33 replies to this topic

[850 LongBeach]

Well I just recently changed my spark plugs to the same exact kind Champion Copper RC12YC I gapped at .025 I believe my old ones were gapped at .026

Im running about 17-18 psi


My first run after I changed the plugs it hauled crazzzy ALL GLORY TO THE HYPNOTOAD at 18 psi with no detonation at all, but then hours later It started detonating

AF/R's are in 11-12s

At anywhere above 12-13 psi I start to detonate

Anyone have any reccomendations?

Im thinking maybe bad gas? I just spent about 15$ at a mobil about 3 hours before the first run,but there was still gas in the tank ,

91 is all we get in cali but It usually does fine...Im thinking maybe a switch to chevron might do my car good.

Please shed your ideas thanks guys

[850 LongBeach]

Admin I have moved to fwd, please delete
sorry guys

[PsychoWagon]

You shouldn't have to gap @ 17-18psi on a 19t. I've said it many times, use oem plugs it will probably fix your problem, secondly, if you are going to gap, .025 is way too small. .027-.028 on oem plugs with the 19t and have a nice day. Take your plugs out and take a look at the electrode on the plug be all melted away

[Cal3thousand]

PsychoWagon, on 21 October 2009 - 11:11 PM, said:

You shouldn't have to gap @ 17-18psi on a 19t. I've said it many times, use oem plugs it will probably fix your problem, secondly, if you are going to gap, .025 is way too small. .027-.028 on oem plugs with the 19t and have a nice day. Take your plugs out and take a look at the electrode on the plug be all melted away

Agreed,

you shouldn't be gapping down unless you had spark blowout. In fact, you should use the widest gap that won't blowout at your boost level.

But, there are plenty that gap down lower... But in the end, a 15G tune on a 19T... what would you really expect?? what injectors are you running?

[850 LongBeach]

PsychoWagon, on 21 October 2009 - 11:11 PM, said:

You shouldn't have to gap @ 17-18psi on a 19t. I've said it many times, use oem plugs it will probably fix your problem, secondly, if you are going to gap, .025 is way too small. .027-.028 on oem plugs with the 19t and have a nice day. Take your plugs out and take a look at the electrode on the plug be all melted away

YOU ARE 100% RIGHT, I had the other plugs in for only about 2k-3k miles and the the contact arm was all white and blistered but the electrode was fine

Cal3thousand, on 21 October 2009 - 11:14 PM, said:

Agreed,

you shouldn't be gapping down unless you had spark blowout. In fact, you should use the widest gap that won't blowout at your boost level.

But, there are plenty that gap down lower... But in the end, a 15G tune on a 19T... what would you really expect?? what injectors are you running?

Whoa dont say that, It has been running nothing but good lately, this is user error,


im going to fix the gap before I go to school today, im letting the engine cool down...

Let you know what happens later for sure

Oh and stock oranges

The Champion RC12YC is listed in Haynes manual as OEM as well

[PsychoWagon]

Quote

The Champion RC12YC is listed in Haynes

Haynes is the other problem

If the plugs are already screwed regapping may not do anything. I would get new plugs and go to 0.028 and see from there.

[850 LongBeach]

PsychoWagon, on 21 October 2009 - 11:23 PM, said:

Haynes is the other problem

If the plugs are already screwed regapping may not do anything. I would get new plugs and go to 0.028 and see from there.

I havent looked but they have only been in for one day so im not planning on buying new ones

[HayaCruza]

PsychoWagon, on 21 October 2009 - 11:23 PM, said:

Haynes is the other problem

If the plugs are already screwed regapping may not do anything. I would get new plugs and go to 0.028 and see from there.

Everyone keeps saying use OEM plugs but look at your owners manual, what does that say:

My 1997 850 owners manuals says:
For Turbocharged - Champion RC7GYC (or equivalent)

Notice that it does not say Volvo PN XXXXXX, it actually says CHAMPION!

[Black Betty]

I have coppers gapped to .022 I doubt the gap is the problem, the only "problem" I have is a backfire whenever I push it

[Fake-R]

I'm using OEM plugs, gapped to .25, with no issues. Watch that detonation, that will kill your rods.

[Black Betty]

Fake-R, on 22 October 2009 - 01:20 AM, said:

I'm using OEM plugs, gapped to .25, with no issues. Watch that detonation, that will kill your rods.

