Hello all, I finished my LS/vtec build about 6 weeks ago and I am having a major problem with oil blowing out of the exhaust. It goes through about a quart a week like this. There is no leak on the engine, I have checked over and over. When I rev hard you can see a black spray out of my exhaust on the ground. When we installed the pistons, one of the lower rings bent a little, but we was told by a mechanic that it would be ok to flatten it back out and use it. Do you think this could be the issue? I have B18b block w/b16 head. b16 pistons and LS rods. If anyone has any insight before I tear it back down, please chime in. Thanks guys,
Drew

 

With the ring messed up and fixed it won't be exact, that is causing what is known as blow by, all engines do it(slightly), but yours is doing it more because of that one ring. When rings are installed they have an almost perfect seal end to end, when one of them is bent out of spec and bent back by hammering or clamping what have you. This will cause the two ends of the ring have a small gap.

 

that is what I was thinking, someone also suggested it might be something to do with the valve seals or guides. I took the head str8 off of the b16 and put it on b18. It could not have messed up that quick could it??

 

take your header off and see what cylinder or cylinders shows signs of oil. If its the cylinder with the bent ring then thats probably your problem. Otherwise its still a good starting point to find out where your problem is coming from

 

rock on, I am going to pull the plugs tomorrow and see if the oil buildup is in that cyl. Thanks guys,