Black puff of exhaust.

[robert leazenby]

This last weekend I took my 70 LT-1 to Las Vegas. Initially I had a problem with detonation due to the change of altitude. I located some 100 octane gasoline which curred that problem. (The car does not pre-detonate at home, 6500' elevation)

The car ran great, very strong. However; The guy traveling with me noticed that when I accelerated hard there would initially be a puff of black exhaust. Would that be a fuel/air mixture problem. The car is equipped with the stock type Holley.

Also for some reason after a couple of days, pressure in the motor forced out the rubber gasker between the intake and the front of the block. Possibly from high rpms?

[Wayne W.]

Re: Black puff of exhaust.

A little black puff is common for hard acceleration.

[Wayne W.]

Re: Black puff of exhaust.

A little black puff is common for hard acceleration.

[Duke W.]

Re: Black puff of exhaust.

Normal driving causes some deposits to build up in the exhaust system, and the initial exhaust pressure waves when you go to WOT can break them loose and cause a brief puff. Like Waynes says, it's normal.

Regarding the gasket dislodging, check that your PCV system is properly configured including a correct and properly functioning PCV valve.

Duke

[Duke W.]

Re: Black puff of exhaust.

Normal driving causes some deposits to build up in the exhaust system, and the initial exhaust pressure waves when you go to WOT can break them loose and cause a brief puff. Like Waynes says, it's normal.

Regarding the gasket dislodging, check that your PCV system is properly configured including a correct and properly functioning PCV valve.

Duke