Intake Backfires
Thread Starter
On The Tree
Joined: Jan 2004
Posts: 188
Likes: 0
From: Houston/ Austin, TX
Intake Backfires So im having a debate with a local friend about nitrous oxide and he is trying to tell me that with too much spark advance (even on a stock LT1), the charge can detonate and cause the flame to travel BACK up the intake as an intake backfire.
I really dont wanna say he is wrong, because I have ALOT of respect for the guy and hell... he has a nitrous fed 396 LT1 running in the 9's, so I would assume he knows a thing or 2 about nitrous.
I just dont understand how a motor can backfire up the intake valve once it is already closed. On a stock cam, the intake closes at ~30* past BDC and the spark is advanced roughly 30-40* before TDC, which gives the crank NO LESS than 110* between the time the intake closes and the spark comes. Even if the intake does bounce, it doesnt bounce for 110* of crank rotation.
How could that be possible? Am I missing something?
I really dont wanna say he is wrong, because I have ALOT of respect for the guy and hell... he has a nitrous fed 396 LT1 running in the 9's, so I would assume he knows a thing or 2 about nitrous.
I just dont understand how a motor can backfire up the intake valve once it is already closed. On a stock cam, the intake closes at ~30* past BDC and the spark is advanced roughly 30-40* before TDC, which gives the crank NO LESS than 110* between the time the intake closes and the spark comes. Even if the intake does bounce, it doesnt bounce for 110* of crank rotation.
How could that be possible? Am I missing something?
