How much will I gain with results
1 3/4 tsp to 1 7/8 tsp headers with the edition of a 3 to 4 flowmaster merge on the y pipe. Made the same power but it ran a little richer.
Same dyno and run conditions were almost identical.
Same dyno and run conditions were almost identical.
Last edited by 1 Slow WS6; Oct 29, 2014 at 06:42 PM.
i dont mean to be a dick but this doesnt prove a damn thing. its been well documented larger headers pick up power.... bring the afr up to where the old one is and you will make more power no doubt. until that happens this comparison doesnt mean a thing
I will personally say that the FM merge helped my car (regardless of a dyno number) gain a noticable amount of power. The merge in my Pacesetter ORY was the worst I've ever seen
This was from a conversation I had with my tuner tonight...
Feel free to quote me. It's a prefect example of a combo not needing the additional airflow where you increased the pipe size. It's the same as putting a larger throttle body on a motor that can't benefit from it. It doesn't mean it's going to automatically make more power. Even if you leaned it out it will not pick up substantially and what it does pickup you can't automatically attribute to the headers.
My advice is get a new tuner. Why didnt he retune afr? Installing a new part and not correcting afr makes comparisons useless. Thats like putting headers on a car in the 1st place and saying they only picked up 10 hp because leaning out the afr wouldnt increase power.
Bolt on cars including my cam only one pick up power all the time with 1-7/8 headers. With 510whp and a 383 no doubt you will pickup power with a better tune. Your afr looks to be around 12.3 and the other is around 13. 13-13.2:1 is best power 12.5 is borderline rich. I'd be willing to bet there's 10 hp there no problem. Its simply not an apples to apples thing if you dont correct the tune. I dont see how correcting the afr to what is was before would make the gains unattributable if anything that evens the playing field and thus would actually show the benefits of the larger primaries.
Bolt on cars including my cam only one pick up power all the time with 1-7/8 headers. With 510whp and a 383 no doubt you will pickup power with a better tune. Your afr looks to be around 12.3 and the other is around 13. 13-13.2:1 is best power 12.5 is borderline rich. I'd be willing to bet there's 10 hp there no problem. Its simply not an apples to apples thing if you dont correct the tune. I dont see how correcting the afr to what is was before would make the gains unattributable if anything that evens the playing field and thus would actually show the benefits of the larger primaries.
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I agree the tune needs to be adjusted. But VE took a hit. If this is a MAF tune, it'll work it's self out. If SD it wont.
What I got from this is that the larger headers reduced VE. Same amount of fuel going in, but less air. So the smaller headers had better velocities, therefore better scavenging.
Leaning it out will help a bit, but it's still moving less air.
It's been well documented that larger headers don't always mean more horsepower. In many cases you can lose power, especially at lower engine RPMs due to lower exhaust gas velocities.
What I got from this is that the larger headers reduced VE. Same amount of fuel going in, but less air. So the smaller headers had better velocities, therefore better scavenging.
Leaning it out will help a bit, but it's still moving less air.
It's been well documented that larger headers don't always mean more horsepower. In many cases you can lose power, especially at lower engine RPMs due to lower exhaust gas velocities.
My advice is get a new tuner. Why didnt he retune afr? Installing a new part and not correcting afr makes comparisons useless. Thats like putting headers on a car in the 1st place and saying they only picked up 10 hp because leaning out the afr wouldnt increase power.
Bolt on cars including my cam only one pick up power all the time with 1-7/8 headers. With 510whp and a 383 no doubt you will pickup power with a better tune. Your afr looks to be around 12.3 and the other is around 13. 13-13.2:1 is best power 12.5 is borderline rich. I'd be willing to bet there's 10 hp there no problem. Its simply not an apples to apples thing if you dont correct the tune. I dont see how correcting the afr to what is was before would make the gains unattributable if anything that evens the playing field and thus would actually show the benefits of the larger primaries.
Bolt on cars including my cam only one pick up power all the time with 1-7/8 headers. With 510whp and a 383 no doubt you will pickup power with a better tune. Your afr looks to be around 12.3 and the other is around 13. 13-13.2:1 is best power 12.5 is borderline rich. I'd be willing to bet there's 10 hp there no problem. Its simply not an apples to apples thing if you dont correct the tune. I dont see how correcting the afr to what is was before would make the gains unattributable if anything that evens the playing field and thus would actually show the benefits of the larger primaries.
Last edited by 1 Slow WS6; Oct 30, 2014 at 06:27 AM.
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I agree the tune needs to be adjusted. But VE took a hit. If this is a MAF tune, it'll work it's self out. If SD it wont.
What I got from this is that the larger headers reduced VE. Same amount of fuel going in, but less air. So the smaller headers had better velocities, therefore better scavenging.
Leaning it out will help a bit, but it's still moving less air.
It's been well documented that larger headers don't always mean more horsepower. In many cases you can lose power, especially at lower engine RPMs due to lower exhaust gas velocities.
What I got from this is that the larger headers reduced VE. Same amount of fuel going in, but less air. So the smaller headers had better velocities, therefore better scavenging.
Leaning it out will help a bit, but it's still moving less air.
It's been well documented that larger headers don't always mean more horsepower. In many cases you can lose power, especially at lower engine RPMs due to lower exhaust gas velocities.
