I've been going to town on the 455 doing all I can. It runs much better with new plugs and a basic tune up. Took it for its first decent ride today since I drove it home. It runs great and doesn't act weird at all but it gets a weird smell when it runs for awhile. I can't seem to figure out what it is. No smoke from the muffler and the coolant temp stays at 205F but everytime I run it for a little while the smell is noticeable. I can smell it in the cab and outside the car. I've heard old exhaust systems will create a weird smell. Could that be what it is after the cat gets good and hot?

 

It could be the cat. They never stayed in any cars long enough for me to know what they'd smell like when they got old.
Hot metal has a smell, if your exhaust is restrictive in a certain spot it will get hotter there and make a smell.
If the valve seals are cracked a small amount of oil could go into the exhaust valve. Might not really enough to smoke, but enough to smell.
You could have some oil leaking onto the exhaust manifold.
It could be running rich or have a slightly leaky fuel line or something.
Is your transmission acting up?

 

Nope tranny seems to be doing just fine. No has smell in oil and it was fine after changing it no smell or lighter color. The value seals are leaking a little noticed it on the outside of the plugs when I changed them. Could that be it?

 

Possibly. My seals leak slightly too, doesn't smoke or use any noticeable amount of oil, but has a smell.

 

Well that would be a easy fix $20 seals and a torque wrench. Thanks for the input

 

I laughed my a** off on the cat reply . Way to go Jedidiah

 

@ 205 degrees are you smelling burnt coolant ?

 

Any new paint on the engine- especially around the exhaust crossover area?

 

That was my first thought but wouldn't there be some kind of discoloration in the oil? Even the old oil that was in it for god knows how long

 

Also the way you worded that is 205 high? As much as I could find online it seems pretty normal. Maybe 5 over but nothing crazy high. I haven't flushed the coolant yet because it looks brand new

 

It's a little high bot not by much. I mean venting from the cap is where you may be smelling something. If the cap won't hold pressure it will vent steam for the most part. You don't have to worry about blown head gasket. Yet....

 

Should probably flush the coolant and see what it's running at? Def don't feel like replacing a head gasket already. Got another problem now. It got down to like -10 and now it won't start....... It will spudder if I spray carb cleaner in the carb but gonna replace the fuel filters and go from there

 

At that temp the lines may be freezing up. I'd wait for some warmer weather if you can hold out.

 

Not sure of the specs on your engine but I once had a Mopar with a 10:5/1 comp ratio and was in poor tune (carb issue) . Ran reg unleaded in it one time by mistake and the exhaust would make your eyes water. The smell was very strange. Not like unburnt gas at all........

 

I didn't realize this may of sat for a while. I'm thinking it may be the mufflers burning off whatever junk was in them. You should still be running a little cooler though.