Header Question

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hawkwind
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Re: Header Question

Post by hawkwind » Fri Jun 22, 2012 4:51 pm

Ok we have 2 trains of thought happening here .....1.tuned length headers and there benifits & 2.taking the exhaust and pumping it behind the vehicle......interesting .... one (tuned length headers) is proven to increase the performance of an engine (verified data)....two in theory at least dumping the exhaust at the rear may have benifits??? does anyone have verifiable numbers of the net benifit/gain to drag reduction. so I ask is it worth the power loss from a tuned header setup to extend the exhaust system to the rear of the car/bike ? or for a turbo, does running a long exhaust system to the back have more benifits than the extra back pressure created in doing so ...I will ignore for the present the extra drawbacks of getting an exhaust pipe back there ......is it just another fad or is there real proof with repeatable data that the benifits out weigh the costs ?
Gary #282
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Dr Goggles
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Re: Header Question

Post by Dr Goggles » Fri Jun 22, 2012 5:46 pm

Have a read of the stuff on the link I posted on the previous page and make your own decisions Gary.......speed costs.
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RGV
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Re: Header Question

Post by RGV » Fri Jun 22, 2012 6:02 pm

Ive seen a video of a top fuel rail blowing off a set of headers and going into a barrel roll. Apparently the thrust from the exhaust blew the car over.

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JonB
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Re: Header Question

Post by JonB » Fri Jun 22, 2012 6:48 pm

Thanks Chris - that is what I was hoping you would say.

Cheers
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ben james
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Re: Header Question

Post by ben james » Fri Jun 22, 2012 7:56 pm

Dr Goggles wrote:
ben james wrote:1./ The exhaust gases are cooling rapidly, that means they are shrinking, that is an excellent way to "de-energize" the wake , it works kind of like a dampener. DAMPER :roll:

.....back to the rear exiting exhaust ... is there really enough exhaust mass or volume to make any difference at all .... considering the overall amount of air being displaced ??? I personally believe it will only have an effect on streamliners and then only a small net gain ... but I could be wrong.
I think some 4 cylinder top fuel motorcycle teams have some data about exhaust effect.
Ben
I think you're trying to have your unleavened bread and eat it too Benny,.......get a Webster's up ya. :wink: :wink:
there ya go with your big words again,
i don't know what unleavened means,
but i'm gunna look it up & do a real witty comeback i am. :?
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BOB ELLIS
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Re: Header Question

Post by BOB ELLIS » Fri Jun 22, 2012 9:42 pm

Ben , hurry up with the unleavened explaination !! We're getting " exhausted" waiting to find out what it means,

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Dr Goggles
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Re: Header Question

Post by Dr Goggles » Fri Jun 22, 2012 10:18 pm

OK Bob, turns out Benny has an ongoing argument with a yank he works with about damper/dampener....if you ask me damper is like bread, without yeast.....bread without yeast is said to be "unleavened"...it doesn't rise.


Now. Did anyone read any of the stuff that Superford317 posted on the landracing link that I posted?.......You door car guys might have noticed that Michael leFevers posted a pick of their Firebird that was the 300mph car......

It isn't something you can condense into a one word answer this stuff. As Chris mentioned he's had time to think, and has reconsidered a few lomg held ideas. It never hurts to go back to basics and think about what we are trying to do. I'm trying to do it now..............
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

hawkwind
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Re: Header Question

Post by hawkwind » Sat Jun 23, 2012 11:19 am

Quote" Now. Did anyone read any of the stuff that Superford317 posted on the landracing link that I posted?......."" end quote ....... sure did, all very interesting and informative :) BUT!!! :shock: ........conclusion WTF has any of that realistically got to do with backyard builders......I will watch closely as those with racing budgets the size of the US debt implement any of it into a practical solution then copy the stuff that works :wink: ......in the meantime I will continue building the born again fleabay special ....racing costs thank acura for China.
Vehicle......................A new creation.
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JonB
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Re: Header Question

Post by JonB » Sat Jun 23, 2012 11:39 am

Racing does cost.

Components cost money.
Innovation, design, fit and finish cost research, care factor and attention to detail.

If scratch building a component in this discussion an exhaust the $ cost between a set of zoomies and a tuned set of tuned length pipes (non dyno tested) exiting where you think you may pick up some advantage is negligible in the total build cost.

YOMV
jon
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Dr Goggles
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Re: Header Question

Post by Dr Goggles » Sat Jun 23, 2012 11:46 am

Aerodynamics are free, and they don't wear out or break.
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

penny
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Re: Header Question

Post by penny » Sat Jun 23, 2012 1:07 pm

Vortex Generators , Nebulus therom liner is long and tiny built by an expert and i think it is about as high as my knees . It has and uses Vortex Generators at the back to further enhance the air leaving at the back . I dont think that i have seen votex generators on a vehicle at our lake . There was some on a vehicle at tailem bend but they arn t the real deal .
glengowrie annexe of the Institute of Backyard Studies

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gennyshovel
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Re: Header Question

Post by gennyshovel » Sat Jun 23, 2012 1:35 pm

I stumbled across this a while back after watching a show on TV about the Spitfire, and how they gained thrust from heat generated by the engine.

http://warbirdsforum.com/showthread.php?t=5515
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grumm441
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Re: Header Question

Post by grumm441 » Sat Jun 23, 2012 4:00 pm

Dr Goggles wrote:Aerodynamics are free, and they don't wear out or break.
You're not a bike guy, are you
G
They make it
I make it work

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JonB
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Re: Header Question

Post by JonB » Sat Jun 23, 2012 5:42 pm

grumm441 wrote:
Dr Goggles wrote:Aerodynamics are free, and they don't wear out or break.
You're not a bike guy, are you
G
Why? Cos he can spel Airodinamiks propa and uses punchyouassian?
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Dr Goggles
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Re: Header Question

Post by Dr Goggles » Wed Jun 27, 2012 10:50 am

grumm441 wrote:
Dr Goggles wrote:Aerodynamics are free, and they don't wear out or break.
You're not a bike guy, are you
G
guy? isn't your spell check working properly?
...few understand what I'm trying to do , but they vastly outnumber those who understand why..

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