Two step headers and rpm range?

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Two step headers and rpm range?

Post by gregsdart » Sun Dec 02, 2018 8:03 pm

I have an rpm spread max of from 6,000rpm to a max of 7450 shift and trap rpm on the data logger, and am asking if two step headers help in a some what narrow rpm spread? Auto trans, 2.45 low 1.45 2nd, 1/1 high. 2 1/8 to 4 inch collecter currently, best of 8.77 at 153 at 3055 lbs.
1965 dodge Dart, 528 cu in wedge, 8.76 at 153 mph best. 3050 lbs

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Re: Two step headers and rpm range?

Post by exhausted » Sun Dec 02, 2018 9:19 pm

gregsdart wrote:
Sun Dec 02, 2018 8:03 pm
I have an rpm spread max of from 6,000rpm to a max of 7450 shift and trap rpm on the data logger, and am asking if two step headers help in a some what narrow rpm spread? Auto trans, 2.45 low 1.45 2nd, 1/1 high. 2 1/8 to 4 inch collecter currently, best of 8.77 at 153 at 3055 lbs.
Of Course. :D
Calvin Elston
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Matthews, NC 28104
704-443-8088
Web: www.elstonheaders.com
Blog: www.exhausting101.com

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Re: Two step headers and rpm range?

Post by GARY C » Sun Dec 02, 2018 10:35 pm

exhausted wrote:
Sun Dec 02, 2018 9:19 pm
gregsdart wrote:
Sun Dec 02, 2018 8:03 pm
I have an rpm spread max of from 6,000rpm to a max of 7450 shift and trap rpm on the data logger, and am asking if two step headers help in a some what narrow rpm spread? Auto trans, 2.45 low 1.45 2nd, 1/1 high. 2 1/8 to 4 inch collecter currently, best of 8.77 at 153 at 3055 lbs.
Of Course. :D
Calvin, I was curious if you sell software for your equations on headers, I know in past conversations you have been open and helpful but your time and knowledge is money and I well worth it.
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Re: Two step headers and rpm range?

Post by MadBill » Sun Dec 02, 2018 11:02 pm

Something else that could help a lot of guys in an appreciation of what's involved (hopefully without plundering too many of your hard-won secrets!) would be your list of essential and useful inputs for a successful header design.
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Re: Two step headers and rpm range?

Post by exhausted » Mon Dec 03, 2018 12:51 am

MadBill wrote:
Sun Dec 02, 2018 11:02 pm
Something else that could help a lot of guys in an appreciation of what's involved (hopefully without plundering too many of your hard-won secrets!) would be your list of essential and useful inputs for a successful header design.
Well, thats a tough one but it starts with a properly designed exhaust port based on what the engine needs instead of the flow bench. Do not believe I will ever see anything like that...

I have engine builders and racers call me and we can talk for hours sometimes. My number is on the web site. Leave a message and I'll try and get up with you.
I don't do simple header recomendations, I will just steer folks to software or call Burns and do a spec sheet. But that is just where you start. There is more to building a really good header than most people can understand or have the ability to do. My customers are folks who can not buy a header for their application or they want the last bit of power they can get and money is a small part of the equation. Most of the racing headers I have built over the years in many different applications have been copied pretty close and readily available from higher caliber racing header manufacturers, but they are generic pieces that run well but can be improved for a specific engine builders engines.
I will spend a little time here on that. I recently did a set for a New England Modified customer using a "spec" LS engine that Rousch-Yates puts together? (I don't know all the details). He was told they have tested the 1.75" and the 1.88" headers offered for their standard chassis's by Bea and ProFabrication. The report is there is no difference in power so customers can run whichever they want. So most racers when told that just shrug their shoulders and don't have a second thought. Well the engine sure seems to like the 1.63" headers I built for that engine and the customer was happy to spend the money and effort to get me to help him. One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that. News will get around about the headers on his car as he is one of the best cars, and soon Bea or ProFabrication will be asked to build some 1.63" headers for that chassis. and there ya go. There is a difference between building a header and buildiing one that makes more power.

