I will start off by putting the link to my build thread for those to see some background of the car.

https://www.evolutionm.net/forums/ev...0hp-360tq.html

So onto the things I am needing help with from you experts and seasoned vets. Car started to smoke back in Octbober before I parked it in the garage after I would do a WOT pull. Car never smokes under idle or normal driving conditions. We pulled compression on all four and number 4 was reading low as 96 the rest showed right at 125 to 138.

So my first guess is the ringland is cracked on number 4 but could there be another issue going on. The reason I ask this is because the car runs the exact same only reason I knew there was something going on was the change in idle and the smoke after a pull.

I want some help with the direction I should go so I have a reliable DD with a turbo upgrade and engine build but first would like to talk about the other issues first.

 

Any oil on #4 spark plug? The next step would be a leak down test and to drop a scope in the cylinders to see if there is anything ugly. How is your oil consumption?

 

No oil on the plug when we pulled it and oil consumption is very little to none. Leak down is what I will pursue next.

 

Agree with packrat.. cylinder leak down to see. leaks out of exhaust or intake then have a valve issue. out of the crankcase would have ring issue.. dont see that there would be a drastic failure being you dont have terribly low compression. also you could do a wet compression test..(put small amount of oil in the cylinder).. if compression would raise then ring issue.