which spark plugs ?

[sharkemir]

hello guys,
i have 1998 audi a3 1.8T (AGU).i've done big turbo upgrade with 2871.the car made around 400 hp but i got some problems with spark plugs.i use NGK PFR6Q spark plugs.but sometimes i feel some miss fire and i when put the spark plugs out ,they 're like black as coal.then i tried BKR7Es and the result was same as PFR6Qs and i've checked my A/F and its around 10.5-11.

so what do you use for your BT upgrade ? or any suggestions ?

 

[h17och]

denso ik22 are quite popular

 

[ibizacupra]

A/F of 10.5? is your soot issue
why so rich? your hurting power unless tuned to keep egts down.... thats too rich imho

 

[Cupra 200bhp]

My A/F sits about 13-14

 

[h17och]

i believe thats a little lean cupra_200bhp

full chat you want mid 11's to 12 iirc (been awhile since mine has displayed any info lol)

 

[DPJ]

i believe thats a little lean cupra_200bhp

eeek! I agree.


On plugs - Denso Iridium IK22 for me.

 

[ibizacupra]

My A/F sits about 13-14

thats the other side... of being spot on..
too lean for IHI... beware fella

 

[phil_m]

I have allways had the same problem with my AGU and the only plug i dont get missfire with is the standard NGK BKUR6ET-10.

Oh and it also runs rich.

Phil

 

[h17och]

hes not on ihi

gt2871r, matts car

 

[Cupra 200bhp]

thats the other side... of being spot on..
too lean for IHI... beware fella

As hooch says mines is GT28701R?? I will have to check what its like on full power, 13-14 is just normal driving! I'will have to double check when power is in place

Matt did say to me he got it mapped so it was over fuelling more to be on the safe side

 

[h17och]

well its defo not over fueling

 

[DPJ]

As hooch says mines is GT28701R?? I will have to check what its like on full power, 13-14 is just normal driving! I'will have to double check when power is in place
...........

Yes, normal driving, not on boost, all our cars should be running stoich - around 14:1. We're really talking about wide open throttle figure - full boost.

 

[Cupra 200bhp]

Brought the car to work this morning, had a little blast on full boost and it sits about 9-10?? Dont usually bring the car but it was bugging me

 

[sharkemir]

hello guys ,
as i said my af is around 10.5-11 on full boost ? is it really rich ? i thought these numbers are ok on full boost...anyway, i still couldn't find the solution for the spark plugs..i found some information about these kind of problems ,some people said that maybe the lambda sensor had broken...i'm gonna check lambda sensor..any other suggestions ?

 

[HTC]

I've heard that the plug gap can be too large on BT setups, or is that just when you are running high boost?

Would closing the gap a little help reduce miss-fires?

 

[DPJ]

I'd be looking elsewhere than the plug for the source of the misfires unless they were knackered or you were running a huge gap.

 

[ibizacupra]

hes not on ihi

gt2871r, matts car

no but the other guy is who posted lean afr

 

[ibizacupra]

hello guys ,
as i said my af is around 10.5-11 on full boost ? is it really rich ? i thought these numbers are ok on full boost...anyway, i still couldn't find the solution for the spark plugs..i found some information about these kind of problems ,some people said that maybe the lambda sensor had broken...i'm gonna check lambda sensor..any other suggestions ?

ignore the lambda thing if your figures are on boost...... as there is no lambda control on boost, its the map which controls it. idle, cruising are when lambda is controlling. Does it read 14-15 on idle?

 

[ibizacupra]

Brought the car to work this morning, had a little blast on full boost and it sits about 9-10?? Dont usually bring the car but it was bugging me

you have fueling of 9:1 to 10:1 ??
seriously rich.

unisettings/lemmiwinks it back down fella.. It will go better too.
12 to 12.5 to one is lbt afr.

you can adjustr this yourself progressively if you have a vagcom cable and download the aforementioned adjustment programmes.
You have'nt stuck a 4bar fpr in there have you, when it was maybe mapped for 3bar?