'm grateful for it. However, one still needs to do the appropriate research for their project and not take YouTube video as gospel or at face value.

 

Technically you need to compare apples to apples but that is problematic. Testing same brand would be consistent but even TSP 1 3/4 and 1 7/8 header collectors look slightly different. Different brands run the tubing different.

I think his conclusion is probably valid. Smaller tubes on the street and larger tubes for track. Your butt dyno probably won't know the difference though.

 

On Mamo's test in another forum/thread he DOES put in the disclaimer that he is speaking of WOT only. I think tubing size MIGHT affect part throttle response one way or the other.

 

In-vehicle results with full exhaust won’t necessarily mirror engine dyno.

Below is a link to the thread mentioned in quote.

https://ls1tech.com/forums/generatio...o-results.html