Anyways, I have more time on my hands these days and I have been thinking about expanding my exhausting101 blog with more specific help for folks.

I was being tongue in cheek in responding to that post. It is possible but it is not easy or cheap and so not worth the effort for the bottom 98%. :(
Calvin Elston
Elston Exhaust Inc.
Matthews, NC 28104
704-443-8088
Web: www.elstonheaders.com
Blog: www.exhausting101.com

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Re: Two step headers and rpm range?

Post by steve cowan » Mon Dec 03, 2018 3:09 am

exhausted wrote:
Mon Dec 03, 2018 12:51 am
MadBill wrote:
Sun Dec 02, 2018 11:02 pm
Something else that could help a lot of guys in an appreciation of what's involved (hopefully without plundering too many of your hard-won secrets!) would be your list of essential and useful inputs for a successful header design.
Well, thats a tough one but it starts with a properly designed exhaust port based on what the engine needs instead of the flow bench. Do not believe I will ever see anything like that...

I have engine builders and racers call me and we can talk for hours sometimes. My number is on the web site. Leave a message and I'll try and get up with you.
I don't do simple header recomendations, I will just steer folks to software or call Burns and do a spec sheet. But that is just where you start. There is more to building a really good header than most people can understand or have the ability to do. My customers are folks who can not buy a header for their application or they want the last bit of power they can get and money is a small part of the equation. Most of the racing headers I have built over the years in many different applications have been copied pretty close and readily available from higher caliber racing header manufacturers, but they are generic pieces that run well but can be improved for a specific engine builders engines.
I will spend a little time here on that. I recently did a set for a New England Modified customer using a "spec" LS engine that Rousch-Yates puts together? (I don't know all the details). He was told they have tested the 1.75" and the 1.88" headers offered for their standard chassis's by Bea and ProFabrication. The report is there is no difference in power so customers can run whichever they want. So most racers when told that just shrug their shoulders and don't have a second thought. Well the engine sure seems to like the 1.63" headers I built for that engine and the customer was happy to spend the money and effort to get me to help him. One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that. News will get around about the headers on his car as he is one of the best cars, and soon Bea or ProFabrication will be asked to build some 1.63" headers for that chassis. and there ya go. There is a difference between building a header and buildiing one that makes more power.

Anyways, I have more time on my hands these days and I have been thinking about expanding my exhausting101 blog with more specific help for folks.

I was being tongue in cheek in responding to that post. It is possible but it is not easy or cheap and so not worth the effort for the bottom 98%. :(
Mr Elston,
i was reading some old threads where there was great conversation between yourself,proheader,900hp,i enjoy information on the tri-y header which i kinda think it is a little under estimated to the as per norm 4 into 1 deal,i will look at your 101 blog,thanks for sharing all your hard earned information over the years.
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Re: Two step headers and rpm range?

Post by digger » Mon Dec 03, 2018 4:01 am

exhausted wrote:
Mon Dec 03, 2018 12:51 am
One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that.
what about the scenario when you see the larger header make more power than something that is smaller. in particular when the smaller one isn't actually that small

say for example a 575hp engine and 1-7/8" makes more than 1-3/4"?

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Re: Two step headers and rpm range?

Post by steve cowan » Mon Dec 03, 2018 4:33 am

digger wrote:
Mon Dec 03, 2018 4:01 am
exhausted wrote:
Mon Dec 03, 2018 12:51 am
One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that.
what about the scenario when you see the larger header make more power than something that is smaller. in particular when the smaller one isn't actually that small

say for example a 575hp engine and 1-7/8" makes more than 1-3/4"?
Digger,
what size is the exhaust port exit??
i would think we need to size the header flange and primary pipe to the exhaust port exit area first,but at a guess the bigger pipe might have to turn earlier because of the bigger diameter compared to the smaller pipe diameter,but it might run deeper than that due to velocity at the exit,cam timing,reversion etc,i dont think there is a simple answer.
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Re: Two step headers and rpm range?

