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Discussion Starter #1
Hi,

Just installed the quicksilver ex. manifold and "race cat". The header is heat wrapped. Followed the OEM heat shield location and wrapped the U pipe from Cat back to the muffler.

My exhaust glows RED HOT after med - hard driving. everything from the cat to the bolt on secondary O2 through up to the muffler. Must be quite a site at night from cars behind me.

Is there any cause for concern?

(note all heat shields are in with extra heat reflective materials around the car area. Only the rear side of the heat shield has been chopped.)

it's really hot back there, so hot my lic.plate lights were melting, have had to relocate to middle. Just took a test drive and think it's still too hot for the light. Will need to find another solution, any suggestions here?







thnx
 

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Discussion Starter #3
I don't think its normal for your exhaust to get that hot under normal driving. I think something is wrong.
like?

car should be running normal. No CEL light, nothing out of order.

may be the muffler design is over restrictive. it's something my friend and I made. 2 baffle plates, 3 sections... pretty standard.
 

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way back in may last year my car went all wacky! mis firing and stuff. i was driving a bucking bull! any way with all the funny stuff, gas was everywhere in my exhaust., my cat was silly hot. , i had flames shotting out the back. anyway when i did finally pull over i opened the boot, i was aghast, my cat was red. as red as molten metal.

the after math, i melted the cat and stage 2. and lucky i did not have the car go up in flames.

no cel....

ive done quite a few group drives, not once was i behind another lotus that had glowing bits.

you may want to have it looked at, based on my experience, i would. sorry i cant add more
 

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Yea - doesn't sound right.

I have Arqray Single Tip and a NA Exige. I don't have any of the heat shield stuff on and have heat wrap on just before the can.

Mine gets hot, but nothing like you have described. No worries on melting anything.
 

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Overly rich mixture and way too retarded timing? I dunno what the cause is, but it sounds dangerous and you should throw all resources into solving the problem asap.

xtn
 

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Discussion Starter #14
Could it be a clogged cat? Have you been running any leaded race fuel? Leaded gas will clog a cat.
Only use shell 97 unleaded. Cat is new.

Thanks for all the inputs guys. Wouldn't want a car b q as fishguy so kindly suggested.:cool:

My guess is its the muffler design, or boosted lotus's are like this.

Anyone else have a turbo or SC car with heat wrapped after market manifold /cat experienced this?
 

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Discussion Starter #15
A home made muffler? I would start there.
Our specs were given to the factory, we just welded the tips on.

I'll have to do an online crash course on muffler design today. My guess is the first baffle inside the muffler is too close to the inlet or that the channels inside don't flow well enough to move the heat.
 

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There has to be a way to flow test exhausts. I've never dug into it before but a shop should be able to. As long as your new exhaust flows as good or better than the stock unit you should be fine. They have to be able to calculate back pressure numbers somehow...

You could also look at using a high temp coating such as what polydyn uses and coat your exhaust too. That will keep the heat in until it exits the tip. Of course that would be quite a bit more heat exiting...

Before any car-b-q's happen can somone take a pic at night? :) I've seen glowing rotors and turbo's before. But never a muffler.
 

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Discussion Starter #17
Before any car-b-q's happen can somone take a pic at night? :) I've seen glowing rotors and turbo's before. But never a muffler.
LOL I'll take one tonight. I want a photo of it too...

Drove to work today, like a normal law abiding person. No glowing.
 

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When looking at your exhaust system, are you able to see any particular area that seems to be glowing hotter that the rest? Can you determine the point(s) that begin to glow first? Any access to high-temp thermal imaging equipment?

xtn
 

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Discussion Starter #20
When looking at your exhaust system, are you able to see any particular area that seems to be glowing hotter that the rest? Can you determine the point(s) that begin to glow first? Any access to high-temp thermal imaging equipment?

xtn
i do have a infra red temp gauge. Cars cooled down a bit but when I took readings, the hot spot was the U bend (taken off secondary sensor), however that's to be expected since it's wrapped in that area. The hot spots are clearly visible to the naked eye with the absence of ambient light.

The manifold is wrapped entirely. The cat/Ubend pipe, Heat wrapping starts at exit end of cat up until the muffler joint (same like OEM foil stuff).

Im not sure where it heats first but the heat recedes from muffler and works it's way back towards the cat. Im pretty sure the hottest point would be the second at the cat, and first at the Ubend where there's high heat friction.

clearly something is not right, back to drawing board with the muffler design. too much back pressure, not enough flow is my guess...

I tried to take pics but with the flash, the glowing is not visible, with out the flash, phone camera is not able to capture. Not going to try and induce anymore glowing, as cool as it may looks... :p

thanks for inputs everyone.
 
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