spark plugs

[kylemrushall]

hi

i have ngk plugs in my sbc, i was just wondering if anyone has other makes fitted and there part numbers. My local autofactor could not cross reference them for some reason and he doesnt stock ngk.

thanks

[eliot]

what ngk plug did you have?

I have edelbrock ally heads and run ngk bkr5e which crosses to a champion rc14yc - although I should be running 1 or 2 stages colder because of the turbos.

[kylemrushall]

ngk r5671a-8 ??

thanks

[TuxMan]

Hi Kyle , bkr5e for me too !!

[kylemrushall]

TuxMan said:

Hi Kyle , bkr5e for me too !!

thanks simon

[eliot]

kylemrushall said:

ngk r5671a-8 ??

thanks

Crosses to a Champion C61C over at sparkplugs.co.uk

Main difference between that and a bkr5e yours is non projected tip.

[mike huddart]

Dear Kyle,
The R5671-A-8 is a race plug only supplied to the American market.
Dimensionally they are the same as the BKR5E but dont have the extended electrode. The big differance though is that your plugs have a heat range three stages colder than the 5,s There may be a good reason for this, you will have to find out.
I would have thought, though, that they are way too cold for road use and you are going to have fouling problems. We would normally only fit 8,s to a Chevy with over 12-1 compression for race only
I have some 7,s and the BK,s in 6
Regards Mike

[kylemrushall]

Thanks Mike, nice to hear from you.

you are spot on they got 'fouled' very quickly. I have fitted some DENSO plugs the same spec as the 5's and it seems a lot better. I have 11.3 to 1 comp ratio, which is to be honest a little higher than i wanted, do you think the 5's will be ok?? The engine is a 377 with a high lift cam etc 7400 max rpm. How you doing with the ACCEL systems??

Kyle

[eliot]

Good information Mike.
I've got notes stating the R5671A-7 can be used up to 15lbs of boost, so the -8's would seem very cold for a n/a motor. Perhaps try some bkr6's in it as a compromise. I'm using 5's with 7lbs of boost (taking my effective c/r from 9.23 to about 12:1 i think).

[BogBeast]

mike huddart said:

Dear Kyle,
The R5671-A-8 is a race plug only supplied to the American market.
Dimensionally they are the same as the BKR5E but dont have the extended electrode. The big differance though is that your plugs have a heat range three stages colder than the 5,s There may be a good reason for this, you will have to find out.
I would have thought, though, that they are way too cold for road use and you are going to have fouling problems. We would normally only fit 8,s to a Chevy with over 12-1 compression for race only
I have some 7,s and the BK,s in 6
Regards Mike

Hi Mike, Nice to see you on here.

You built my engine about 15 years ago - still going strong !