calongo_SS

iTrader: (7)

What caused the pre igntion? It surely wasn't too much timing, because igntion before the spark is not directly caused by the event which hasn't even happened yet. What is it that set off the charge before the spark?
How can pre ignition cause detonation?

Maybe we are just going by a different definition of detonation. I am saying detonation is any secondary ingnition after spark. From the quote above it seems to be eluding to detonation being a situation where there are flame fronts coliding.

The main problem I am having with understanding you explanation is you are saying the motor survived pre-ignition and was then killed by detonation. Pre ignition will kill the best built motor imaginable in seconds, detonation will not necessarily cause immediate engine damage.
Another problem I have with the quote above is saying pre-igntion occuring 30 deg BTDC (in the case of your motor 5 or so deg before spark), that is far from the most likely place to have pre ignition. As the piston rises, the pressure goes up and it becomes more difficult to ignite. 180 deg BTDC is the most likely place to have pre-igntion because the pressure is the lowest.
What happens when a motor goes into pre-igntition? It generally burns a hole through the piston, it doesn't cause detonation.

WizeAss

iTrader: (5)

thanks dave......

WizeAss

iTrader: (5)

so....by looking at my plugs.... do you think the lack of proper gas(109 vs the original 116), hot plugs, faulty fuel selenoid, or too much timing was the problem? could it have been detonation or pre-ignition

Pro Stock John

iTrader: (34)

Does vid #3 sound like metal on metal?

If the car sounds messed up, I'd assume that you at least have a bad valve, so it's time to fix it.

TINKRD

iTrader: (27)

has TRT not done a leak down on it yet?

GS WS6

Ttt...

383LQ4SS

iTrader: (33)

at your HP level you should have slid each of those parameters to be firmly in the safe zones. It appears you had 2 out of 3 just beyond safe...but was making up for it with the octane in the past. When you slid the last parameter (octane) down a bit....you were done for.

Definately too hot of a plug
however had you had 116 fuel you may have gotten away with it.

Definately too much timing...but again...with 116 you may have gotten away with it

So why not go with 1) colder plug 2) less timing and 3) stick with 116.

Youll be SQUARELY in the safe zone...probably with room to spare.

as for the fuel noid...you need to inspect that and test it to ensure its operating right.

TX_SS

iTrader: (4)

who broke your car this time?? YOU~??? thought your daddy told you not to play with a fire... hope you didnt miss the 3rd... LOL

WizeAss

iTrader: (5)

nope....only hutto has managed to blow it up missing a gear before.

Robert56

iTrader: (2)

Preignition can happen at any time after the intake valve opens to start letting in the a/f/n2o mix. Many things can cause this preignition, but in context to spraying we are talking; a couple of revolutions with too much timing and spraying leads to very high cylinder pressures and heat, bingo, there is our source for pre ignition the abnormally high temps. Depending on when this happens, it can leave unburnt mix for after running or detonation to occur, pretty simple really when we consider what nitrous and timing do to the timing events; and the reason we need to retard the timing. Facts are nitrous needs reduced timing to work with the best VE and do it safely. I know it's a little confusing, but preignition and detonation are two seperate things, but pre ignition can lead to detonation. The problem with preignition is you won't allways detect it happening, but with gobs of timing on the spray we set the stage for sure, for one or both. I think we both have a good grasp, as both can happen for a number of reasons and there is no absolutes, and thus the disscussion.
Robert

calongo_SS

iTrader: (7)

OK, I kind of see what you are saying now, but I think in the scenario presented the preigintion would still be the killer. But like you said there are no absolutes in trying to figure out exactly what happens when things go wrong in a motor.

Micheal@TRT

First off, I didn't tune the car, so I had no Idea the timing was at 26, as a rule of thumb you retard 1 to 1 1/2 degress for every 50hp of nitrous. Mikes car made max power with between 30-32 dgs if I remember correctly, so the timing was retarded and no problems were detected on the dyno or the track. I personally pulled the plugs after Mike had used 2 bottles and they looked great. As far as the TR6's being in his car, yes that was my bad because we couldn't find them in time for him to race jeremy, I then forgot about them being in there, after all Mike is not our only customer and I can not keep up with what everyone has. I do know they were gapped at .028 and his car was setup for 116 octane. The whole problem is lack of getting the right equipment, lack of pateince, and misunderstandings. I am planning on going to Mikes house and doing a leak down on it one day this week to save him on towing it to the shop.

slowredz

iTrader: (23)

The car runs on 116 in the tank and stand alone? Or pump in the tank and 116 in the stand alone? "Forgetting" stuff when you are running that much nitrous will usually end up blowing something up.

big thumper122

iTrader: (1)

TRT did nothing wrong imo...and I'm definatly not a swinger for them...just saying. The customer cut corners, the customer wanted it done quicker than necessary, and the customer tried to hot lap it on a big shot...the shop can do the labor, put it together, tune it, and send it out the door. They can not however make the person driving the car use some semblance of common sense.

Sam88Gta1

iTrader: (13)

I run 25* of timing on a 225shot with pump gas and #7 plugs.

Then again I dont care if I hurt my motor.Could be the reason its lasted 60something bottles like this.

I run 30* of timing on motor and last week loaded the wrong tune in sprayed the truck and burned 7 plugs at one time. Changed the plugs and she was back to normal.

Oh yeah...Mike you need to step back and stop rushing.

WizeAss

iTrader: (5)

I agree..... that is the plan. This lesson will make me much more careful.

I need to stop expecting the red "easy" button for everything.

WizeAss

iTrader: (5)

116/93 at 26 degrees... thru 2 bottles in the heat looked fine with the TR6's gapped at .28

Next time I am going to start with 111/93 at 22 degrees with TR8's at .32 and check the plugs each pass.

WizeAss

iTrader: (5)

Do you change all 8 plugs... or can you just do number 1/2/4/7?

Number 8 and 3 are a bitch to get to!

SMKN TA 95

iTrader: (46)

Here is a run down of what I am using with a similar plate. I use the NX Gemini Twin plate that sprays around the perimeter, modfied/new line from the solenoids to the plate for equal dist.

Engine: 14.5 compression 404ci, iron block

Fuel: VP Nitrous fuel, 120 octane

Plugs: NGK 11's

Nitrous: Spraying 200hp

Timing: Pulled 12 degree's timing (16-17 degrees total)


You should take your time when you use nitrous on any engine. A friend of mine tunes PRO nitrous cars, and we took our time on mine. We were surprised it took 12 degree's of timing pulled to get the plugs to read right. We also run the car at about 10.6-10.8 AFR. The plugs look great, and we havent even leaned on it yet. But I wanted to be safe when I started spraying a engine that I invested TON of money in.

My best advice for when you spray again.... run the C16 and NGK 9's or 10's. Better to be safe than sorry.....its not hard to swap the plugs to a warmer one

WizeAss

iTrader: (5)

I assume that is a solid roller? I will take your advice..... swap back to 116 or better gas, use some TR8's, use only 1 kit with a bottle heater and gauges pilled for a 200, and put the timing at 20 degrees. I am running only 11.25:1 compression, so I assume that helps a bit.

Like I said... was fine on the first 10 runs with 116 in it. I am sure dropping it to a 200 and pulling 6 degrees with colder plugs should be safe enough based off our previous findings.... also the IAT's are going to drop with this 60 degree weather now.