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So I Changed My Spark Plugs For The First Time ...

Torques

By Torques,
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SteveL Mentor

SteveL

Posted
Posted

Those champion plugs look much like I'd expect a standard set to after quite a few k's - rounding of the centre electrode due to erosion, which also increases the gap. There seems to be bit of variation in combustion between cylinders but that might be due to the increasing gap....also could just be the photo. In any event, the amount of k's to produce the same erosion in a set of platinum plugs should be considerably greater (assuming normal combustion).

One possible common thing here is fuel - what do you run in these cars over there ??

Torques Mentor

Torques

Posted
  • Author
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Those champion plugs look much like I'd expect a standard set to after quite a few k's - rounding of the centre electrode due to erosion, which also increases the gap. There seems to be bit of variation in combustion between cylinders but that might be due to the increasing gap....also could just be the photo. In any event, the amount of k's to produce the same erosion in a set of platinum plugs should be considerably greater (assuming normal combustion).

One possible common thing here is fuel - what do you run in these cars over there ??

Hi ...

Mostly 95 octane ... pump fuel.

Then there is 100 octane ultimate, but it's quite pricey.

I have not tried 100 octane yet, but will check it out once my gas tank is nearly empty.

Wacky Dee Veteran

Wacky Dee

Posted
Posted
I now have installed these NGK copper plugs (shame on me) and I have a slight misfire at idle (at least I think it's misfire)

And I'm under the impression that the car ran better with the AutoLite Platinum plugs. (though I have not fully tested)

Cheers from rainy London :)

Were they the .8mm pregapped ones ?? I had misfire at idle too with .8mm. Regapped them to 1mm and no more misfire at any rpm... If you can't be bothered regapping, might be easier/cheaper just to buy a new set (what is it like 10 euro for 6?) of the ones that come with 1.1mm gap and try those, I suspect they'll work just fine if the old ones were 1.5mm.

SteveL Mentor

SteveL

Posted
Posted
Mostly 95 octane ... pump fuel.

Then there is 100 octane ultimate, but it's quite pricey.

95 is probably a bit on the low side, but should be OK as long as you don't push it too hard and are running stock boost and timing. AFAIA these cars are designed to run on around 100 octane Jap fuel so the further you are away from that standard the more likely damage is to occur. Anyway, may not be the total answer for the plug damage you have, but possibly a contributing factor.

Torques Mentor

Torques

Posted
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Posted
95 is probably a bit on the low side, but should be OK as long as you don't push it too hard and are running stock boost and timing. AFAIA these cars are designed to run on around 100 octane Jap fuel so the further you are away from that standard the more likely damage is to occur. Anyway, may not be the total answer for the plug damage you have, but possibly a contributing factor.

Yep ... they are designed for 100, but the knock sensor helps keeping low octane usable.

What fuel do you driver over there?

And how expensive is gas in Oz?

Cheers ..

GTR-N1 Grand Master

GTR-N1

Posted
Posted

GDay Andrew!

We use 98 RON fuel here and it's cheaper than yours! In Sydney, it can be $1.29/l midweek and then go up 10c later in the week.

I'd try re-gapping the plugs as Delta-F said with your 100 octane and get back to us.

If the Kms travelled is suss, had you thought of changing your timing belt?

Cheers, T

Torques Mentor

Torques

Posted
  • Author
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GDay Andrew!

We use 98 RON fuel here and it's cheaper than yours! In Sydney, it can be $1.29/l midweek and then go up 10c later in the week.

I'd try re-gapping the plugs as Delta-F said with your 100 octane and get back to us.

If the Kms travelled is suss, had you thought of changing your timing belt?

Cheers, T

Hi Terry,

That's dirt cheap for 98 RON!

I'll come over to Oz then ... seems a good place for me anyway since I also have a dirtbike which I really would like to use...

As for the timing belt I have given it some thought already ..

I'd like having a look at the belt just to be sure ..

Is the cover easy to detach so the belt is exposed for checking?

As for the car:

The mileage seems suspiciously low but all the engine (serpentine) belts look like brand new.

Then there are the tires.

The manufacturing date for the tires seems to be 01/2001 and they're some expensive Japanese ones (forgot the name)

However the thread is at 85% ..

But one thing is for sure, it has been garaged since the paint is in good nick.

Cheers! :blush:

SteveL Mentor

SteveL

Posted
Posted

If the car is running fine and your happy with it, then I'd just drive and enjoy. The issue with the plugs will probably remain a mystery.

In terms of fuel, you should run as close to what is recommended as possible. 98 is the minimum I would run, but lower is possible, just take it easy. One thing - don't rely on the knock sensor to do your tuning for you (so to speak)....it's not designed for that.

GTR-N1 Grand Master

GTR-N1

Posted
Posted
That's dirt cheap for 98 RON!

I'll come over to Oz then ... seems a good place for me anyway since I also have a dirtbike which I really would like to use...

Yes Andrew, I believe your petrol costs are about 33% above ours for the same grade.

I suspect that the North Sea Oil has been milk by the Norwegians whilst the English are asleep! :down:

That's why they won't join the EU!

And that's my version of a Conspiracy Theory anyway.

Look some of us up when in Oz eh?

Happy to know your car's in good nick. :ermm:

CatsEyes Enthusiast

CatsEyes

Posted
Posted
Yes Andrew, I believe your petrol costs are about 33% above ours for the same grade.

Actually, I think it's even pricier than that. It's over a pound there at present, I think, for regular. Which is about AU$1.90 at the current exchange rate.

Torques Mentor

Torques

Posted
  • Author
Posted
Were they the .8mm pregapped ones ?? I had misfire at idle too with .8mm. Regapped them to 1mm and no more misfire at any rpm... If you can't be bothered regapping, might be easier/cheaper just to buy a new set (what is it like 10 euro for 6?) of the ones that come with 1.1mm gap and try those, I suspect they'll work just fine if the old ones were 1.5mm.

Well ... I see what I can do.

Right now I'm glad I got the bonnet closed :)

But I guess I need to regap the plugs to 1-1.1 ..

:P

Torques Mentor

Torques

Posted
  • Author
Posted
Actually, I think it's even pricier than that. It's over a pound there at present, I think, for regular. Which is about AU$1.90 at the current exchange rate.

Right ... and given the current rate of exchange it is more like AU$2.20 for 100 octane ..

:P

GTR-N1 Grand Master

GTR-N1

Posted
Posted
Right ... and given the current rate of exchange it is more like AU$2.20 for 100 octane ..

:P

To us Sydney-fellah-talk, that means we can pay for the fuel from Sydney to the base of Macquarie Pass and then go UP & DOWN Macquarie Pass for nicks!!! So that's what we save in our fuel costs to yours lolz

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