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Hi Fellas,

I was recently having a few issues with my car with low power output. However, I change the spark plugs (Put NGK platinum ones) and the power was back up (wheels spings in 3rd gear :down: )

Anyway, 3 weeks of driving, the power is back down, had a look at the spark plugs, and they are fouled, yet again...

I cant keep forking out $150 every 3 weeks to change the spark plugs, so what do you guys suggest?

I have a built rb25/30 block, forged pistons, rods, the whole shabang. GT35r turbo, Autronic SM4.

Went to the tuner last week, AFR were perfect throughout so I am not too sure whats causing the fouling? Will I need to get hotter plugs? I am currently running the NGK PFR6G-11 5555 at 0.8 gap.

Not sure what heat rating these are.

Any suggestions are welcome.

CHeers fellas.

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Do you have any rich spots in your tune, even small events? i.e. just coming onto boost, or injection cut on deceleration?

Are you getting any misfires, especially on boost?

as i understand it, plugs foul cos of rich condition and/or lack of spark (not igniting the mix)

maybe something to do with the gap?

with 22psi (going by whats in your sig) you might need a colder plug. most people run 6s on stock engines/lower boost.

what did your tuner have to say?

good luck bro

what kind of driving do you do?

constant short trips (5mins or so to work i the morning) when the car is cold and not hitting boost can foul plugs pretty easily...

if this is the case take it out for a nice longer drive and boost it a bit... it should clear up.

otherwise, look at your tune again... most likely too much fuel somewhere.

plugs to use would be bcpr7es @ 0.8

what kind of driving do you do?

constant short trips (5mins or so to work i the morning) when the car is cold and not hitting boost can foul plugs pretty easily...

if this is the case take it out for a nice longer drive and boost it a bit... it should clear up.

otherwise, look at your tune again... most likely too much fuel somewhere.

plugs to use would be bcpr7es @ 0.8

Pretty much 5-10 min drives to work and back each day, car doesn't even get a chance to fully warm up.

As for these bcpr7es, what heat range should I get?

How long do these spark plugs generally last?

I wouldn't mind changing them once a month, anymore than that gets annoying....

Thanks for the input :P

Pretty much 5-10 min drives to work and back each day, car doesn't even get a chance to fully warm up.

As for these bcpr7es, what heat range should I get?

How long do these spark plugs generally last?

I wouldn't mind changing them once a month, anymore than that gets annoying....

Thanks for the input :P

Theres your answer, you need to trim the temp compensation.

bcpr7es, usually 7-12 months depending on driving Kms.

the 7 in the number IS the heat range

mine last 20,000ish with 300rwkw

if your car is always on cold start / idle then try giving it a good run and boosting it for a while and see if the plugs clean up a bit.

if they do then you know which part of your tune has too much fuel

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