Spark plug question

[JMA-RUF]

What kind of plugs are you guys running in your modded EFI'd street motors?

[wanabe911 owner]

I asked my tech this today and he said use 930 spec plugs. Anyone care to chime in?

[JMA-RUF]

They're too cold and expensive for street use... BTDT

[David]

NGK Iridiums, BPR8ES and DPR8EA (or something like that)

[fredmeister]

Are you tracking it or DE days.....this may make a difference to run a cooler plug than for street.
Good question.

[JMA-RUF]

My understanding is if it's purely for street use, then a warmer plug is OK to use as it won't foul as quickly.

For track events, definitely use a 3 or 4 heat range.

Just curious to know what range you guys are using on the street without fouling.

[mppickett]

Originally Posted by JMA-RUF

My understanding is if it's purely for street use, then a warmer plug is OK to use as it won't foul as quickly.

For track events, definitely use a 3 or 4 heat range.

Just curious to know what range you guys are using on the street without fouling.

I've been running for a couple of years of street use on NGK BKR7EIX plugs with no fouling. This is one range colder than stock 993 turbo OEM. Here are my basic specs:
- 1978 930 3.3 engine
- twin-plugged, ported, polished & flowed heads
- dual 6 plug EDIS ignition
- 8:1 compression ratio
- 964 cams
- 50# injectors
- K27-7200 turbo
- B&B headers
- Megasquirt II v3.0