What are the best practices to keep exhaust heat from escaping header pipes into engine room and thus not negatively affecting all the heat sensitive things in the vicinity of the header pipes?
I'm asking this question in the context of my Miura project but I know it has to be an issue/challenge for all mid-engine cars, some likely more than others, especially those with a V engine and 2 sets of headers.
I'm familiar with heat shields and have built/used them in other cars, e.g. my Cobra where header runs close to foot box. My primary challenge with the transverse mid-engined Miura is that the headers are so close to things like the starter, oil pan and transaxle (out of necessity due to very little space) that there's no room for the needed air gap of a heat shield to effectively work. In this situation, the heat control really needs to keep the heat from escaping from within the header tubes to be effective.
The headers are made of 304 stainless steel and are clean inside and out as there hasn't been any exhaust through them yet. I wiped the insides down with rubbing alcohol when fabricating them to remove oils prior to welding. I'm hoping to do an engine startup in the not too distant future and so now is the time to give it my best shot.
My initial plan was to ceramic coat them inside and out for heat control. In the interim, and after using CeraKote on my Cobra headers, it's clear to me that you can only realistically achieve about .001 inch thick coating using this product without it having "solvent popping" issues. "Solvent pop" occurs about 2 hours after the ceramic coating is sprayed on and is in essence a bubbling or blistering of the material where it has been applied too thick. How much heat control can be achieved with a .001 thick coating (.002 if used inside and out)? Yes, I contacted CeraKote technical support and they repeatedly told me the product cannot be applied greater than .001 thick or solvent pop will likely occur.
So my question out to those with experience in exhaust header heat control is what have you found to work best?
I'm asking this question in the context of my Miura project but I know it has to be an issue/challenge for all mid-engine cars, some likely more than others, especially those with a V engine and 2 sets of headers.
I'm familiar with heat shields and have built/used them in other cars, e.g. my Cobra where header runs close to foot box. My primary challenge with the transverse mid-engined Miura is that the headers are so close to things like the starter, oil pan and transaxle (out of necessity due to very little space) that there's no room for the needed air gap of a heat shield to effectively work. In this situation, the heat control really needs to keep the heat from escaping from within the header tubes to be effective.
The headers are made of 304 stainless steel and are clean inside and out as there hasn't been any exhaust through them yet. I wiped the insides down with rubbing alcohol when fabricating them to remove oils prior to welding. I'm hoping to do an engine startup in the not too distant future and so now is the time to give it my best shot.
My initial plan was to ceramic coat them inside and out for heat control. In the interim, and after using CeraKote on my Cobra headers, it's clear to me that you can only realistically achieve about .001 inch thick coating using this product without it having "solvent popping" issues. "Solvent pop" occurs about 2 hours after the ceramic coating is sprayed on and is in essence a bubbling or blistering of the material where it has been applied too thick. How much heat control can be achieved with a .001 thick coating (.002 if used inside and out)? Yes, I contacted CeraKote technical support and they repeatedly told me the product cannot be applied greater than .001 thick or solvent pop will likely occur.
So my question out to those with experience in exhaust header heat control is what have you found to work best?
