I have been having a lot of detonation problems with my car lately. First you can look at my list of mods:

JDM Gen 2 B16a - 10.7:1 Compression
Stock B16a Gen 2 cams
JDM p30 ECU
VAFC (untuned apart from adding some fuel at 4500 to 5800rpm VTEC engagement as it runs lean there)
2 layer headgasket
Ported & polished head
Bored throttle body
Short ram intake
4-2-1 header
2.25" mandrel bent exhaust with N1 muffler.

Problem: Initially i had set the ignition base timing to 18 degrees via the distributor. Drove around and noticed that it was pinging a little under load so i wind the timing back a couple of degrees to 16 degrees. I run with that setting for a while. Maybe i didnt notice but today i noticed some pinging at low rpm. Say travelling in 3rd gear at around 2500rpm. I would just put my foot down a little to around 30% throttle as you do to accelerate and it pings noticeable. Now WTF my motor is not hardcore modified so i thought the ECU would handle these changes... unless the port and polish severly increases air flow making the car run lean.

So i think my car is running lean because, my timing is at stock 16 degrees. But i thought the o2 sensor would adjust my A/F accordingly while in part throttle? Im confused!

 

yea man i would like to hear more on this...my lsvtec does the same thing...i got my timing at 14degrees.....somebody help us out???????

 

???

 

try using a higher octane and see if you notice any ping

 

im useing 91...its the highets we got here

 

you could have a hot spot somewhere in the combustion chamber causing preignition

 

Pick up a set of NGK BKR7E-11s, you might be running too hot of a plug.

And get it tuned... Whats your fuel pressure at?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVTEC 91 Civic &raquo;</TD></TR><TR><TD CLASS="quote">Pick up a set of NGK plugs with a heat range of 7...

And get it tuned.</TD></TR></TABLE>

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by LSVTEC 91 Civic &raquo;</TD></TR><TR><TD CLASS="quote">Pick up a set of NGK BKR7E-11s, you might be running too hot of a plug.</TD></TR></TABLE>

when my cometic headgasket arrives tomorrow, i can finally finish bulding my 00 Si. before i fire it up, i want to make sure i got the right plugs.

i got the ngk BKR6EIX-11 plugs. what's the difference? i'm using ctr pistons. do i want a 'hotter' plug, or one that is not so 'hot'? what is the difference between the plugs i got and the NGK BKR7E-11s mentioned above?

thanks!!!

&lt;edit&gt;i just realized - i'm not trying to thread-jack or anything. i think this is close enough on the same topic that the answers would be educational for all. ok bye.&lt;/edit&gt;

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by nissanjon &raquo;</TD></TR><TR><TD CLASS="quote">when my cometic headgasket arrives tomorrow, i can finally finish bulding my 00 Si. before i fire it up, i want to make sure i got the right plugs.

i got the ngk BKR6EIX-11 plugs. what's the difference? i'm using ctr pistons. do i want a 'hotter' plug, or one that is not so 'hot'? what is the difference between the plugs i got and the NGK BKR7E-11s mentioned above?

thanks!!!

&lt;edit&gt;i just realized - i'm not trying to thread-jack or anything. i think this is close enough on the same topic that the answers would be educational for all. ok bye.&lt;/edit&gt;</TD></TR></TABLE>

Yes, you want a colder plug, the higher the number, the colder the plug. I'm running NGK V-Power Racing plugs, they're 8's (NGK Stock number 4554), this is in my High comp LSVTEC. The difference between those two plugs, the 6EIX is an Iridium plug with a heat range of 6, and the BKR7E-11 is a copper plug with a heat range of 7.

Copper NGKs &gt; *

 

i got my ngk's at Napa Auto. I'm on napaonline.com right now and I can find a lot of NGK plugs for a 2000 Si. Some have a .044" gap, some a .052" gap, some say g-power platinum, some say iridium, some say laser platinum, heck some just say spark plug. They range from $1.89-$12.69 each. There are some V Powers, but they do not say "Racing" (those are $2.59 each).