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Verdad Gallardo TECH Addict
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It really depends on your current build. At your power you likely won't pick up anything with larger primaries. I was looking for 1-5/8" primaries for my build, but I found a great deal on ceramic plated 1-3/4". The 1-5/8 LT's would've been custom and way too much money to justify.
the engine isnt moving less air.... the header are just capable of flowing more. 1-7/8" headers arent large enough to cause a big drop in velocity. i gained 10-12hp throughout with my swap and that was on a stock ls6 long block.
plenty of people gain power with larger headers, in fact this is the first time ive seen them not. However i still dont see how all of you are taking this as gospel. He dropped from 13.0 afr to ~12.3 thats a huge difference in terms of power. the maf will not make up for that change. the engine is now moving more air so it will throw the calibration off a bit. the ve table isnt used at wot so that has nothing to do with the dyno graph
plenty of people gain power with larger headers, in fact this is the first time ive seen them not. However i still dont see how all of you are taking this as gospel. He dropped from 13.0 afr to ~12.3 thats a huge difference in terms of power. the maf will not make up for that change. the engine is now moving more air so it will throw the calibration off a bit. the ve table isnt used at wot so that has nothing to do with the dyno graph
Your tuner is dead wrong. If you leaned it out to where it should be, and it picked up power, it would be 100% from the benefit of the additional exhaust flow.
you guys are also forgetting he also changed to a better merge which everyone claims is so special. even if it gets leaned out and picks up 10 or more rw,how much was from the bigger primaries and how much was from the better merge ? more often than not, real world gains on a mild build it's a wash. just my $.02
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It really depends on your current build. At your power you likely won't pick up anything with larger primaries. I was looking for 1-5/8" primaries for my build, but I found a great deal on ceramic plated 1-3/4". The 1-5/8 LT's would've been custom and way too much money to justify.
also he changed the merge to a large one. if he had the normal tsp one on there the merge was already pretty good. people bitch about the pacesetter or old kooks merge which were just shitty.
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the engine isnt moving less air.... the header are just capable of flowing more. 1-7/8" headers arent large enough to cause a big drop in velocity. i gained 10-12hp throughout with my swap and that was on a stock ls6 long block.
plenty of people gain power with larger headers, in fact this is the first time ive seen them not. However i still dont see how all of you are taking this as gospel. He dropped from 13.0 afr to ~12.3 thats a huge difference in terms of power. the maf will not make up for that change. the engine is now moving more air so it will throw the calibration off a bit. the ve table isnt used at wot so that has nothing to do with the dyno graph
plenty of people gain power with larger headers, in fact this is the first time ive seen them not. However i still dont see how all of you are taking this as gospel. He dropped from 13.0 afr to ~12.3 thats a huge difference in terms of power. the maf will not make up for that change. the engine is now moving more air so it will throw the calibration off a bit. the ve table isnt used at wot so that has nothing to do with the dyno graph
Here's more links. Sanderson Headers. Headers By Ed.
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ya this one got me lol... if he puts the afr back to where it was how could that not be a direct correlation to the additional exhaust flow.
also he changed the merge to a large one. if he had the normal tsp one on there the merge was already pretty good. people bitch about the pacesetter or old kooks merge which were just shitty.
also he changed the merge to a large one. if he had the normal tsp one on there the merge was already pretty good. people bitch about the pacesetter or old kooks merge which were just shitty.
To make more power you either need to increase efficiency or use more fuel and air. It looks like he's using less fuel and air, but increased efficiency and will end up where he left off with nothing but money lost in the process.
ya this one got me lol... if he puts the afr back to where it was how could that not be a direct correlation to the additional exhaust flow.
also he changed the merge to a large one. if he had the normal tsp one on there the merge was already pretty good. people bitch about the pacesetter or old kooks merge which were just shitty.
also he changed the merge to a large one. if he had the normal tsp one on there the merge was already pretty good. people bitch about the pacesetter or old kooks merge which were just shitty.
If he's pulling fuel to lean it out, it's moving less air. He can lean it out and gain some power back, but it won't be a lot of power he'll gain. There's more going on here, but the jist of it is it's moving less air.
To make more power you either need to increase efficiency or use more fuel and air. It looks like he's using less fuel and air, but increased efficiency and will end up where he left off with nothing but money lost in the process.
To make more power you either need to increase efficiency or use more fuel and air. It looks like he's using less fuel and air, but increased efficiency and will end up where he left off with nothing but money lost in the process.
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Well that's always a good thing. With no real loss in power, it allows you to grow without hurting you in future mods. Plus now you know your engine is more efficient.
I see where you guys are getting at where if the car picked up efficiency and put the same amount of fuel in, then yes it would run lean. Correct. But what I am getting at more, is that you are running off of pure MAF at 4000rpm and above (Taking that you aren't tuned in speed density), so, if the engine was more efficient, it would pull in slightly more air. So your car may have hit new MAF cells that maybe were not hit in previous tuning, so they could be off. Which could result in this rich condition. Hell some tuners even sometimes put this in tunes as a safety measure to ensure the car would not go lean, if it ever were to hit higher airflow values.
But regardless like I said before, the car was tuned before. So if we fixed this rich condition, and in effect the car picked up power, how would that not be because of the benefit of new exhaust? Where else would it have got this new power from?
But regardless like I said before, the car was tuned before. So if we fixed this rich condition, and in effect the car picked up power, how would that not be because of the benefit of new exhaust? Where else would it have got this new power from?