Post by gregsdart » Mon Dec 03, 2018 5:00 am

When i built these headers to easily get the length of 30 inch from the valve head to collecter, i came straight out of the heads as best i could and all tubes go OVER the chassis tube. That allowed at least ten inch of tube with less than about thirty degrees of bend before turning down to the collecter for six of eight tubes. The collecter is about eight inch long from the tubes to the end. I assume this info is not near enough for a good recomendation on changes and going to a two step, just wondering if there are ny serious flaws in my design.
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1965 dodge Dart, 528 cu in wedge, 8.76 at 153 mph best. 3050 lbs

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Re: Two step headers and rpm range?

Post by exhausted » Mon Dec 03, 2018 8:13 am

digger wrote:
Mon Dec 03, 2018 4:01 am
exhausted wrote:
Mon Dec 03, 2018 12:51 am
One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that.
what about the scenario when you see the larger header make more power than something that is smaller. in particular when the smaller one isn't actually that small

say for example a 575hp engine and 1-7/8" makes more than 1-3/4"?
Well you saw a difference so the rules don't apply. I would say however there is a difference racing dynos verses race cars. Once you get a header big enough to flow enough for the power level, you aren't gonna make more power by going bigger. The real beauty of a good header is making the same hp numbers while increasing the bottom end of the curve. Thats where amateurs and box headers miss the boat, you have to pay to get both. A well sorted race engine at 575 hp to me is a 1.63" header off the head, it will make a bunch more torque than your 1.88" header. It depends on what you have and what you are trying to do. :)
Calvin Elston
Elston Exhaust Inc.
Matthews, NC 28104
704-443-8088
Web: www.elstonheaders.com
Blog: www.exhausting101.com

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Re: Two step headers and rpm range?

Post by exhausted » Mon Dec 03, 2018 8:23 am

steve cowan wrote:
Mon Dec 03, 2018 3:09 am
exhausted wrote:
Mon Dec 03, 2018 12:51 am
MadBill wrote:
Sun Dec 02, 2018 11:02 pm
Something else that could help a lot of guys in an appreciation of what's involved (hopefully without plundering too many of your hard-won secrets!) would be your list of essential and useful inputs for a successful header design.
Well, thats a tough one but it starts with a properly designed exhaust port based on what the engine needs instead of the flow bench. Do not believe I will ever see anything like that...

I have engine builders and racers call me and we can talk for hours sometimes. My number is on the web site. Leave a message and I'll try and get up with you.
I don't do simple header recomendations, I will just steer folks to software or call Burns and do a spec sheet. But that is just where you start. There is more to building a really good header than most people can understand or have the ability to do. My customers are folks who can not buy a header for their application or they want the last bit of power they can get and money is a small part of the equation. Most of the racing headers I have built over the years in many different applications have been copied pretty close and readily available from higher caliber racing header manufacturers, but they are generic pieces that run well but can be improved for a specific engine builders engines.
I will spend a little time here on that. I recently did a set for a New England Modified customer using a "spec" LS engine that Rousch-Yates puts together? (I don't know all the details). He was told they have tested the 1.75" and the 1.88" headers offered for their standard chassis's by Bea and ProFabrication. The report is there is no difference in power so customers can run whichever they want. So most racers when told that just shrug their shoulders and don't have a second thought. Well the engine sure seems to like the 1.63" headers I built for that engine and the customer was happy to spend the money and effort to get me to help him. One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that. News will get around about the headers on his car as he is one of the best cars, and soon Bea or ProFabrication will be asked to build some 1.63" headers for that chassis. and there ya go. There is a difference between building a header and buildiing one that makes more power.

Anyways, I have more time on my hands these days and I have been thinking about expanding my exhausting101 blog with more specific help for folks.

