Running with no tailpipes

[eric8]

Ok I might get laughed at, but I want to hear opinions. Running an engine with just exhaust manifolds and it "warping the exhaust valves when the ambient air hits them." Any validity to this or is it just an urban legend? I need to drive my new build to the muffler shop which is about 30 mins away. Don't want to risk damaging the new stroker motor so I wanted to hear opinions.

[F-BIRD'88]

I can only see this occuring if also the ignition timing is very retarded and no vacuum advance.. Makes the exhaust valves and seats run very hot over time.
Made still worse if the carb jetting is off..

The result is slow late burning combustion. Really heats up cylinder walls and exhaust valves.

Exhaust manifolds glow..

[SupStk]

I place in in the "old wives" category. Look at WW2 fighter aircraft. Rolls Merlin, Allison, Jumo, Daimler-Benz all had short stacks coming straight out the exhaust ports.

[David Redszus]

I place in in the "old wives" category. Look at WW2 fighter aircraft. Rolls Merlin, Allison, Jumo, Daimler-Benz all had short stacks coming straight out the exhaust ports.

When you run an engine optimization program, the best performance is with exhausts that are zero length.
Not very practical, but it works in theory.

[mag2555]

Ok, which is it!
Your title states no tail pipes on a 30 minute drive and then in your post you say with just exh manifolds.
The problem with just exh manifolds on a 1/2 hour drive is not damaging the valves , it’s catching fire to something under the hood and or melting belts and coolant hoses, and insulation on battery cables unless your just planning on putting along at 20 mph.

I also need to question why with the money you likely have invested in a stroker motor and your running exh manifolds?

[BOOT]

Flex pipe for the win, if you already got good $$$ into it and wanna be sure, what's a few bucks to mock up some kinda dumps just out of the engine bay.

I drove 10 mins with manifolds to a local shop once but they were center dump style in a C3 corvette, I don't think it would be a real issue if your not holding it at rpm and took it easy. We're not talking a 10min burnout to get the manifolds glowing.

[F-BIRD'88]

Flatbed or trailer it there.

[eric8]

Ok, which is it!
Your title states no tail pipes on a 30 minute drive and then in your post you say with just exh manifolds.
The problem with just exh manifolds on a 1/2 hour drive is not damaging the valves , it’s catching fire to something under the hood and or melting belts and coolant hoses, and insulation on battery cables unless your just planning on putting along at 20 mph.

I also need to question why with the money you likely have invested in a stroker motor and your running exh manifolds?

Manifolds had to be used due to no header availability for the application. It's only a 450 hp daily driver build so I really don't think I'll miss the 20 odd hp it should cost me.

The manifolds dump rearward and point down at the ground by the bellhousinh so no worries with catching anything on fire.

[BOOT]

Think Holley just came out with higher flow SBC manifolds

[eric8]

Think Holley just came out with higher flow SBC manifolds

Yep I just saw that after buying some Dorman ones. They even offer coated ones. Not bad looking manifolds!

[6sally6]

IF no chance of a fire .......I would drive it and enjoy-the-wracket!!!!
6sally6