1 7/8 AR Headers on a lightly modded ls1
The best part about the article that I posted is that the average torque was higher on the 1 7/8 headers than the 1 3/4's. Also the 1 7/8 peaked at the same torque # but 600 rpms lower in the curve. So the 1 7/8 had more everything.
Power Numbers
Avg. Avg. Peak Peak
Combo TQ HP TQ HP
TTS 1 3/4
Headers 372.5 302.5 396 @5,000 396 @5,700
TTS 1 7/8
Headers 373.1 303.3 396 @4,400 402 @5,800
Interesting isnt it. Make your choice wisely
Power Numbers
Avg. Avg. Peak Peak
Combo TQ HP TQ HP
TTS 1 3/4
Headers 372.5 302.5 396 @5,000 396 @5,700
TTS 1 7/8
Headers 373.1 303.3 396 @4,400 402 @5,800
Interesting isnt it. Make your choice wisely
The best part about the article that I posted is that the average torque was higher on the 1 7/8 headers than the 1 3/4's. Also the 1 7/8 peaked at the same torque # but 600 rpms lower in the curve. So the 1 7/8 had more everything.
Power Numbers
Avg. Avg. Peak Peak
Combo TQ HP TQ HP
TTS 1 3/4
Headers 372.5 302.5 396 @5,000 396 @5,700
TTS 1 7/8
Headers 373.1 303.3 396 @4,400 402 @5,800
Interesting isnt it. Make your choice wisely
Power Numbers
Avg. Avg. Peak Peak
Combo TQ HP TQ HP
TTS 1 3/4
Headers 372.5 302.5 396 @5,000 396 @5,700
TTS 1 7/8
Headers 373.1 303.3 396 @4,400 402 @5,800
Interesting isnt it. Make your choice wisely
What C5 (or C6) have you seen lose their stock manifolds in place of long tubes and not see HUGE gains across the curve assuming a quality header was swapped in their place??
This testing showed tiny single digit gains with the addition of long tube headers (3 ft/lbs and 2 HP increase in average TQ and power respectively!)
Doesnt seem like anything real world was tested there....
Anyone thats swapped a set of long tubes in their Vette knows how much there is to gain from a swap to a well designed header....and you guys have all seen the results....Im not telling you anything you dont already know.
I dont know what was exactly wrong in that testing and how there seemed to be no gains from the better scavenging of the long tube pipes but there is no doubt that something was holding that engine back.
Just my .02
Tony
That entire round of testing seems very flawed if you ask me....
What C5 (or C6) have you seen lose their stock manifolds in place of long tubes and not see HUGE gains across the curve assuming a quality header was swapped in their place??
This testing showed tiny single digit gains with the addition of long tube headers (3 ft/lbs and 2 HP increase in average TQ and power respectively!)
Doesnt seem like anything real world was tested there....
Anyone thats swapped a set of long tubes in their Vette knows how much there is to gain from a swap to a well designed header....and you guys have all seen the results....Im not telling you anything you dont already know.
I dont know what was exactly wrong in that testing and how there seemed to be no gains from the better scavenging of the long tube pipes but there is no doubt that something was holding that engine back.
Just my .02
Tony
What C5 (or C6) have you seen lose their stock manifolds in place of long tubes and not see HUGE gains across the curve assuming a quality header was swapped in their place??
This testing showed tiny single digit gains with the addition of long tube headers (3 ft/lbs and 2 HP increase in average TQ and power respectively!)
Doesnt seem like anything real world was tested there....
Anyone thats swapped a set of long tubes in their Vette knows how much there is to gain from a swap to a well designed header....and you guys have all seen the results....Im not telling you anything you dont already know.
I dont know what was exactly wrong in that testing and how there seemed to be no gains from the better scavenging of the long tube pipes but there is no doubt that something was holding that engine back.
Just my .02
Tony
I agree with you completely. Nobody makes that little of a gain when adding headers. I think that this article was worth mentioning because the comparison between collector sizes and their results.
Productive contribution with some data and experience would be nice versus crappy commentary. I know from your post history that you have the knowledge and background.
Some of us who are in exactly the same boat, as we speak, as the OP are trying to help him make an informed decision based on facts, subjective first hand experience, and overall considerations. Pissing matches aside, there's some good info here with more to come. Amazing how hard it can be to conclusively answer the question "Good or bad?" for a given application, huh?
Some of us who are in exactly the same boat, as we speak, as the OP are trying to help him make an informed decision based on facts, subjective first hand experience, and overall considerations. Pissing matches aside, there's some good info here with more to come. Amazing how hard it can be to conclusively answer the question "Good or bad?" for a given application, huh?
Check out this link. In this instance the 1 7/8 header showed superior to the 1 3/4 on a stock motor.
http://www.carcraft.com/techarticles...est/index.html
I am not saying this is always the case or that this test is right. But something to think about.
Btw those collectors just dont look right. IMO
http://www.carcraft.com/techarticles...est/index.html
I am not saying this is always the case or that this test is right. But something to think about.
