sound of detonation....?

copex · 8-2-07, 0:05

okay... ummm can anyone describe or have a sound clip of what detonation sound like on our mx-6?
Coz I get a poping sound once or twice a week when going up a hill boosting @ 5-7psi(wastegate spring 5.63psi or something I cant remember). Only 1 pop every time... a crispy pop a bit like throwing a small rock at a brick, might that be my external wastegate opening? (no screamer pipe or rec back to exhaust)

this happens too even in really cold rainy weather at night on the same slope, probably the only place I get to full boost and make use of my wastegate.

I've never had more than 1 pop each time and the car gets a sudden push in the back after the pop with the the same boost pressure.

Would that be the VRIS kicking in? the pop happens above 4,000rpm

not much of a problem to me at all but what could the sound be?

**KING6** · 8-2-07, 0:26

It would sound like a metalic ping.

-sitting back and watching this car blow up just like predicted

copex · 8-2-07, 0:46

well not very metalic to me atm :/ abit like throwing a frozen can of coke on the ground.

sorry but I'm adding water injection to my setup in a few months ^^ maybe you should start praying for my water tank to run dry now?

**KING6** · 8-2-07, 1:00

if it makes it that far

**turbociv920** · 8-2-07, 2:23

your car might hesitate or act funny when it does.....

put 110 octane in there and see if it still pops.. if it does its not knock.. i mean detonation..stuck in a dsms world O_0

copex · 8-2-07, 2:40

hmmm using 98 right now I cant get race fuel so do I just add methylated spirit to my fuel tank? LOL

**turbociv920** · 8-2-07, 2:57

fuel additives FTL. dont use them on boosted cars.

if you have any type of methanol or coolant spray, inject it in your IC pipes.. your not supposed to put it in your fuel tank. unless im confused on which "methylated" your talking about

**Radar** · 8-3-07, 10:22

You have an FMU right? That is probably the lean spot (given the RPM you gave) when just crossing into boost. Very typical of FMU opperation and very damaging each time.

**turbociv920** · 8-3-07, 12:50

but even then it might just be an inadequate tune, and its running like [shizzle] and is not detonation... with 98 octane, its harder to knock than with the original 91 or 93

**Turk** · 8-3-07, 22:54

Quote:

Originally Posted by turbociv920

but even then it might just be an inadequate tune, and its running like [shizzle] and is not detonation... with 98 octane, its harder to knock than with the original 91 or 93

98 AUSSIE octane. That is bassicaly our highest pump rating here, (you see the odd 100). Im quite sure we use a different octane reading than you fellas. 98 is our premium and I think it is equal to your 92 or something. If I can remmember right

**Fitzyb** · 8-4-07, 1:37

Yup, our 98 is pretty much as high as it goes, even then is mainly additives that get it there, the 100 octane you see around gets its extra punch from ethanol (not something the KL really likes), and our lowest octane fuel is 91 for regular, then to 95 for premium, then 98 for ultimate/optimax depending where you get it from.

To go to 110 you would have to be using AVGAS, same thing as your local jumbo jet is using lol

But yeah, id be going with the FMU lagging problem, id fix that real quick

BleedingCopex · 9-4-07, 3:07

If you don't have an intercooler then this would be expected. Try water/meth injection to bring your intake temps down.

SixSick6 · 9-4-07, 3:22

Detonation is the sound your car makes shortly before you forgot or just don't take your foot of the accelerator. Not all detonation is bad or is enough to ruin an engine but definately needs to be fixed rather than driven on.

It sounds like a bag of BB's throuwn in your engine bay and makes a metallic ping sound. It's pretty distinct. You know, it's the sound you're hearing everyday.

**Kansas** · 9-4-07, 11:05

can you hear it over your turbo/sc/enginegonnablowup sound?

SixSick6 · 9-4-07, 21:18

If you're paying attention to it. It's easier to hear when you're listening for it-such as on a dyno. Much harder with road noise- such as street racing or on the highway. It's very distinct though.