Shorty Headers
- Thread starter Fubar
- Start date
HeritageBruce
GT Owner
Check out this OEM BMW M3 exhaust. What a work of art on a car that costs "only" in the 60's.
http://blogs.edmunds.com/straightline/2007/03/details-on-the-next-m3s-v8.html
A little off topic here, is there any American made car with this type of exhaust headers right from the factory?
http://blogs.edmunds.com/straightline/2007/03/details-on-the-next-m3s-v8.html
A little off topic here, is there any American made car with this type of exhaust headers right from the factory?
Beach-GT
GT Owner
![M3-engine-parts[1].430.jpg](/forums/data/attachments/6/6063-38ddef898b39c0eb188c6199cd64085d.jpg)
- Aug 25, 2006
- 4,436
Here I go head first into the “Snake Pitt”
I was asked if I would comment on the posted measured horse power gains with Fubar’s gal and it is with some reluctance I do so and “only” after chatting at length with Shawn the fellow responsible for the creation of the headers and the associated dyno pull data as present.
Let me begin by sharing that I have chatted with Shawn several times over the past few weeks and have in fact agreed to work with him on a project.
Having shared this let me once again share my opinion on headers (whether they are long or short) on these gals. I personally enjoy the eye candy element of them; they look IMO stunning on the gals particularly since the heart of the gal is so visible. Then add to this being an old hot-rodder I also enjoy the music that headers create; now I do not mean tail pipe noise but rather the gal firing within the tubes. Now do headers allow for more power to be produced by these gal’s; the simple answer is no however the long answer would include minimal at best. Headers on a forced induction heart do not have the same effect as they can have on a normally aspirated heart and even more so headers when designed for power are done so for a particular point in time; meaning RPM/load range and seldom if even afford a linear growth in power throughout the entire RPM range; in fact headers can actually rob power from one area as they facilitate the addition of it in another.
In any case I care not to ramble and even more so I do not wish to diminish Fubar’s excitement but rather bring this issue back to center.
I received the run files from Shawn and reviewed them and near as I can tell there was little if any gain as the direct result of these truly very cool headers. Now before everyone goes; what the heck let me explain.
When Fubar’s gal was initially placed on the dyno Shawn shared that the A/F numbers appears to be skewed; as Shawn shared with me either the tuning was way off or there was a leak in the exhaust system. Once the new system was installed the A/F numbers came into line and on paper she appeared much happier. Furthermore the before and after dyno logs are nearly identical albeit the later show a modest growth in HP however there is no deviation in the points at which the power is produced but rather a consistent increase from one end to the other.
After chatting with Shawn today we both agree that the increase was likely not as the result of the headers but rather because she is;
1. Running better with no vacuum/exhaust leaks
2. Simply a different day on the same dyno
3. A variable in how/when the pull was initiated; coolant temperature, air temperature, humidity, etc.
I was also told by Shawn that of the dyno pulls that were made she saw a measured (on paper) growth in horse power when her coolant temperature was at or below 185F range however as soon as the temperature increased the power levels diminished to the point where there were no measureable gains; FYI these results are normal.
In any case she runs very strong, the headers look stunning, and IMO the headers are a very nice visual and audible improvement for his gal.
So should you purchase and install headers; as a motor-head I say yes however you need to determine if the value for what you will see and hear is equal to or of greater than that which you have to exchange for them.
Takes care
Shadowman
I was asked if I would comment on the posted measured horse power gains with Fubar’s gal and it is with some reluctance I do so and “only” after chatting at length with Shawn the fellow responsible for the creation of the headers and the associated dyno pull data as present.
Let me begin by sharing that I have chatted with Shawn several times over the past few weeks and have in fact agreed to work with him on a project.
Having shared this let me once again share my opinion on headers (whether they are long or short) on these gals. I personally enjoy the eye candy element of them; they look IMO stunning on the gals particularly since the heart of the gal is so visible. Then add to this being an old hot-rodder I also enjoy the music that headers create; now I do not mean tail pipe noise but rather the gal firing within the tubes. Now do headers allow for more power to be produced by these gal’s; the simple answer is no however the long answer would include minimal at best. Headers on a forced induction heart do not have the same effect as they can have on a normally aspirated heart and even more so headers when designed for power are done so for a particular point in time; meaning RPM/load range and seldom if even afford a linear growth in power throughout the entire RPM range; in fact headers can actually rob power from one area as they facilitate the addition of it in another.
In any case I care not to ramble and even more so I do not wish to diminish Fubar’s excitement but rather bring this issue back to center.
