Exhaust gas temps??

[Ryneito]

I recently put a ESP championship ported 30.5cc head kit in my XB. Along with a wt990, a 1" Mani. and a km pipe. She runs great and was very easy to tune but I'm having one minor problem. I keep melting my silicone coupler on the exhaust. I bought some high quality high temp 4ply hose. Same stuff some other members run with no problem. Im kind of lost on the matter since I shouldn't be melting this hose. Any ideas on why it would running so hot? My tune is good. Little on the rich side. Plug color is nice brown color...

 

[Guest]

How much of the coupling ( length ) is exposed if any to the hot exhaust gas?

On my modded pipe I only have about 1/4 inch between the sections where the tube gets exposed to the exhaust.

 

[Ryneito]

Its about 3/4 of an inch gap between header pipe and pipe to the rest of the exhaust. The silicone is melting where I clamp it to the pipe. Do I want the smallest gap possible there? If so I can weld some more pipe onto the header..

 

[andyken]

I found strong zip tie/wire ties work better than hose clamps, Also so you could just put a space filler pipe in there, and not weld it..?

 

[Ryneito]

I thought about the filler piece too. Stuff it inside the coupler and leave enough overhang to clamp onto header and pipe.

So does it sound like I have to big of a gap between header and pipe and that's causing the melting??

 

[andyken]

I thought about the filler piece too. Stuff it inside the coupler and leave enough overhang to clamp onto header and pipe.So does it sound like I have to big of a gap between header and pipe and that's causing the melting??

Sounds like your tune is ok, maybe richen a bit and add the pipe spacer. When I used hose clamps, they cut thru the coupling, even on nitro rigs.

Do you have a temp gun?

Maybe you could temp the header and motor to see if it's running hotter than normal?

 

[Guest]

The best fix IMO is to extend the header. Are you using an exhaust port? If not I would recommend installing one. This will also close the gap between the header and pipe. It will assist in cooling the exhaust gasses a bit.

 

[Ryneito]

If an exhaust port is the finned aluminum spacer that mounts between the header and head then Yes I'm running one if those.

I think your right RCdad, I think I need more pipe off the header.