Review on Dorman 674 512 Exhaust Manifold Kit by Shaylon Bateson

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 significantly smaller than the stock manifold, more than 1/4 inch smaller. I have a feeling that a smaller port diameter will inevitably result in some performance loss. It appears to be just a sloppy cast with irregularly shaped openings. The heat shield that came with the manifold didn't have a hole for the oil dipstick, a few more minutes with the dremel and it was done. a car with only 100 hp, I don't want to lose power. I was able to get a good aftermarket header for twice the price and considered sending it back. The need to have the car on the road has kept me from returning it and having to keep using it. I'll probably buy a new head later to replace this one later. Ports are properly aligned Overall, it's not a bad product, but it's not a great product. your repair priorities. You get what you pay for.