Hey i have a question about my engine smoking. The engine can be kept at a high rev without smoking. Once the blowoff valve opens the car then smoke a bit and stops.

The cars only mod now is forged pistons and rods, stage two cams. Currentlly running stock boost.

Any ideas why it may do this.

 

It smokes out of the bov after you rev it up? Or it smokes just at idle? Forged pistons at idle will most likely not be fully expanded may allow some blowby...

Only reason for this is cuz forged pistons have a completely different expansion and contraction rate compared to the stock cast pistons or whatever they are made of

 

Thanks for the reply.

However, the smoke comes from the exhaust pipe when u come off the gas after it builds boost.

So u go from wot to no throttle, the bov then opens and then you see the smoke for a few seconds. Then its gone, you can then accelerate wot no smoke. It only smokes when you come off the gas.

 

could be turbo,valve seals, or crankcase ventilation issues. have you done a leak down or compression test yet?

 

Thd test would be my next steps.

 

If it's black smoke it is unburned fuel. You are going full throttle to no throttle. If you don't have a cat it will spit a bit black smoke.

 

He has a very good point what color smoke is it?

 

The smoke is sort of blue, it isnt white or black. If i rev and it gets to redline it puffs a bit of black smoke which i think is normal.