Spark plugs oily on #4 & #8 cly since head swap

[50canuck]

Could i have a valve seal problem? I looked at old heads , plugs in same clyinder locations are clean. Engine idles a little rougher, and didn't seem to make as much power as predicted. 86gt bottem end, e7's. cobra I/T, 1 5/8 headers, pullies > made 219rwhp/278rwtrq. .Old combo> with e6's . 201rwhp/280rwtrq

 

[vristang]

I would look at the valve seals first. Not sure what else could make the back two cyl'S oil up. Weak ignition maybe?


Stock heads are pretty lame though. Run away! Run away!