Is this really bad to do?

[Motorhead350]

I heard mixed answers so I want yours. Is it bad for an engine to drive with open headers. Some I heard it isn't, some told me it melts the heads because of lack of back pressure. Is this bad, just bad for fuel injected cars... exc :confused: Thanks

[Ozz]

No, IMO it's fine. As long as you have sufficient header length to prevent cold outside air from hitting the valve stem there should be no problem.

If you run NO HEADER, the cold outside air will hit the valve and cause it to warp. Same thing can happen if you have an extremely bad manifold/header leak to the head.

[gamercfan]

Ditto with ozz. However, open headers could actually be a negative for performance. A certain amount of backpressure is required for how your engine is set up (most important the type of cam). It can drastically affect the troque curve, and ratio of rpm to torque at various engine speeds. You can setup the engine to run best with open headers but that is usually a pure drag racing or racecar configuration.

[Blackened300a]

I have always been told that open headers will result in burnt valves.
Like was said before you need some back pressure for the engine to run correct.

[SergntMac]

Open headers will improve high RPM breathing, which will produce more power in the high RPMs, but at the cost of low end torque.

Our 281 CID engines need all the low end torque they can get, so, IMHO, it's not a fair (or wise) trade off.

[Motorhead350]

Yea the Marauder goes slower, but when my truck had a carb it would shave .3 seconds off the 1/4 mile.