Btw those collectors just dont look right. IMO
This corresponds exactly to my experience and is one half step towards supporting my theory. One header to the other, no discernible difference (1% - that's a standard deviation) either way, total wash. We'll see what the dyno says next week, both before and after a retune.
There's enough variation in header performance nowadays (or most any other part) that you need to retune to get the benefit. If you don't, I suspect most any well-designed header will show virtually the same results.
Now that I think about it, it's a little surprising it shows any benefit at all with tuning for a different part.
Will a SI car gain swapping from 1 3/4" to 1 7/8" headers?
https://ls1tech.com/forums/showthrea...hlight=headers
https://ls1tech.com/forums/showthrea...hlight=headers
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Guys I don't know if this helps but why has no one called Nick at ARH?
On Tuesday, I spoke with Nick about my ride and order a new set of headers. I currently have 1 3/4 Jethot Headers on my car with 14 inch trun downs. I just took my car last Saturday to Bowling Green, KY to Beech Bend Raceway and it ran 10.75 at 123 MPH's N/A with a 1.44 sixty foot time at 3,435 lbs. The car is 346 CI with AFR heads and Fast90 with NW90.
I give the details to Nick after answering all of the questions he is building me 1 3/4 headers for my setup. I told him money was no issue and he said my setup would not need 1 7/8 headers even after I also told him I have a dry NOS kit and plan to run a 100 shot which should put me somewhere around 10.30's at 129 MPH's.
I trusted in the fact he knows what he is doing and knows what your setup actually needs. I also add if you are not at the track with you car a lot, you are more then likely not going to know if 1 3/4 or 1 7/8 headers will really make a difference so therefore buy the 1 7/8's and move on, does it really matter if your 346 CI daily driver is producing the max power and TQ that it can, to just drive up and down the road?
I mean after all you can only go 30 in the City, 55 on the highway and 70 on the interstate so what does it matter!!
I know my car is not a big CI engine, but I want it to run as good as it can and I will change out the headers and take it to the track to see if there is a difference in times.
Don't ask me for Dyno numbers we do our tunning at the track with a wide band and HP Tuners so I guess we will see what difference ARH's make!
On Tuesday, I spoke with Nick about my ride and order a new set of headers. I currently have 1 3/4 Jethot Headers on my car with 14 inch trun downs. I just took my car last Saturday to Bowling Green, KY to Beech Bend Raceway and it ran 10.75 at 123 MPH's N/A with a 1.44 sixty foot time at 3,435 lbs. The car is 346 CI with AFR heads and Fast90 with NW90.
I give the details to Nick after answering all of the questions he is building me 1 3/4 headers for my setup. I told him money was no issue and he said my setup would not need 1 7/8 headers even after I also told him I have a dry NOS kit and plan to run a 100 shot which should put me somewhere around 10.30's at 129 MPH's.
I trusted in the fact he knows what he is doing and knows what your setup actually needs. I also add if you are not at the track with you car a lot, you are more then likely not going to know if 1 3/4 or 1 7/8 headers will really make a difference so therefore buy the 1 7/8's and move on, does it really matter if your 346 CI daily driver is producing the max power and TQ that it can, to just drive up and down the road?
I mean after all you can only go 30 in the City, 55 on the highway and 70 on the interstate so what does it matter!!
I know my car is not a big CI engine, but I want it to run as good as it can and I will change out the headers and take it to the track to see if there is a difference in times.
Don't ask me for Dyno numbers we do our tunning at the track with a wide band and HP Tuners so I guess we will see what difference ARH's make!
Last edited by N2RACINGLS1's; Mar 29, 2008 at 08:12 AM.
Ok, tune coming tomorrow. Will let you guys know how it goes.
BTW, I just added 17x11 rears since the last dyno. Will that make enough difference to warrant putting the 17x9s back on for the dyno tune tomorrow? I've also changed the plugs, fuel filter, and doen a half *** injector cleaning so I think that may offset the heavier wheels. What are your thoughts?
BTW, I just added 17x11 rears since the last dyno. Will that make enough difference to warrant putting the 17x9s back on for the dyno tune tomorrow? I've also changed the plugs, fuel filter, and doen a half *** injector cleaning so I think that may offset the heavier wheels. What are your thoughts?
TECH Senior Member
iTrader: (3)
Joined: Apr 2006
Posts: 6,524
Likes: 1
From: Western Burbs of Detroit
A 1.75 AR header would make the same peak power and a bunch more under the curve.....alot better throttle response as well.
Would a 1.875 header make more power than stock manifolds....of course....its just the wrong choice for most 346 combo's, even reasonably aggressive ones with good heads/cam packages.
IMO the smarter move is to do what a few others have mentioned....get the right header now (the 1.75) and get the right header later (the 1.875).....most big inch "dream projects" take twice as long as you think (ask me how I know...LOL).
