type Gendy

Good work jesse

sameOciv

i want one

white92eg9

how much for 3" for a eg sedan?

Hondaen

The high temperature wil melt the aluminium if it is placed just behind the header.

How do I know ? Been there done that. Free exhaust right after the header in a tunel is insane...

onefstek

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hondaen &raquo;</TD></TR><TR><TD CLASS="quote">The high temperature wil melt the aluminium if it is placed just behind the header.

How do I know ? Been there done that. Free exhaust right after the header in a tunel is insane... </TD></TR></TABLE>

I dont' think that would happen unless your car is extremelly retarded in timing, and running relly hot.

Name: Aluminum
Symbol: Al
Atomic Number: 13
Atomic Mass: 26.981539 amu
Melting Point: 660.37 °C (933.52 K, 1220.666 °F)
Boiling Point: 2467.0 °C (2740.15 K, 4472.6 °F)
Number of Protons/Electrons: 13
Number of Neutrons: 14
Classification: Other Metals
Crystal Structure: Cubic
Density @ 293 K: 2.702 g/cm3
Color: Silver
British Spelling: Aluminium
IUPAC Spelling: Aluminium

99_GS-T

That's melting point though.

The metal can recrystallize far below that temperature.

If I'm not mistaken, you can get some pretty rapid grain growth around 380C. That will cause material to become brittle and lead to fatigue cracks.

Hondaen

Yes, thats right. The aluminium didnt exactly melt, it just collapsed due to the vibrations and heat. It clearly lose it mechanical strength bigtime before it actualy melt so beware. In a turbo car when driveing hard in summertime, i can se that **** is collapsing under you car :D

The engine is stock H22A2. Free exhaust from the header is RFL (real ******* loud) on a tunnel when vtec is engageing :D

onefstek

hmm.......dont' know what to say, I guess if anyone that had one on their car, can come up and enlighten us on how it worked out for them.

IMHO: I don't think that will be an issue if you have it start at the point where the OEM cat would have been.

80884

I won't get into this, but there are 4 or 5 people that I know of that have been running an aluminum exhaust for over a year now. One even got smashed by a man hole!! Dented, fixed the dent, and it's still on the car! Has yet to melt off or distort.

It's all in what you use and how you use it, I've seen stainless turbo manifolds crack and fall off only after a few hrs of use. Yea the alum exhaust may not last as long as a stainless exhaust but it isn't made to last...it's more for weight savings.

Have pics of this failed alum exhaust? How it was attatched to the car and to the header?

99_GS-T

I don't doubt that it works.

Just pointing out some issues with using aluminum.

I wouldn't be worried much on a drag car as the time spent at the higher temperatures would be brief. I'd be worried about crusing down the freeway for an hour with an aluminum exhaust though.

onefstek

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99_GS-T &raquo;</TD></TR><TR><TD CLASS="quote">I don't doubt that it works.

Just pointing out some issues with using aluminum.

I wouldn't be worried much on a drag car as the time spent at the higher temperatures would be brief. I'd be worried about crusing down the freeway for an hour with an aluminum exhaust though.</TD></TR></TABLE>

You fail to realize that at crusing your exhaust temps are not verry high. And the exhaust being so long, it acts as a heat sink as it disipates the heat along the whole exhaust, not just one spot.

99_GS-T

Most cars run 750+C EGTs while cruising. I don't know how you say that is not hot considering it is higher then the melting temperature of these metals.

Granted the HEAT FLOW is not high due to the mass flow being relatively low, but the temperatures are well above that of the recrystallization point.

Further more, the temperature doesn't instantly dissipate. You will have spots that are hotter then others. Also, the gas will be hotter the closer it is to the motor.

Non of this changes that fact that it makes it lighter, which is the whole point of the aluminum exhaust. Sorry for going off on a tangent about metallurgy and why aluminum exhausts might not be the best choice for a street car.

bigplansnocar

I am also curious where you found the 4" Vband set ups, i have been looking for awhile now?

Thanks.

david@didrace.com

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 99_GS-T &raquo;</TD></TR><TR><TD CLASS="quote">Most cars run 750+C EGTs while cruising.</TD></TR></TABLE>

1382*F seems a little bit high for cruising.

tony1

I think that's a realistic number at the head, but if you measured EGT's around where the cat is then they'd be a lot lower.

david@didrace.com

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tony1 &raquo;</TD></TR><TR><TD CLASS="quote">I think that's a realistic number at the head, but if you measured EGT's around where the cat is then they'd be a lot lower.</TD></TR></TABLE>

That's more or less what I was getting at. I could measure the exhaust temp anywhere I wanted to but if it's not relative to what we're talking about, what's the point (noone is making an aluminum header here... yet ).

80884

A little birdy landed on my shoulder the other day and mentioned someone making a dp out of alum just to see what happens.

One of the cars I was refering to spends a lot of time driving from AZ to NJ

But like I said, numbers don't always mean everything. Like most people on h-t that want real world proof of product results . I'd like to see real world proof of someones set up actually melting the alum exhaust or causing it to crack. When using the right material and having it setup right I don't see it happening. If for some reason your running 1300* in the exhaust at the firewall...than I belive the temps at the flange would be much higher and the engine would most likely be ready to melt, so yes that would cause the alum exhaust to melt as well when operating at that temp.

Curious...anyone ever measure EGT at the firewall area?

Pfieff

**** looks real good brotha.....Going to make one of those for the s2k for me?

onefstek

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 80884 &raquo;</TD></TR><TR><TD CLASS="quote">

Curious...anyone ever measure EGT at the firewall area?</TD></TR></TABLE>

I measured EGT's 6" away from my turbo on my 3" downpipe and it never went above 900* under boost with 12.5 : 1 A/F's. So I don't think it would be much over 500* by the time it gets to the firewall.

doodooheadfart

wow


that is absoluley BEAUTIFUL!

Fitti

great work. Nice exhaust

EM1SON

nice job
vrooom vrooom

JDMorgan

if i'm not mistaken, aluminum as we use it is an alloy. i don't think the (element) melting point above would be accurarate. i'm sure running such a large pipe helps to keep temps lower, since it lets the gasses expand. does anyone know if egt at the cat is lower on a turbo motor or not? i would think they are since alot of the heat is used by the turbo and even transfered into the intake air.

onefstek

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KraZEtEggIE &raquo;</TD></TR><TR><TD CLASS="quote">if i'm not mistaken, aluminum as we use it is an alloy. i don't think the (element) melting point above would be accurarate. </TD></TR></TABLE>

Here is a link for the properties of 6061-t6 with a melting point of 1080 - 1210 °F

http://www.matweb.com/search/S...A6016

JoJO...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Fitti &raquo;</TD></TR><TR><TD CLASS="quote">great work. Nice exhaust</TD></TR></TABLE>