+1 figure that shit out LB as much as I hate it make me look like an idiot and keep your rods straight sounds like you actually found a setup that works well with the 19t

[lookforjoe]

Are you sure you don't mean blowout?

Detonation would probably have killed your motor by now, at those boost levels.

[shaun]

850 LongBeach, on 21 October 2009 - 10:49 PM, said:

Well I just recently changed my spark plugs to the same exact kind Champion Copper RC12YC I gapped at .025 I believe my old ones were gapped at .026

Im running about 17-18 psi


My first run after I changed the plugs it hauled crazzzy ALL GLORY TO THE HYPNOTOAD at 18 psi with no detonation at all, but then hours later It started detonating

AF/R's are in 11-12s

At anywhere above 12-13 psi I start to detonate

Anyone have any reccomendations?

Im thinking maybe bad gas? I just spent about 15$ at a mobil about 3 hours before the first run,but there was still gas in the tank ,


91 is all we get in cali but It usually does fine...Im thinking maybe a switch to chevron might do my car good.

Please shed your ideas thanks guys

\\


that is a cold plug. my car ran like stuff on 9y when I could not get 7y in a pinch. 12y could foul quickly. you said you are not willing to by new plus since these are new. 10 bucks? really? you car is super rad but the right temperature plugs are really important. are you sure you took out 12s?

[850 LongBeach]

shaun, on 22 October 2009 - 03:57 AM, said:

\\


that is a cold plug. my car ran like stuff on 9y when I could not get 7y in a pinch. 12y could foul quickly. you said you are not willing to by new plus since these are new. 10 bucks? really? you car is super rad but the right temperature plugs are really important. are you sure you took out 12s?

I live in a different climate than you...Im running a different turbo on a different set up and yes im sure I took out 12's

[Zaitz]

lookforjoe, on 22 October 2009 - 03:21 AM, said:

Are you sure you don't mean blowout?

Detonation would probably have killed your motor by now, at those boost levels.

That's what I was thinking.

[Boost3237]

PsychoWagon, on 21 October 2009 - 11:11 PM, said:

You shouldn't have to gap @ 17-18psi on a 19t. I've said it many times, use oem plugs it will probably fix your problem, secondly, if you are going to gap, .025 is way too small. .027-.028 on oem plugs with the 19t and have a nice day. Take your plugs out and take a look at the electrode on the plug be all melted away

I'm still on the fence here, I was gapped at .025 for a long time, then I backed off to .028 and I honnestly did not notice a difference.

[PsychoWagon]

Quote

I live in a different climate than you...Im running a different turbo on a different set up and yes im sure I took out 12's

climate has nothing to do with plug heat range... the temperature in the combustion chamber has everything to do with it. whether it be +40c or -40c outside, your combustion temperatures don't vary all that much.

[ozzimark]

PsychoWagon, on 22 October 2009 - 11:23 PM, said:

climate has nothing to do with plug heat range... the temperature in the combustion chamber has everything to do with it. whether it be +40c or -40c outside, your combustion temperatures don't vary all that much.

How come you're the only one without a -1 or -2 in this thread right now?

Also, manual calls for 7 I believe. You put in 12. 12 is a much higher heat range than 7, thus the plugs will run much hotter. Gap isn't the issue, your spark plugs are turning into glow plugs, thus the detonation.

[shaun]

ozzimark, on 23 October 2009 - 12:01 AM, said:

How come you're the only one without a -1 or -2 in this thread right now?

Also, manual calls for 7 I believe. You put in 12. 12 is a much higher heat range than 7, thus the plugs will run much hotter. Gap isn't the issue, your spark plugs are turning into glow plugs, thus the detonation.

I gave up when sunset climate zones came into the conversation, but FYI the tempo range numbering system on plugs is counter intuitive. The higher number is colder

http://www.gsparkplu...ras/heat_range/

http://www.nagca.com...arkplugheat.htm

the OP might benefit from from a plug one step colder or something with his mods, but not 5. Seems to me like 5 steps colder would foul quickly, and that would very likely cause weak, none, or blown out spark as lookforjoe stated. If it were my car with those plugs and that problem i would get the right plugs in it. The owners manual states y7.

[ozzimark]

Champions are backwards from NGK. Higher = hotter. Same with Bosch

http://www.champions...yImages/722.jpg

Just checked my manual, which may be different from LongBeach's car, but I doubt it. It calls for a Bosch 7 or Champion 9. 12 is WAY too hot for a turbo whiteblock application, no matter how you look at it.