I hurt it on a 175 shot, got some questions.
10-27-2008, 09:54 AM
#1
I hurt it on a 175 shot, got some questions. I see guys on here spraying 250 and 300 on PUMPGAS! I obviously got lazy and took some peoples word for it being "safe".
Here is the setup
383 LT1
12.6 to 1 static compression on 93 Shell pumpfuel
Holley bigshot 4150 plate system jetted per NOS recs 73n/82f flowed at 6 psi
Autolite 3923 plugs
Accel 300 and 375 boxes with 7 degrees pulled out
Stand alone cell with Holley black pump and 116 fuel
Has a functioning PCV system but goes through a seperator mounted lower than the engine so its harder for the oil to travel uphill to make it into the elbow.
Blew hole in #5, was fixin to do it in #8. Did this on a 1/2 a bottle used.Also used almost a 1/2 gallon of fuel along with the 1/2 of the bottle.
I think it was too rich. All the other pistons look perfect, no ring lands pinched.
SOmeone give me a good baseline tune for when I get it back together.
Any input appreciated, thinking seriously about taking it off the car, loosening up the converter and leaving it alone. will run 10.80's with a looser converter on the motor. And I can drive it anywhere. I am able to put the a/c back on it as I have solved the running warm problem.
WHat you guys think?
Here is the setup
383 LT1
12.6 to 1 static compression on 93 Shell pumpfuel
Holley bigshot 4150 plate system jetted per NOS recs 73n/82f flowed at 6 psi
Autolite 3923 plugs
Accel 300 and 375 boxes with 7 degrees pulled out
Stand alone cell with Holley black pump and 116 fuel
Has a functioning PCV system but goes through a seperator mounted lower than the engine so its harder for the oil to travel uphill to make it into the elbow.
Blew hole in #5, was fixin to do it in #8. Did this on a 1/2 a bottle used.Also used almost a 1/2 gallon of fuel along with the 1/2 of the bottle.
I think it was too rich. All the other pistons look perfect, no ring lands pinched.
SOmeone give me a good baseline tune for when I get it back together.
Any input appreciated, thinking seriously about taking it off the car, loosening up the converter and leaving it alone. will run 10.80's with a looser converter on the motor. And I can drive it anywhere. I am able to put the a/c back on it as I have solved the running warm problem.
WHat you guys think?
10-27-2008, 10:24 AM
#2
Guest
Posts: n/a
What was your existing tune?
NA Timing?
A/F ratio?
And did you have any issues with oil in the intake?
I currently have mine jetted for a 200 shot.
93 octane in the main tank, C16 in the dedicated.
36* NA timing, pulling 9.9* on the bottle.
AR3933 or NGK R5671A-9 plugs (AFR Heads)
high 11 A/F ratio
I noticed you said you used half a gallon of fuel with only half a bottle of nitrous? I have run multiple bottles of nitrous on a single tank of fuel. I also still have around 1/2 a tank left.
I am also showing the AR3923 cross references to a heat range 5-6 plug
Autolite Racing__ AC Delco__ Champion __ NGK ____NGK Stock Number
AR3923___________________RC9YC _____BKR6E __6962
Called NOS and verified base jetting for the bigshot plate. The 175 is the min. recommended jetting for that plate.
Fuel jetting was 6psi. But they still suggest verifying A/F ratio to dial in the correct tune.
Last edited by Ray@Nitrous Outlet; 10-27-2008 at 10:54 AM.
10-27-2008, 11:38 AM
#4
Plug pics wont do any good, soaked with oil from the popped piston.
Go here for pics
http://www.yellowbullet.com/forum/sh...ad.php?t=84701
Go here for pics
http://www.yellowbullet.com/forum/sh...ad.php?t=84701
10-27-2008, 11:42 AM
#5
The holes were caused by detonation. We need to find what caused the detonation.
What was your existing tune?
NA Timing?
A/F ratio?
And did you have any issues with oil in the intake?
I currently have mine jetted for a 200 shot.
93 octane in the main tank, C16 in the dedicated.
36* NA timing, pulling 9.9* on the bottle.
AR3933 or NGK R5671A-9 plugs (AFR Heads)
high 11 A/F ratio
I noticed you said you used half a gallon of fuel with only half a bottle of nitrous? I have run multiple bottles of nitrous on a single tank of fuel. I also still have around 1/2 a tank left.
I am also showing the AR3923 cross references to a heat range 5-6 plug
Autolite Racing__ AC Delco__ Champion __ NGK ____NGK Stock Number
AR3923___________________RC9YC _____BKR6E __6962
Called NOS and verified base jetting for the bigshot plate. The 175 is the min. recommended jetting for that plate.
Fuel jetting was 6psi. But they still suggest verifying A/F ratio to dial in the correct tune.
What was your existing tune?
NA Timing?
