sloLs1
05-28-2010, 08:51 PM
ok soo a few weeks ago i was playing around in my saturn(4 cyl + supercharged) and when i was making a pull attemping to tune it and i definatly lost a cylinder and blew the dipstick out..... ok so i figured i melted another piston. Ive done that a few times due to the shitty hyper pistons and no timing control......
anyway long story short, the car had a slight miss fire at idle( not a dead hole) when you would drive the miss would go away and everything was fine(obviously a little bit of pressure not quite boost was making up for compression lost?!) sooo i pulled the plugs cylider 2 and 4 were slightly wet but no signs of detenation or anything(they looked good) sooo i cleaned up drove it again same shit i figured i melted the top ring land of a piston.
so today i pull the head off to find absouletly perfect looking pistons and cylinder walls. the only thing i could see which the question im getting at is how close of a tolerance should be between the piston and the cylinder wall??? it looked like the pistons were too small for the bore?! ive built more than a dozen of these motors and always send the pistons with the block to get bored to fit.... oooo AND FORGOT to mention this motor has roughly 4k N/A miles and 400 boosted miles....
ok so recap... main question is what is the tolerence for pistons to cylider walls... how do you measure?? and do you think i could have possibly burned a piston ring?!? thats the only thing i can think of... i havnt pulled the oil pan off yet to get the pistons out..........
anyway long story short, the car had a slight miss fire at idle( not a dead hole) when you would drive the miss would go away and everything was fine(obviously a little bit of pressure not quite boost was making up for compression lost?!) sooo i pulled the plugs cylider 2 and 4 were slightly wet but no signs of detenation or anything(they looked good) sooo i cleaned up drove it again same shit i figured i melted the top ring land of a piston.
so today i pull the head off to find absouletly perfect looking pistons and cylinder walls. the only thing i could see which the question im getting at is how close of a tolerance should be between the piston and the cylinder wall??? it looked like the pistons were too small for the bore?! ive built more than a dozen of these motors and always send the pistons with the block to get bored to fit.... oooo AND FORGOT to mention this motor has roughly 4k N/A miles and 400 boosted miles....
ok so recap... main question is what is the tolerence for pistons to cylider walls... how do you measure?? and do you think i could have possibly burned a piston ring?!? thats the only thing i can think of... i havnt pulled the oil pan off yet to get the pistons out..........