Dorman 674 512 Exhaust Manifold Kit Review

Unfortunately this exhaust manifold cracked right between 2 and 3 issues. Unfortunately, they don't make replacement parts that last.

This arrived with the wrong seals, some of the hardware was also missing. When I installed the O2 sensor in the manifold all threads were stripped completely and I just tightened it with an 8" wrench. useless now, what a waste of time

Can't beat the price, one O-ring was missing but all the bolts, nuts etc were OEM. broke 3 bottom nuts/bolts on a 1998 former 14mm deep civilian coupe, 2 extensions, cheater pipe breaker, and it pops and unscrews perfectly. Thank you Honda and Amazon.

Worked great on my 1995 Honda Civic Si. It's thicker and heavier than my standard, which is a good thing. They know what to hack into this engine. At the same time I changed the O2 sensor. The engine would strangely pick up speed slightly, then drop back down, then pick up speed again on the idol. If you change this, this problem has also been fixed. It fits perfectly and my car works great. Checked it today and it was torn in four places. It should take longer than before.

Hello, I've just fitted a Dormans header and there are a few little things to know, firstly Honda made some cars in the US and some cars in Japan, in US cars use 2 9/32" gaskets, the ones that come with the kit are for Japanese models and reuse the factory metal gasket on the cylinder head whenever possible and I also put in a bit of time and cleaned the connections with a dremel. Once you fixed these little issues everything else is great and working great hope this helps the next guy i buy…

It may have worked for others, but it turned out to be complete garbage for me. The casting is very rough and all the outlet ports have burrs on the edges. I suppose I could sand them down myself, but shouldn't such things be the responsibility of the manufacturer, not the buyer? Very low quality. To top it off there are 3 threaded holes on the back of the manifold which are not used on my particular Honda Del Sol model and one of these holes was overdrilled and actually drilled through the…

The product works fine but there are a few oddities. If you are looking for the cheapest replacement that works then this is it. But it doesn't meet OEM specifications. The openings where the manifold meets the head were oval curved and significantly smaller than the outlets on the head. This can create significant back pressure directly at the exhaust valve. A few minutes with a grinder opened up the port to eliminate any back pressure due to the raised edges. On the manifold side, the hole is