proper plugs for a stroker with GN1 heads and E85, 160s

[turbo nasty]

Racetronix

 

[brent lovett]

Awesome, thanks. What kind of power are you making?

 

[brent lovett]

Awesome, thanks. What kind of power are you making?

 

[BEATAV8]

So, is the consensus that on E85 a NGK heat range 8 is the best place to start? What if you're only in the 20-25 psi boost range? Also seems that people like gasketed plugs more than tapered. With NGK 13/16" wrench size seems very common. Do those fit in our heads?

Nope, need the small hex. 5/8"

An 8 doesn't foul out, so might as well run it even if you aren't pushing sky high boost.

 

[MNwe4]

Sounds good. Thanks for the reply. Also, not sure if Brent Lovett is asking me or the OP or someone else.

 

[MNwe4]

Turbo Nasty was right though, pump and hanger came from Racetronix. Sourced PTFE fuel lines and fittings from Summit.

 

[MNwe4]

Ok, curiosity is getting the best of me. Since Autolite 103 is what Champion recommended back in the day for GN1 heads and people say gasketed plugs are also ok to use on these heads the 3923 appears equivalent to a 103. For what it's worth the 103 has been a great street plug for me for years. Wanting to know how these plugs cross over to NGK here's what one of their tech people had to say:

"Thank you for your inquiry. We have three different reach plugs here, and we have to figure out which one you can use for your cylinder head.

Autolite 103 = NGK TR6 (.708 reach/ taper seat)
Autolite 3923 = NGK BKR7ES (.750 reach/ gasket seat)
And Buick Grand National shows to be a .460 reach/ taper seat."

So it would seem like an Autolite 3 heat range crosses to a 6-7 in NGK. The BCR8ES listed earlier would be nice to try, but isn't readily available as mentioned. I came across this yesterday at the auto parts store:

NGK BR7EF - https://www.summitracing.com/parts/ngk-3346

If you don't mind the tapered seat, wouldn't this be a great plug to try if you're not a really high boost? According to the parts store their system said it comes gapped at .028".

 

[MikeL.]

NGK-9 for strictly racing. Its cold so it wont last long, in my experience, with street miles on it.
NGK 7 or 8's for street duty and mild boost. This is on a stock cp setup.

 

[BEATAV8]

Ok, curiosity is getting the best of me. Since Autolite 103 is what Champion recommended back in the day for GN1 heads and people say gasketed plugs are also ok to use on these heads the 3923 appears equivalent to a 103. For what it's worth the 103 has been a great street plug for me for years. Wanting to know how these plugs cross over to NGK here's what one of their tech people had to say:

"Thank you for your inquiry. We have three different reach plugs here, and we have to figure out which one you can use for your cylinder head.

Autolite 103 = NGK TR6 (.708 reach/ taper seat)
Autolite 3923 = NGK BKR7ES (.750 reach/ gasket seat)
And Buick Grand National shows to be a .460 reach/ taper seat."

So it would seem like an Autolite 3 heat range crosses to a 6-7 in NGK. The BCR8ES listed earlier would be nice to try, but isn't readily available as mentioned. I came across this yesterday at the auto parts store:

NGK BR7EF - https://www.summitracing.com/parts/ngk-3346

If you don't mind the tapered seat, wouldn't this be a great plug to try if you're not a really high boost? According to the parts store their system said it comes gapped at .028".