I was being tongue in cheek in responding to that post. It is possible but it is not easy or cheap and so not worth the effort for the bottom 98%. :(
Mr Elston,
i was reading some old threads where there was great conversation between yourself,proheader,900hp,i enjoy information on the tri-y header which i kinda think it is a little under estimated to the as per norm 4 into 1 deal,i will look at your 101 blog,thanks for sharing all your hard earned information over the years.
Thanks Steve. That is one thing I have never gone away from. I will always want to do a 421 if the engine runs anywhere below 8-8500rpm's. I have never seen a application where a proper 421 isn't better than a proper 4into1. And don't misunderstand, I have done many 421 headers for Comp motors running past 10k, but it was because they were small engines pulling automtics or something. Heck, Warren Johnson was the first PS to go 200mph when he bolted on his 421 headers. They were chipping those cars around 5000rpm back then and the 421 made a big difference at the hit and they got more time to accelerate. :D
Calvin Elston
Elston Exhaust Inc.
Matthews, NC 28104
704-443-8088
Web: www.elstonheaders.com
Blog: www.exhausting101.com

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Re: Two step headers and rpm range?

Post by digger » Mon Dec 03, 2018 7:31 pm

exhausted wrote:
Mon Dec 03, 2018 8:13 am
digger wrote:
Mon Dec 03, 2018 4:01 am
exhausted wrote:
Mon Dec 03, 2018 12:51 am
One simple lesson to learn here, if you change headers by a entire 1/8th of an inch throughout the whole header and don't see a difference? There are two possibilities, 1) The headers are not even close to what the engine wants or 2) the engine is way off on some other part. There is power left on the table when I hear that.
what about the scenario when you see the larger header make more power than something that is smaller. in particular when the smaller one isn't actually that small

say for example a 575hp engine and 1-7/8" makes more than 1-3/4"?
Well you saw a difference so the rules don't apply. I would say however there is a difference racing dynos verses race cars. Once you get a header big enough to flow enough for the power level, you aren't gonna make more power by going bigger. The real beauty of a good header is making the same hp numbers while increasing the bottom end of the curve. Thats where amateurs and box headers miss the boat, you have to pay to get both. A well sorted race engine at 575 hp to me is a 1.63" header off the head, it will make a bunch more torque than your 1.88" header. It depends on what you have and what you are trying to do. :)
I thought you might have said that the shape of the pipes is likely not upto scratch (or length is too long) if it needs a few pipe sizes more than your guidelines to make the power. Or perhaps the speed in both cases was low enough that power difference was to do with change in area from primary to collector.


What's your view on collector size? Do you prefer to maintain velocity which on a 360* or 240* seperated system means barely much bigger than last primary step size or is it more a step change in area to generate a bigger reflection? I'm talking where you want a widepower band

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Re: Two step headers and rpm range?

Post by gregsdart » Tue Dec 04, 2018 10:21 am

I don't mind my thread going off my topic some, but would like some general input on possible gains in ET, or some idea if my headers are way out in left field. So here is a bit more info, and i know the answers are not going to be guarantees of gains, just opinions on limited info on what MIGHT be possible gains, or better to leave the headers as is. So i ask for your opionions.
4.15 stroke 4.500 bore 528 cubes, single plane large port 3x Indy Intake on ported 440-1 heads, Jones inverted flank rollercam, 284/296/114 with .870 gross intake lift, .800 exhaust. In at 110. Alky injected, 15/ compression,.
Exhaust ports on these heads are large, and the header flange required a lot of enlarging of the 2 1/8 pipes to fit. the flange,, and match the port. 2 1/8 tubes are 28 inch to the collecter from the head. No or little pinch in the collecters, about nine inch from pipe to end of collecter. I have run 8.77 at 153 at 3055 wieght, 2.45. Low gear Torqueflite with 1.45 second, 4.56 rear gear with 33 inch tall by 15 wide Goodyears. Launch at 5,000 off brake, flashes to 6,000 in low, shift at 7450 drops to 6200, 2/3 shift at 7300 drops to 6200, 7450 at stripe. So again, any idea if there may be more that say 15 hp hiding in this deal?
1965 dodge Dart, 528 cu in wedge, 8.76 at 153 mph best. 3050 lbs

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Re: Two step headers and rpm range?

