33hotrod exhaust problems?

[FI 427]

Hi first post here, building 33 hot rod with ls chev engine. I am at the muffler, split exhaust install stage, and boy there isn't a lot of clearance from the mufflers to the floor pan! Has any one had issues with the heat issue? I can't see where I can even put a shield or wrapping on the muffs,it's so tight. I haven't put the floor pans in as of yet and wondered if anyone has a thought ? Thanks. Fi 427

[bbksv]

Yeah..we all have the same issue. There are a lot of insulation techniques..but I used lizard skin and thermo tech cool it..and it isn't bad now.

[In33anity]

On my very long list for the week before Labor Day is my plan for this issue. 1/2" rectangular tube aluminum skeleton supporting a subfloor, narrow from above the subfloor with a layer of insulation, powder coated diamond plate aluminum floor screwed in from the top. Plan is for the whole thing to drop in as a package. Will use the FFR sides, but cut out the bottom other than a 3/4" flange. Giving up a little height, but seat frames are low. Hoping the sandwich plan works! Will let you know.

[myjones]

Sock it
I plan to use a heat sock like they make for turbos and starters. They will make a sock for any size/shape muffler you have and they sell a roll of the same material in pipe sizes so I plan on
wrapping the muffs and the pipe from the firewall to where it turns up to go over the 8.8 It's a foil type wrap so it should last quite awhile under the car. Since more than one company
sells them and I'm not sure of any vendors on here that do I won't post a link to a specific one but if you do a search for turbo sock, starter sock muffler sock something will pop for ya.
HTH
Dale Hemi33

[FI 427]

Thanks, kinda what I was thinking, just a half inch would allow a blanked or shield on top of the muffs. Your idea of diamond plate makes sense and I have a sheet metal shop so it won't be a problem. Keep in touch , we can exchange pics of progress. Fi427@aol.com

[FI 427]

Thanks for the reply, I am considering getting that space above the muffs so the sock idea will be able to fit.

[esff32]

I, like others, have made heat shields. I used the rivnut as the spacer between the floor aluminum and the shield. There is enough room between the two to allow air flow for cooling.

http://i1288.photobucket.com/albums/b481/esff32/Factory%20Five%2033%20Build/c364c0b46ae10c8287116d97d9a6777f_zpsa8b36f2d.jpg (http://s1288.photobucket.com/user/esff32/media/Factory%20Five%2033%20Build/c364c0b46ae10c8287116d97d9a6777f_zpsa8b36f2d.jpg.h tml)

http://i1288.photobucket.com/albums/b481/esff32/Factory%20Five%2033%20Build/93157f3a400b0ec410e9f35b52847204_zps7a3cc428.jpg (http://s1288.photobucket.com/user/esff32/media/Factory%20Five%2033%20Build/93157f3a400b0ec410e9f35b52847204_zps7a3cc428.jpg.h tml)

[Barrel]

I used Lizard Skin on the floor panels (top and underside) and went with Boom Mat Floor and Tunnel Shield II Insulation on the underside as well. I also had my exhaust system Ceramic coated and I'm very happy with the result.

[maczter]

I am using a floor insulation under carpet and this on the mufflers...

http://www.jegs.com/i/DEI/186/010455/10002/-1

[DrPhantom]

I know little or nothing of which I speak, so feel free to tell me this response is asinine, I have thick skin.

It would seem to me that wraps and socks could pose a corrosion problem. Wet roads and normal road dirt and salts might accumulate in these materials and stay damp for long periods. This might not be so serious for aluminum panels but exhaust components, even stainless, might have shortened lives.

Tom

[erlihemi]

Tom,
yes, heat with chlorides will eat up stainless fast. Some of the wraps have a spray coating to "seal" against environmental factors. I prefer to keep the pipes and muffler unwrapped if possible and use a "layered approach". Air gaps, different shield materials, and insulation to diffuse, block, and dissipate the heat rather than contain it. Turbo guys will say otherwise but mass flow, velocity, and heat transfer when measured by the backside during prolonged idling in the taxi lane will be the ultimate constraint.

[DrPhantom]

Thanks, erlihemi. I love this site (and FFCars, too) -- so much expertise so willingly shared!
Imagine how many more FFR kits have been sold because of it.
Imagine how many more FFR kits were completed because of it.
Tom
P.S. I wonder if any auto tech schools list threads from these sites as "required reading."

[TigerBill]

I sprayed with lizard skin on underside, dynamat on inside and made heat shields like esff33. Tight clearance but just a small air gap makes a big difference.

[donshapansky]

4460044601
I did the same and you cannot feel anything abnormally hot after 20 minutes of idle time.

Don