NoGamesLS1

iTrader: (16)

Motor has about 25k miles on it. Its a 393, 4.1 stroke x 3.9 bore. Car is very strong and makes great power, but under wot it blows smoke. Its done this for a while, possible since the motor was first built, but I just can't remember for sure. The rings are gapped for 250 HP nitrous shot (don't recall actual gap numbers). With that being told, is the smoke just the nature of the beast when the rings are gapped wide? Thanks

PS I have a catch can and there is no oil in the intake. Heads have maybe 10k miles on them. Car seems to burn about a half a quart per thousand miles.

LS6427

iTrader: (2)

Is it pure white smoke?

When you go WOT and it starts to smoke.....does it keep on smoking the entire time you are on the throttle.......or does it slowly clear up as you stay on the throttle?

If it keeps coming out....rings.

If it slowly clears up.....valve seals.

.

NoGamesLS1

iTrader: (16)

The smoke is dark. I will have to see if it keeps smoking at prolonged rpm, but I think it clears up. If it is the valve seals is there anything that should be done, or just keep running it?

LS6427

iTrader: (2)

Dark smoke usually means your running rich at WOT..........

White/bluish smoke is oil...........

Bad valve seals just burns oil. You need to remove the heads to fix them.

Try cleaning your MAF....it comes into play when you go WOT. Maybe its just dirty.

.

NoGamesLS1

iTrader: (16)

Running speed density and e85 at 30% rich in mid rpm tapering to 20% rich in high rpm.