Spark Plugs : which ones to use 4age ?

[IBMFD3S]

bought BCPR5EY NGK Spark Plugs

[SutteR]

I recently ordered a set of BKR6EIX for the smallport but forgot to mention that I need 0.8mm gap. They've sent me the BKR6EIX-11...

What are the effects of using this with bigger gap? AFAIK the gap cannot be adjusted on the Iridium plugs.

[Sgonzalez]

Which ones do I need for a silvertop turbo??? I put spare ones that I had in a 4g92 engine and the silvertop ate them in 2 weeks!!!

[jondee86]

@SutteR
The larger gap is unlikely to make any noticeable difference if your
ignition system is in good condition. AFAIK a wider gap can actually
improve charge firing, but it is a bit more difficult for the spark to jump
the gap. This can contribute to misfiring under high load, high rpm
operation... hardly an issue unless you are racing

@Sgonzalez
Since there was no factory silvertop turbo, there are no plug listings.
Best bet is to use the OEM plug recommended for the base engine and
go one heat range colder. A turbo engine just runs hotter, so you need
a colder plug. Using a plug from another engine is not a wise choice, as
the plug design may be different, possibly leading to overheating of the
plug tip... and a short plug life....

Cheers... jondee86

[jamiemirror]

jondee86 Wrote:@Sgonzalez
Since there was no factory silvertop turbo, there are no plug listings.
Best bet is to use the OEM plug recommended for the base engine and
go one heat range colder. A turbo engine just runs hotter, so you need
a colder plug. Using a plug from another engine is not a wise choice, as
the plug design may be different, possibly leading to overheating of the
plug tip... and a short plug life....

Cheers... jondee86

What about plugs for 4AGZE ?

[jondee86]

Typically a silvertop turbo has high compression and low boost, so one
heat range colder on the standard plug should be fine for normal
everyday use. Maybe go two ranges colder on race day

However, 4AGZE => 4AGTE conversions will typically run 15 psi or even
higher boost, so plug choice gets a bit more complicated. You can try
experimenting with other plugs until you find one that works for you. If
it can ignite the mixture reliably under all boost conditions, and the heat
range falls somewhere between fouling and vapourising the electrode,
then you are good to go

Best to talk to people who are running similar setups, and have a read
of this link to get a few ideas :

http://www.lextreme.com/sparkplug.html

The silvertop head design is quite different from the 16V GZE design,
so you can't take it for granted that one will suit the other.

Cheers... jondee86

[Sgonzalez]

THANKS JONDEE86 AND JAMIEMIRROR FOR YOUR ADVICE, THE CAR FUNS 11 PSI OF BOOST!!! AND YES., THE CAR HAS A PIROMETER AND IT GETS REALLY HOT INSIDE DE ENGINE

[jamiemirror]

You have EGT ? Do you have some data logged ?

[SutteR]

jondee86 Wrote:@SutteR
The larger gap is unlikely to make any noticeable difference if your
ignition system is in good condition. AFAIK a wider gap can actually
improve charge firing, but it is a bit more difficult for the spark to jump
the gap. This can contribute to misfiring under high load, high rpm
operation... hardly an issue unless you are racing

Thanks. Actually I use the engine for drifting so there might be some trouble for me using these?

[Sgonzalez]

jamiemirror Wrote:You have EGT ? Do you have some data logged ?

It is an analog pyrometer!!