My 85 Ram50 has the CAT connected directly to the manifold and that is where all of the heat shielding is. I want to put one on after a header. What is the best location? How do I heat shield around it?
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My 85 Ram50 has the CAT connected directly to the manifold and that is where all of the heat shielding is. I want to put one on after a header. What is the best location? How do I heat shield around it?
2 observations - do you actually need one for emissions/inspections and put it wherever the shop can fit it without causing clearance issues (maybe under the truck bed where there's some space). The early type of catalytic converter is obsolete (2 way converters) and CATs only work when your engine is running at it's optimum AFR. It's potentially an expensive component to add to an exhaust system. Are you going to run a bigger diameter exhaust to match the headers?
To have a local shop work on it there has to be a CAT since it came with one new. I wanted one since I kind of like the planet I live on and every little bit counts. I've seen pictures of the header clearance underneath and it is very tight to the cab. I could probably put it near the tail shaft of the trans. How would I shield it and what with?
A lot of CATs come with heat shielding already on them as part of the assembly. Have a look online and see what is around. And this is part of the reason why I recommended the CAT be put further back from the cabin as they get damned hot, You could probably get away with not having heat shielding with that much ground clearance and space between the CAT and the bed floor (but it's better to play it safe and get an assembly with shielding as a first preference)
I found this one. https://www.ebay.com.au/itm/Catalyti...W/261225667850
I just pulled the trigger on the headers. not yet decided to buy this.
One of the reasons cat's are mounted so far forward, is that they require high exhaust gas temperature to work properly. 4-600 degrees F before they really do anything. 800 deg F. to be effective. This is why you see manifold cats on so many new cars. Mounting it by the tailshaft or bed will probably render it ineffective and make it prone to clogging. Heat transfer is a product of a coefficient (of the material) and the square of the temperature difference (which would be the pipe to the ambient air next to the pipe). If you graphed your exhaust gas temp vs distance from manifold, you would have an exponential decay graph.
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Originally Posted by geezer101
Thanks Giovanni. Once I get the headers I'll have a better idea what I can do.