I received the run files from Shawn and reviewed them and near as I can tell there was little if any gain as the direct result of these truly very cool headers. Now before everyone goes; what the heck let me explain.
When Fubar’s gal was initially placed on the dyno Shawn shared that the A/F numbers appears to be skewed; as Shawn shared with me either the tuning was way off or there was a leak in the exhaust system. Once the new system was installed the A/F numbers came into line and on paper she appeared much happier. Furthermore the before and after dyno logs are nearly identical albeit the later show a modest growth in HP however there is no deviation in the points at which the power is produced but rather a consistent increase from one end to the other.
After chatting with Shawn today we both agree that the increase was likely not as the result of the headers but rather because she is;
1. Running better with no vacuum/exhaust leaks
2. Simply a different day on the same dyno
3. A variable in how/when the pull was initiated; coolant temperature, air temperature, humidity, etc.
I was also told by Shawn that of the dyno pulls that were made she saw a measured (on paper) growth in horse power when her coolant temperature was at or below 185F range however as soon as the temperature increased the power levels diminished to the point where there were no measureable gains; FYI these results are normal.
In any case she runs very strong, the headers look stunning, and IMO the headers are a very nice visual and audible improvement for his gal.
So should you purchase and install headers; as a motor-head I say yes however you need to determine if the value for what you will see and hear is equal to or of greater than that which you have to exchange for them.
Takes care
Shadowman
beauty for the beast
The stock hunk of iron with a wrinkled metal heat shield bolted to it is UGLY. Really UGLY! If they were hidden from view it might be acceptable (like on the Italian cars). Tubular headers are needed on the GT badly. It's like having a beautiful painting in a cheesy plastic frame. The GT engine is a work of art that deserves to have tubular headers.
Ed
Fubar - right on. Your black headers & exhaust look killer. Great project.
The stock hunk of iron with a wrinkled metal heat shield bolted to it is UGLY. Really UGLY! If they were hidden from view it might be acceptable (like on the Italian cars). Tubular headers are needed on the GT badly. It's like having a beautiful painting in a cheesy plastic frame. The GT engine is a work of art that deserves to have tubular headers.
Ed
Fubar - right on. Your black headers & exhaust look killer. Great project.
Thank you for the kind words Dr. Sims.
Shadowman, I appreciate you taking the time to demystify the power gain. As I posted earlier, I did not expect a noticeable difference and the results Shawn found were surprising. It is certainly much cooler now than when I initially ran the car but I thought the machine would correct for that type of error. I'm not sure what humidity looked like when the baseline was done. It's just a paper race anyway... not worth the tree pulp it's printed on.
No matter, I am not encouraging anyone to buy these things. They were strictly for my benefit. The project was intended to meet my specific needs and has exceeded my expectations.
Shadowman, I appreciate you taking the time to demystify the power gain. As I posted earlier, I did not expect a noticeable difference and the results Shawn found were surprising. It is certainly much cooler now than when I initially ran the car but I thought the machine would correct for that type of error. I'm not sure what humidity looked like when the baseline was done. It's just a paper race anyway... not worth the tree pulp it's printed on.
No matter, I am not encouraging anyone to buy these things. They were strictly for my benefit. The project was intended to meet my specific needs and has exceeded my expectations.
Indy GT
Yea, I got one...too
Mark (Chip and others in the group buy) congratulation on a VERY cool system! The eye-candy aspect is unquestioned and really complements the true asthetic beauty our engines possess. The interchangeability aspect with the OEM components is also a great benefit for those who occassionally track their car.
But I agree 100 percent with Shadowman (and BlackIce). the performance gains are most likely from the A/F alteration due to the OEM manifold leak prior to installing the shorty headers. The OEM cast iron manifolds may not look attractive to some, but actually scavenage the engine quite well and achieve the other NHV targets the car had to have.
If complementing the "look" of the engine compartment and the sound of the engine, headers are a fine addition. Just understand that most probably that is what you are paying for. Again, congrats Mark for the fine addition to your car and thanks for the numerous assembly/fabrication pictures in the post. First rate!!
But I agree 100 percent with Shadowman (and BlackIce). the performance gains are most likely from the A/F alteration due to the OEM manifold leak prior to installing the shorty headers. The OEM cast iron manifolds may not look attractive to some, but actually scavenage the engine quite well and achieve the other NHV targets the car had to have.
If complementing the "look" of the engine compartment and the sound of the engine, headers are a fine addition. Just understand that most probably that is what you are paying for. Again, congrats Mark for the fine addition to your car and thanks for the numerous assembly/fabrication pictures in the post. First rate!!
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