Post by groberts101 » Tue Dec 04, 2018 2:53 pm

gregsdart wrote:
Tue Dec 04, 2018 10:21 am
I don't mind my thread going off my topic some, but would like some general input on possible gains in ET, or some idea if my headers are way out in left field. So here is a bit more info, and i know the answers are not going to be guarantees of gains, just opinions on limited info on what MIGHT be possible gains, or better to leave the headers as is. So i ask for your opionions.
4.15 stroke 4.500 bore 528 cubes, single plane large port 3x Indy Intake on ported 440-1 heads, Jones inverted flank rollercam, 284/296/114 with .870 gross intake lift, .800 exhaust. In at 110. Alky injected, 15/ compression,.
Exhaust ports on these heads are large, and the header flange required a lot of enlarging of the 2 1/8 pipes to fit. the flange,, and match the port. 2 1/8 tubes are 28 inch to the collecter from the head. No or little pinch in the collecters, about nine inch from pipe to end of collecter. I have run 8.77 at 153 at 3055 wieght, 2.45. Low gear Torqueflite with 1.45 second, 4.56 rear gear with 33 inch tall by 15 wide Goodyears. Launch at 5,000 off brake, flashes to 6,000 in low, shift at 7450 drops to 6200, 2/3 shift at 7300 drops to 6200, 7450 at stripe. So again, any idea if there may be more that say 15 hp hiding in this deal?
Some of these guys may know better than I but those 9" long collectors sure sound a bit short of proper secondary tuning lengths. Get that right and 15 hp is easy beans for big cubes like that.

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Re: Two step headers and rpm range?

Post by exhausted » Tue Dec 04, 2018 3:54 pm

groberts101 wrote:
Tue Dec 04, 2018 2:53 pm
gregsdart wrote:
Tue Dec 04, 2018 10:21 am
I don't mind my thread going off my topic some, but would like some general input on possible gains in ET, or some idea if my headers are way out in left field. So here is a bit more info, and i know the answers are not going to be guarantees of gains, just opinions on limited info on what MIGHT be possible gains, or better to leave the headers as is. So i ask for your opionions.
4.15 stroke 4.500 bore 528 cubes, single plane large port 3x Indy Intake on ported 440-1 heads, Jones inverted flank rollercam, 284/296/114 with .870 gross intake lift, .800 exhaust. In at 110. Alky injected, 15/ compression,.
Exhaust ports on these heads are large, and the header flange required a lot of enlarging of the 2 1/8 pipes to fit. the flange,, and match the port. 2 1/8 tubes are 28 inch to the collecter from the head. No or little pinch in the collecters, about nine inch from pipe to end of collecter. I have run 8.77 at 153 at 3055 wieght, 2.45. Low gear Torqueflite with 1.45 second, 4.56 rear gear with 33 inch tall by 15 wide Goodyears. Launch at 5,000 off brake, flashes to 6,000 in low, shift at 7450 drops to 6200, 2/3 shift at 7300 drops to 6200, 7450 at stripe. So again, any idea if there may be more that say 15 hp hiding in this deal?
Some of these guys may know better than I but those 9" long collectors sure sound a bit short of proper secondary tuning lengths. Get that right and 15 hp is easy beans for big cubes like that.
Wouldn't argue with groberts101. Wonder about the power level as I would be guessing, but injected on "alky" guessing 900-1000 or more? and straight 2.12 at that power level and length is probably not big enough. At 28" I would want to step at least once to 2.25". You didn't mention collector diameter but 3.5 isn't too large and probably should play with adding length. You could also do a spec form with Vince @ Burns stainless and see what he would recomend for a header and collector and if an area is out of wack. if it is a 1/4" smaller or more collector from what you have then I would do that also. Bet he would want to see 2.25 if not 2.375" so figure that before you invest in any collectors. :)
Calvin Elston
Elston Exhaust Inc.
Matthews, NC 28104
704-443-8088
Web: www.elstonheaders.com
Blog: www.exhausting101.com

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