A/F ratio?
And did you have any issues with oil in the intake?
I currently have mine jetted for a 200 shot.
93 octane in the main tank, C16 in the dedicated.
36* NA timing, pulling 9.9* on the bottle.
AR3933 or NGK R5671A-9 plugs (AFR Heads)
high 11 A/F ratio
I noticed you said you used half a gallon of fuel with only half a bottle of nitrous? I have run multiple bottles of nitrous on a single tank of fuel. I also still have around 1/2 a tank left.
I am also showing the AR3923 cross references to a heat range 5-6 plug
Autolite Racing__ AC Delco__ Champion __ NGK ____NGK Stock Number
AR3923___________________RC9YC _____BKR6E __6962
Called NOS and verified base jetting for the bigshot plate. The 175 is the min. recommended jetting for that plate.
Fuel jetting was 6psi. But they still suggest verifying A/F ratio to dial in the correct tune.
Total timing on motor was 32 or 34, cant remember
A/F ratio on dyno was 13.0 on motor on the dyno.
No oil issues in intake, only a small film and tint just like all pcv systems do.
I was told it popped the ring land becaust it was too rich, oil enetered the hole and it was all over, BUT does not explain#8, the ring land was fine but the piston top was distorted.
#5 and 8 both had the strap on the plug burned off. Kinda weird cuz this engine was hurt the first time on the dyno and it popped the ring land off #8 on the motor, I found out why much later. The IAT sensor wire had an open circuit, did not set a code. I stumbled onto it one day with a scan tool.Read -40 degrees, has since been fixed but not retuned. Runs fine.
10-27-2008, 12:13 PM
#6
Guest
Posts: n/a
7* from that should have been fine
What was it on the bottle?
My guess is detonation caused by either wrong spark plug or A/F ratio related. From the pistons I would say lean as the heat is in the center. I read the post on Yellowbullet and the PCV might have been an issue but not the whole cause. I agree that it was a factor of multiple issues that ganged up on you.
What was it on the bottle?
My guess is detonation caused by either wrong spark plug or A/F ratio related. From the pistons I would say lean as the heat is in the center. I read the post on Yellowbullet and the PCV might have been an issue but not the whole cause. I agree that it was a factor of multiple issues that ganged up on you.
10-27-2008, 12:45 PM
#7
Ray, do I need a non projected tip plug such as a 3933, or one colder?
If it was lean, why so much fuel used out of the cell? Using 1/2 a bottle on a 175 shot should use no more than a quart I would think.
13.0 A/F was on motor only, gas was not even on the car when it was tuned on the dyno.
SO If I am gonna streetdrive this car which is what I do with it, I cant spray as long as the pcv is hooked up? Under WOT PCV should be not working at all. Only under high vacuum situations such as idle and cruise.
If it was lean, why so much fuel used out of the cell? Using 1/2 a bottle on a 175 shot should use no more than a quart I would think.
13.0 A/F was on motor only, gas was not even on the car when it was tuned on the dyno.
SO If I am gonna streetdrive this car which is what I do with it, I cant spray as long as the pcv is hooked up? Under WOT PCV should be not working at all. Only under high vacuum situations such as idle and cruise.
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10-27-2008, 12:53 PM
#8
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Can't say with 100% certainty either way on this. Any oil or coolant in the cylinders can cause detonation. You just need to ensure that it doesn't happen. I don't run a PCV on mine, only breathers on the valve covers
10-27-2008, 01:08 PM
#9
Ray@Nitrous Outlet;10369578]not sure if the 3933 is the right plug for your head, but I would go colder on the plug
SUpposedly its the same as the 3923 but nin projected tip.
The amount of fuel used out of the cell, was a concern of mine also, but without knowing A/F ratio we are just guessing as to if you were rich or lean.
Did you "tune" the nitrous on the car?
The best I knew how, which shows I dont know enough. Not on the dyno though.
Can't say with 100% certainty either way on this. Any oil or coolant in the cylinders can cause detonation. You just need to ensure that it doesn't happen. I don't run a PCV on mine, only breathers on the valve covers[/QUOTE]
Do you street drive yours? If I take it off I will most likely have a moisture in the oil.
SUpposedly its the same as the 3923 but nin projected tip.
The amount of fuel used out of the cell, was a concern of mine also, but without knowing A/F ratio we are just guessing as to if you were rich or lean.
Did you "tune" the nitrous on the car?
The best I knew how, which shows I dont know enough. Not on the dyno though.
Can't say with 100% certainty either way on this. Any oil or coolant in the cylinders can cause detonation. You just need to ensure that it doesn't happen. I don't run a PCV on mine, only breathers on the valve covers[/QUOTE]
Do you street drive yours? If I take it off I will most likely have a moisture in the oil.
10-27-2008, 01:17 PM
#10
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