Need advice my Cobra is smoking

[xTomKx]

Some time ago my 96 cobra started smoking. Over time it got worse. Last time I drove it it smoked very bad once it got to operating temperature.

I checked compression and got following numbers

200 201
195 194
195 81 (95 with oil)
191 192

I also used my neighbor's borescope to look down the cylinder but could not see any damage.

The shop manual says that if the rings are bad I should see a significant increase with oil. 14psi does not sound very significant to me.

Does this indicate a bent valve or bad rings? Would like to get some advice on what could be the issue before I pull the motor.

 

[encasedmetal]

the valves on that cylinder are the culprit.

 

[mysteed]

I'd be leaning toward an issue with the valves. How many miles are on the motor?

 

[goats]

A leak down test will tell you what's up

 

[xTomKx]

I'd be leaning toward an issue with the valves. How many miles are on the motor?

76k on the motor. But I'm running 13psi of boost on a stock block.

 

[na svt]

The engine has to come out and the head has to be removed regardless of the cause.

 

[xTomKx]

The engine has to come out and the head has to be removed regardless of the cause.

I have to pull the engine to remove the heads?

 

[na svt]

I have to pull the engine to remove the heads?

No, but you'll want too. R&R'ing heads in the car is huge PITA.

 

[bergz22]

Yes they are, I was in the process of doing a cam swap into mine, had a bad cam journal with 46k miles, just pulled the whole engine. You can pull the heads in the car, but it is not easy at all.

 

[Boss 327]

What color smoke?

 

[Wynn]

I need to do a comp test on mine again. I had 160psi with a 120psi cylinder. Im interested to recheck it and see if the fuel/nitrous mix cleaned that valve and increased the psi in that cylinder.


Good luck with fixing yours. Post up what ya find