hey guys, im running a D16y8 with an FMU, walbro 255 in tank pump, 93 octane all the time, a 14b (eclipse) turbo, a side mount intercooler that is front mounts where the a/c stuff normally goes, 290cc injectors, buddy club spec 2 exhaust - running about 10psi... whenever i boost i hear a soft crackling sound from my engine bay, is sounds like its more from the drivers side of it, but i have know clue... it only happens when under boost at high RPM's, starting around like 5k... i have no clue whether its detonation, an exhaust leak or anything... ive never heard this in anyones car awell.. any info would be appreciated...

oh and, when i retard my timing with the distributor cap all the way it seems to go away, but i dont know if thats because my car is then slow as ****, and its not putting as much exhaust output or something that may be leaking... i have ******* no clue, im just trying to figure out what the hell is going on...

 

That sounds like detonation. Does it dounds like marbles in a metal can gettin shook around. check you r plugs for signs of leaning and detonation. If you retard the ignition and the sound goes away it prolly means that you did not retard it enough. Set it to were you don't hear it anymore then like 2 or threee more degrees to be safe. GL and don't keeping driving it like that you'll blow something

 

the wierd thing is is that its kinda of a soft sound... like no pinging or anything, kinda almost like a faint sound of tin foil being crinkled... i dont know its weird, i change my NGK BCPRes7-11's or whatever the part number is every 2,000 miles... the plugs usually look fine when i replace them... i also gap them to .30

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fresh pizza guy &raquo;</TD></TR><TR><TD CLASS="quote">the wierd thing is is that its kinda of a soft sound... like no pinging or anything, kinda almost like a faint sound of tin foil being crinkled... i </TD></TR></TABLE>

detonation can definately sound like that. it doesn't always sound like "ping ping ping" (even though it can). Sometimes it can just sound like ticking... or what you describe...

 

looks like you are getting detonation. you need a tune, i would not trust the fmu with anything over 5psi or so....if you keep that up, say goodbye to the motor

 

sounds like detonation. time to get some fuel managment!

 

well im willing to get some form of fuel managment, im kinda going towards a VAFC just so i can still pass inspection without trouble, but i can also get uberdata for about the same price... need some suggestions...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fresh pizza guy &raquo;</TD></TR><TR><TD CLASS="quote">well im willing to get some form of fuel managment, im kinda going towards a VAFC just so i can still pass inspection without trouble, but i can also get uberdata for about the same price... need some suggestions... </TD></TR></TABLE>

dont run the hack, its not much better than the fmu

definately go with uberdata, you will not be disappointed

 

um 10 psi with 290 cc injectors. not good at all

 

well when it was cold out i was running 14-16psi on 230cc injectors and it ran awesome.

 

what type of wastegate do you have? sounds like it might be the wastegate gasket. if thats your problem, its an easy fix. get a firering and you should be good to go.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Boostedcivicsi &raquo;</TD></TR><TR><TD CLASS="quote">what type of wastegate do you have? sounds like it might be the wastegate gasket. if thats your problem, its an easy fix. get a firering and you should be good to go.</TD></TR></TABLE>
he has an internal wastegate. It is detonation Erol. I've heard the same thing from my y8 before. Time for uber

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">
he has an internal wastegate. It is detonation Erol. I've heard the same thing from my y8 before. Time for uber </TD></TR></TABLE>

yes it is... currently searching for a chipped ecu...

 

def detonation. sound kinda like a pressure cooker? that is how mine was.

 

i had the same thing with my z6. it was hard to me to describe the sound, cause it was sooo faint. mine was also accompanied by a slight hesitation. problem is that i was running 11.5 a/f when i was hearing the noise. see if u cant borrow a wideband from someone for like 5 minutes and just check your a/f. then if its bad turn the boost down and go uberdata.

 

yeah ive decided to get uberdata... now im just trying to hunt down some 450's. and a chipped p28...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blackeg &raquo;</TD></TR><TR><TD CLASS="quote">i had the same thing with my z6. it was hard to me to describe the sound, cause it was sooo faint. mine was also accompanied by a slight hesitation. problem is that i was running 11.5 a/f when i was hearing the noise. see if u cant borrow a wideband from someone for like 5 minutes and just check your a/f. then if its bad turn the boost down and go uberdata.</TD></TR></TABLE>
sounds like the problem i've had with my y8. Last year once it got cooler out i could hit a straight 11.5:1 afr with very conservative timing and still be hearing the sound. Now I have an external wastegate so i don't even know if its there anymore. Strangely though there are no signs of detonation on my pistons, i got no blowby(messed up block), and my plugs after a WOT pull looked perfect. Tanish brown color with NO marks of detonation.

 

conversion harness has been purchased... now looking for a p28 and some injectors!!

 

Im sure if you've heard that "crinkling" sound a few times and kept pushing the car, you've already done some damage to your pistons. Just some advise, do a compression test and monitor your oil level. Your ringlands may have been cracked.

 

SOHC_MShue, we definately had the exact same thing. my plugs were perfect and no blowby(my catchcan was bone dry)

fresh pizza guy, good start on the conversion harness. as for injectors i used dsm's for my last setup and they worked fine. this time around i bought rc 440's, but they were like 4x the price. the uberdata is easy to work with when using 450/440 cc injectors(something like 10% fuel is 1 full a/f ratio point).

muckman also offers good advice, do a quick compression check and keep an eye for any signs of blowby. good luck to you

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by blackeg &raquo;</TD></TR><TR><TD CLASS="quote">SOHC_MShue, we definately had the exact same thing. my plugs were perfect and no blowby(my catchcan was bone dry)

fresh pizza guy, good start on the conversion harness. as for injectors i used dsm's for my last setup and they worked fine. this time around i bought rc 440's, but they were like 4x the price. the uberdata is easy to work with when using 450/440 cc injectors(something like 10% fuel is 1 full a/f ratio point).

muckman also offers good advice, do a quick compression check and keep an eye for any signs of blowby. good luck to you </TD></TR></TABLE>
man i wonder if it has anything to do with my dsm injectors. I even tried switching over to another set without any luck. Are your new rc's on the same motor you had the 450's on? I am wondering if it is something to do with my wiring...like maybe one of the injector wires was loose causing one cylinder to lean out and not show up in the afr?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by SOHC_MShue &raquo;</TD></TR><TR><TD CLASS="quote">
man i wonder if it has anything to do with my dsm injectors. I even tried switching over to another set without any luck. Are your new rc's on the same motor you had the 450's on? I am wondering if it is something to do with my wiring...like maybe one of the injector wires was loose causing one cylinder to lean out and not show up in the afr? </TD></TR></TABLE>

No you would have already melted or cracked the piston by now. Injector failure = almost instant problems.

 

well maybe its just slight failure or something...i dunno