TR4/4A Exhaust Wrapping

[bammons]

I have a new stainless steel exhaust system to go on. I have questions about the location of the exhaust pipes being very close to brake and fuel lines in places. Also the Toyota W58 transmission speedo cable comes out the right side very near the exhaust as well. I have sound/heat insulation to go on the floors inside. Also going thru the tunnel with the driveshaft I was worried about it hitting and rattling. So I have comfort and safety concerns. I hate to wrap my brand new exhaust but I was wondering if others have chosen to wrap the exhaust in select places? Am I worrying about nothing? Bruce

 

[Hamish Racing]

On my 3a I wrapped the headers and where is passed through the chassis cruciform like you to stop any rattling.
I used the stainless steel tie wraps.

 

[Sarastro]

Be careful about exhaust wrapping. Wrapping parts of the exhaust does not make the heat go away; it just causes it to be dissipated, with increased temperature, elsewhere. By all means, wrap the exhaust where appropriate, to prevent burning things that might touch it, and overheating things nearby, but mostly leave it alone.

I do understand the problem--I fried my first speedometer cable by letting it touch the exhaust near the engine, and I have a difficult exhaust rattle now, as well. So, I think a little minimal wrapping could help with both.

 

[TR Tom]

Rather than wrap the exhaust, I’ve found it’s much better to wrap the part that you are trying to protect from the heat. Lots of parts in addition to header wrap that work well for this purpose

 

[Popeye]

Rather than wrap the exhaust, I’ve found it’s much better to wrap the part that you are trying to protect from the heat. Lots of parts in addition to header wrap that work well for this purpose

Makes sense, thanks!

 

[bammons]

I guess wrapping the items I am concerned about makes sense rather than the exhaust but still would need to wrap the pipes going thru the tunnel if I have concerns about rattling. I will look for products that do that. I think I will fit up the new exhaust and see where it lies in there. My old beat up exhaust does touch in there and was a reason of concern as well as the brake and fuel lines in there. But that is how they made it and the Brit's would not be wrong?? Bruce

 

[Popeye]

I guess wrapping the items I am concerned about makes sense rather than the exhaust but still would need to wrap the pipes going thru the tunnel if I have concerns about rattling. I will look for products that do that. I think I will fit up the new exhaust and see where it lies in there. My old beat up exhaust does touch in there and was a reason of concern as well as the brake and fuel lines in there. But that is how they made it and the Brit's would not be wrong?? Bruce

The exhaust, once mounted, does not touch anything other than its mounts, and is rigid enough to not rattle against anything. I would not think wrap is needed to prevent noise.

 

[Racer-X-]

Rather than wrap the exhaust, I’ve found it’s much better to wrap the part that you are trying to protect from the heat. Lots of parts in addition to header wrap that work well for this purpose

That actually is a better approach. Thin aluminum sheet metal works great for "heat shields" and can be attached around the parts you're protecting, or it can even be attached to surround the pipe using "u-bolt" clamps on the pipe and attaching the heat shield to the ends of the u-bolts, under the nuts.

I also usually ceramic coat the inside of the header primary pipes and paint or ceramic coat the exterior. I do a similar coating inside and insulating heat resistant paint on the exhaust pipes from the header collector(s) to the first expansion point in the exhaust system, usually the muffler(s) on older cars, or the catlytic converter(s) if the vehicle is equipped with those. For coating the inside of pipes, I use the Eastwood coating, > Eastwood High Temp Internal Exhaust Coating and Nozzle < and on the outside of the pipes I usually use VHT "Flame Proof" exhaust paint.

Someone mentioned that this will move the heat further down the system, but the problem area is usually the front of the exhaust system, and the expansion in the mufflers especially provides a cooling effect that usually reduces the temperature to something acceptable for the pipes and routing beyond that.

 

[bammons]

Racer-X - I think what your saying is that my mid mount muffler under the seat area would be accumulating the most heat and that wrapping this first muffler would hurt the systems ability to dissipate heat. Seems the consensus is don't wrap unless I have no choice, address the pipes (brake, fuel and speedometer cable) that I am concerned about with products that protect them. That is fine with me as I hate to wrap a new stainless steel system and mar it's looks (and maybe efficiency. I installed the HVDA system and that does not allow me to use the standard exhaust mount at the rear of the transmission so I will have to come up with another way to hold the system before it goes into the tunnel so that it will go thru without hitting. Thanks for everybody's advice. Bruce