DodgeIntrepid.Net Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
371 Posts
Discussion Starter #1
Could someone please explain detonation to me, i know its bad and is a problem especially in turbo cars but i dont really understand what it is. Thanks
 

·
Registered
Joined
·
371 Posts
Discussion Starter #3
thanks that helps alot
 
  • Like
Reactions: Minagera

·
Registered
Joined
·
328 Posts
Detonation is the fuel in the combustion chamber does not burn but explodes instead. This is bad becused it creates a shock wave going the opposite direction of the normal burn. When the two meet, there is impact, this impact is what you hear in the pinging.
Fuel should burn smoothly starting at the spark plug and speading out evenly.
If you use a fuel with too low octane, on compression, the fuel starts to burn then the pressures execed the fuels resistance to exploding and it explodes instead of burning.
As octane increases, the reistance to exploding increases (good for high compression engines)

Preignition is different, its caused by hot spots (carbon, wrong heat range plugs) and its when fuel is ignited at the wrong time by these hot spots. Poor quality fuel and additives can cause these hot spots.

Both are distructive to engines, causing cylinder overheats and thus causing hot spots and even greater cylinder over temps.

The knock sensor detects DETONATION, not preignition. It tells the computer to retard the timming untill knocking is gone (thus less power)

Youy should use an octane of fuel that does not knock, but going to a greater octane than that is a waste of money.

the 3.5L engine has a very high compression ratio ~10:1 so using anything less than 89 octane will cause detionation and timing retard.


Hope this helps, using good gas, right plugs and keeping the ignition system in good working order are the best things to combat Detonation and preignition
 
  • Like
Reactions: spatulahunter

·
Registered
Joined
·
415 Posts
Hey mate, I think he was talking about the Talon TSI
 

·
Registered
Joined
·
328 Posts
Don't mater what car it is, Detonation is Detonation, preignition is preignition.
 

·
Registered
Joined
·
371 Posts
Discussion Starter #7
Minagera said:
Hey mate, I think he was talking about the Talon TSI
correct. I havent started raising the boost yet because i still have alot to learn about a turbo system and i dont want to blow up my motor. I read the dsm forums alot and they all talk about detonation and other things but alot of them are really assholes when compared to the people on di.net so i figured i would just ask on here.
 

·
Registered
Joined
·
728 Posts
How much boost you running and whats done to it? My cousin and I put a full 3" exhaust on his car and run 18/19psi on an otherwise stock 96 talon with no probs. oh yes and a 1g bov...crappy 2g one leaked at 15psi. Hope you have a a/f gauge atleast and should get an egt gauge.
 

·
Registered
Joined
·
371 Posts
Discussion Starter #9
i have the guages, an intake, and a bov but i havent put anything on the car yet. As of right now its completely stock.
Does he have an upgraded turbo because as far as i know the t25 that comes stock on a 2g dsm is running at max boost stock.
 
1 - 9 of 9 Posts
Top