Down the road you can sell your 1.75 headers and probably recoupe a fair amount of your purchase price so the cost of ownership in the right header isnt as bad as you think and you reap the returns of having the right header every day....which will likely be alot more days than you think.
Tony
Would a 1.875 header make more power than stock manifolds....of course....its just the wrong choice for most 346 combo's, even reasonably aggressive ones with good heads/cam packages.
IMO the smarter move is to do what a few others have mentioned....get the right header now (the 1.75) and get the right header later (the 1.875).....most big inch "dream projects" take twice as long as you think (ask me how I know...LOL).
Down the road you can sell your 1.75 headers and probably recoupe a fair amount of your purchase price so the cost of ownership in the right header isnt as bad as you think and you reap the returns of having the right header every day....which will likely be alot more days than you think.
Tony
I am with Tony on this one.
Ok, tune coming tomorrow. Will let you guys know how it goes.
BTW, I just added 17x11 rears since the last dyno. Will that make enough difference to warrant putting the 17x9s back on for the dyno tune tomorrow? I've also changed the plugs, fuel filter, and doen a half *** injector cleaning so I think that may offset the heavier wheels. What are your thoughts?
BTW, I just added 17x11 rears since the last dyno. Will that make enough difference to warrant putting the 17x9s back on for the dyno tune tomorrow? I've also changed the plugs, fuel filter, and doen a half *** injector cleaning so I think that may offset the heavier wheels. What are your thoughts?
At LMR today getting tuned!! Will post the graph tonight.
There is a KEY difference - I put OE Concepts 17x11s on the rear. I know this will lower the dyno results as they are heavier than the 17x9s. Anyone know how much it will affect the numbers on a percentage basis?
I did find this:
https://ls1tech.com/forums/showthrea...ght=dyno+17x11
There is a KEY difference - I put OE Concepts 17x11s on the rear. I know this will lower the dyno results as they are heavier than the 17x9s. Anyone know how much it will affect the numbers on a percentage basis?
I did find this:
https://ls1tech.com/forums/showthrea...ght=dyno+17x11
DYNO GRAPHS HERE:
https://ls1tech.com/forums/showthrea...45#post9136045
https://ls1tech.com/forums/showthrea...45#post9136045
Tech Resident
Joined: Jan 2006
Posts: 5,117
Likes: 3
From: Philly
I'm going to post exactly what I posted in the last thread:
Originally Posted by ChocoTaco369
That's really not impressive at all IMO. You went from Mac mids to longtubes and gained virtually nothing at all. Basically, your LONGTUBES did no better than a MID-LENGTH. I think you would have gained a lot more going with a longtube.
I bet if you went with 1 3/4 QTP's, you would have gained an easy 10rwhp all over the entire curve. I've seen 1 3/4 QTP's make 10rwhp over Pacesetters, and Pacesetters will outperform Macs.
The numbers you have are very disappointing IMO, and since it wasn't even a dyno on the same day, they're virtually meaningless. I wouldn't be happy if I spent $1500 on no gain. You could have spent a lot less money and gotten a much bigger gain.
Sorry for being a buzzkill, but this is where internet legends are born and these are the threads that will cause people to make bad decisions. You went from a midlength header with a y-pipe with a terrible merge to a longtube with high velocity merge collectors and a good merge in the y-pipe and gained nothing. This thread is proof that 1 7/8 headers are a bad decision on a 346 because even with better collectors and a much better y-pipe, they can't outperform mids. Again, not trying to hurt your feelings, but I don't want to see a bunch of people buying the wrong product for their car. I feel you made the wrong decision here, at least for the short term. Unless you want to go FI on a stroker, I can't justify the cost of 1 7/8 headers, not when they can't outperform an outdated midlength header with a junk y-pipe. I think this thread is proof of what Tony Mamo had to say in the last thread.
I bet if you went with 1 3/4 QTP's, you would have gained an easy 10rwhp all over the entire curve. I've seen 1 3/4 QTP's make 10rwhp over Pacesetters, and Pacesetters will outperform Macs.
The numbers you have are very disappointing IMO, and since it wasn't even a dyno on the same day, they're virtually meaningless. I wouldn't be happy if I spent $1500 on no gain. You could have spent a lot less money and gotten a much bigger gain.
Sorry for being a buzzkill, but this is where internet legends are born and these are the threads that will cause people to make bad decisions. You went from a midlength header with a y-pipe with a terrible merge to a longtube with high velocity merge collectors and a good merge in the y-pipe and gained nothing. This thread is proof that 1 7/8 headers are a bad decision on a 346 because even with better collectors and a much better y-pipe, they can't outperform mids. Again, not trying to hurt your feelings, but I don't want to see a bunch of people buying the wrong product for their car. I feel you made the wrong decision here, at least for the short term. Unless you want to go FI on a stroker, I can't justify the cost of 1 7/8 headers, not when they can't outperform an outdated midlength header with a junk y-pipe. I think this thread is proof of what Tony Mamo had to say in the last thread.