I'm lost. I plan on returning the way-too-hot plugs, especially since i bought 8 and they are like $8.49 each. I'd like to be able to get the right ones from the same place but I want to make sure I'm asking for the right ones. Can someone please clear this up for me? How much should I expect to pay for the plug you recommended for the ctr pistons? THanks!

 

i was getting 9's for like 15 bux a set. that ***** way too expensive...

remember any oil/coolant in the combustion will make it detonate

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by johnzm &raquo;</TD></TR><TR><TD CLASS="quote">i was getting 9's for like 15 bux a set. that ***** way too expensive...

remember any oil/coolant in the combustion will make it detonate </TD></TR></TABLE>

cool - do you have a part number for those? thnks!

 

My plugs are what the service manual suggests NGK BKR-6E-N-11

Its just weird how im pinging on 16deg timing. The fuel im using is 98 octane in New Zealand which i think is equivalent to 91 in the US.

Yeah so its either the timing or running lean. I will check the timing again soon.

 

how can 98 octane in zealand be like 91 octane in america.

octane is octane!

you've got much higher octane

 

are you sure? the lowest we have is 91 RON then 96 RON then 98 RON.

Yeah hmm

 

Oil/coolant ===&gt; detonates!!!

Well, i think that is pretty true. i have a leak in my plug seal, and i am having some pinging problem. Had it tuned few months back and it was sweet, but noticed oil in my plug #1. Just don't have the time to get it done.

let me see if it stops my pinging. i am using premium gas from shell - V-power. A better addictive with 98 octane and i still **** with pings!

 

tianporn, you're 100% right that 98 RON is not 98 R+M/2 (US- style) Ask google "gasoline faq" if you want a better explanation.

I'd be inclined to say that tuning is the answer to your problems. The only time I've ever had much of a problem with low-end pinging was a GSR motor w/ CTR pistons and a 2 layer gasket. Depending on who you ask, that's around 13.0:1 - 13.5:1 compression. It was tricky to get that motor to run on 93 octane R+M/2, but it was doable. You *HAVE* to disable the O2 sensor. You *HAVE* to run the motor slightly richer in mid-vac - closer to 13.0 than the normal 13.7-14.0 I run. You *HAVE* to pull additional timing out of the spark map. The 400-600 mbar region plays a large role in transient state / tip-in detonation. If you can make it up above 4000 RPM w/o pinging, you're generally in good shape. Hope that helps.

 

.....the jdm ecu is for much higher octane than we have at the pump here.

You will need to chip that ecu for hondata/ uberdata/ crome/ neptune, etc and actually TUNE it.

 

Yeah i can't do much i guess with just a VAFC and adjusting base timing with the distributor.

Good explanation blundar but im only running stock block with 2 layer headgasket with compression around 10.7:1. This is a very mild setup, not wild at all. I'd like to upgrade to Crome some day but currently do not have the time or resources to do that as its my daily hack. I might get a FPR and bump up the fuel pressure a little and pull back the base timing a degree or too to see if it helps... but im leaning towards a timing problem rather than a fueling problem.

Thanks for the help

 

Bump

Will check my plugs tonight.

If my plugs are black sooted then it means it an ignition problem which is causing the detonation right?

IF the plugs are white then its probably running a bit lean.

I actually hope its a fueling problem because it will be easier to fix...

 

i got a ???...what does pinging sounds like?? is it like whistle kinda??? cuz i have the same problem after i bent some valves.. but mine usually goes either 3rd gear, or 5th gear around 2,5k to 3 k slightly pressed on the gas pedal...i got it fixed and dynoed after 4 months i bended it..and still the same thing,...im running on hondata right now..need professional help

 

Nothing like a whistle. More like a can of rocks. Driving over LOTS of oak leaves also maybe..

 

so its more like a rattling noise??...

 

Yup hard to describe. Rocks rattling is how i would describe it. Its hard to pick up when you have a loud exhaust but after you put a silencer on and listen out for it, you will notice it.