Honda D Series Forum banner

1 - 16 of 16 Posts

·
Registered
Joined
·
629 Posts
Discussion Starter · #1 ·
alright guys, i know that i probably should post this in the engine management forum, but since the car is boosted, i figured more people that know turbo cars would see it in here.

The problem is as follows. About a month ago I put a new motor in my EK hatch. It has been running great, other than the fact that I can't figure why it detonates slightly at WOT. It isn't tuning, because i've back the timing way off, and it has sufficient fuel (around 12.5:1 afr). I'm at a loss. It only does it some of the time, mostly depending on weather. I've heard that excessive backpressure can cause these symptoms, is that a possibility? I have been planning on getting Kteller 3" for some time, because I know that my current crush bent setup isn't free flowing enough. I suppose i could unhook the downpipe to see if it solves the problem, but then i'm afraid that I won't be able to hear if anything major is happening with the motor.

If it would help, I could take a picture of the plugs. The signs of detonation aren't very obvious. The "soot" on the end of the plugs has just kind of flaked off in spots. There doesn't appear to be any major damage to the pistons (if any at all) from what I can tell, and my compression is still fine. With this being said, I'd like to solve the problem before my new bottom end takes a shit.

The setup is as follows for those who don't know my car.

d16y7 head
-slightly milled, ported and polished
-delta 272 regrind
-skunk2 valvetrain
-skunk2 intake mani
-b18c throttle body iirc
-AEM trutime cam gear to compensate for the head milling
d16a6 block
-block guard
-eagle h beams
-SRP pistons
-OEM bearings
-ARP head studs, blahblahblah
all of the following are going byebye as soon as i have the money to upgrade, the turbo kit is from my last setup
-Ported HF mani
-t3 .48/.54
-greddy fmic
-2in hot pipe, 2.5 cold
-turboXS RFL
+all other supporting mods (injectors, wideband, turbo timer and all that jazz)

annnd, to top it off, 2 1/4" crush bent piping with gutted cat, huge ass resonator and a fart cannon

any help or advice would be appreciated. I'd like everyone's opinions on different exhaust setups as well.

Thanks in advance, this website has always been very helpful.

-Steve
 

·
Registered
Joined
·
629 Posts
Discussion Starter · #2 ·
one more thing, the plugs that i'm running are NGK BKR7E's. The ground strap is normal in color, but has little sections of soot that appear to be chipped off, if that makes any sense, the electrode looks fine, and the ceramic part is slightly sooty. the base of the plug appears to be normal on all cylinders. I'm wondering if the heat range is incorrect.
 

·
Registered
94 civic si
Joined
·
613 Posts
is it hesitating? or can you hear it in the engine? you said you pulled a lot of timing, mechanical timing or ignition?
 

·
Registered
Joined
·
629 Posts
Discussion Starter · #4 ·
well, its slow as balls with the amount of ignition timing, but it isn't really hesitating....at least not bad. It just sounds like its detonating. I pulled the timing in crome.
 

·
Registered
87 Integra RS-T
Joined
·
162 Posts
if you do unhook the dp from the rest of the exhaust system, it shouldnt be TOO loud, so you may be able to hear it still.

But to be absolutly sure, make a det can, so can clearly hear the detonation with out the dp connected to the rest of the exhast system. If you dont hear it with a det can, then you know for sure the problem is your exhaust system.
 

·
Registered
Joined
·
2,192 Posts
id run it a little richer, down to 11.8-11.5 or so afr's what are your timing numbers? you only lose a few hp if any going down into the mid high 11's but gain a small buffer if any of the ecu corrections arent working correctly.

i had to get down to about 15* of timing at 12psi on my y7 to stop detonation.

how are you listening to the detonation?
 

·
Registered
Joined
·
629 Posts
Discussion Starter · #7 · (Edited)
i've heard of "det can's" before, but how exactly do you make one?

i could clearly hear it from inside the car. i suppose i could throw a little bit more fuel at it, but i don't want to if i don't have to. i'm at 18 degrees at right around 6 psi, which is all that i'm running right now. that's what doesn't make sense. at that low of boost it shouldn't be detonating. i tuned a buddies gsr turbo eg and we were running 24 degrees at 10psi and it wasn't detonating, even though they're higher compression! I'm truely stumped. My other motor didn't have this issue, but it was stock bore, and this motor is .020. I'm just going to unhook the dp, make a det can and see how it runs. fuck it.

thanks for your fast responses, and if you have anything else to throw in don't be shy :razz: its going to rain all weekend so i won't be doing anything until the first of the week :(

edit: is it possible that i'm just hearing things? maybe i should just go do a few pulls, pull these new plugs and take pictures.
 

·
Registered
Joined
·
2,192 Posts
i've heard of "det can's" before, but how exactly do you make one?


thanks for your fast responses.
thats what i use. it costs about 15-25 bucks to make and you can make it in under 30 min.

look on honda-tech and type in det can or det cans and a huge thread will show up. im not sure if one was made on here.
 

·
Registered
Joined
·
629 Posts
Discussion Starter · #9 ·
awesome, you guys are badass.


any other suggestions? has anyone else had the same thing happen?
 

·
Registered
Joined
·
371 Posts
Try 12:1-11:8 AFRs instead.

The Y7 head has a very small quench, you don't need a lot of timing at all. Pull more timing until you no longer hear any detonation. If you have detonation, you have too much timing, even if it seems like you've pulled a lot out.

I don't know if you're aware, but the Dseries do not like a lot of timing! Bseries on the other hand like more, so it's not unusual to have so much more timing on a Bseries than on our Ds.
 

·
Registered
Joined
·
629 Posts
Discussion Starter · #12 · (Edited)
well, i went ahead and unhooked the DP just to see how it would run. my buddy and i got bored :lol: it is running a LOT better now, and it isn't so loud that i can't hear the motor. the plugs aren't showing any signs of detonation now either. I can't wait until i get some c16 and crank the boost up :razz:
 

·
Registered
Joined
·
371 Posts
You must have been getting exhaust reversion in the high Rs or something, but be careful if that car was tuned with the crush bent exhaust chances are you're running lean!!!;)
 

·
Registered
Joined
·
629 Posts
Discussion Starter · #14 ·
i'm the one that tuned it :lol:

it was the exhaust, i just wanted to know if anyone else had ever had that happen.
 

·
Registered
Joined
·
371 Posts
Never really heard of it working that way. Detonation occurs (as I'm sure you know) for two reasons.

Hotspots and Bad Timing.

If it's hotspots you can normally just add more fuel and you'll have less problems with that. But normally too much timing is the culprit.

You sure that now that you're open downpipe you just can't hear the detonation anymore?!
 

·
Registered
Joined
·
2,192 Posts
Never really heard of it working that way. Detonation occurs (as I'm sure you know) for two reasons.

Hotspots and Bad Timing.

If it's hotspots you can normally just add more fuel and you'll have less problems with that. But normally too much timing is the culprit.

You sure that now that you're open downpipe you just can't hear the detonation anymore?!
reversion can make you detonate if the restriction is bad enough and your already on the limit of knock. you could be right, maybe he just cant hear it now..

time to make a det can!! its so cheap and easy!!!!
 
1 - 16 of 16 Posts
Top