This should be my last damn question before getting this thing back in the vehicle (still plan on dropping the transmission/T-case in order to rebuild the latter, clean everything, and get the wiring harnesses installed neatly)...
My 4.2 mini-stroker is running a ~10.3:1 static compression ratio with a somewhat mild cam (slightly-modified Comp 68-201-4, if I'm not mistaken). Should I plan on running stock plugs, or something cooler? I'm guessing the former seeing as I can't find any discussion of the topic outside the scope of "normal" strokers (4.6+).
Thanks in advance.
4.2 mini-stroker spark plug temperature?
-
- Noob
- Posts: 15
- Joined: December 9th, 2017, 9:40 am
- Vehicle Year: 2001
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
-
- Strong Poster
- Posts: 891
- Joined: August 15th, 2009, 1:27 am
- Stroker Displacement: 4.7
- Vehicle Year: 2000
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
Re: 4.2 mini-stroker spark plug temperature?
Whichever spark plug you choose just make sure you’re dropping down a couple heat ranges
-
- Noob
- Posts: 15
- Joined: December 9th, 2017, 9:40 am
- Vehicle Year: 2001
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
Re: 4.2 mini-stroker spark plug temperature?
As always, thanks Russ! What’s the primary reason behind this? Compression ratio increase (dynamic or static), displacement increase, or something else?
- Cheromaniac
- I live here
- Posts: 3186
- Joined: March 8th, 2008, 12:58 pm
- Stroker Displacement: 4563cc
- Vehicle Year: 1992
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
- Location: Cyprus
- Contact:
Re: 4.2 mini-stroker spark plug temperature?
The reason is basically to reduce the risk of detonation now that you're running higher static & dynamic compression ratios.
Stock plugs are Champion RC12LYC so you could use the colder RC10LYC.
Stock plugs are Champion RC12LYC so you could use the colder RC10LYC.
1992 XJ 4.6 I6 - 5MT - Stroker build-up, Stroker "recipes" Sold
1995 Mustang GT - 4AT - Modded Sold
2006 Mustang GT - 5MT - Modded Midlife Crisis Car
1995 Mustang GT - 4AT - Modded Sold
2006 Mustang GT - 5MT - Modded Midlife Crisis Car
-
- Noob
- Posts: 15
- Joined: December 9th, 2017, 9:40 am
- Vehicle Year: 2001
- Vehicle Make: Jeep
- Vehicle Model: Cherokee
Re: 4.2 mini-stroker spark plug temperature?
Thanks guys. I ended up grabbing some NGK BKR7E-11's and gapped them to .035". Once I've done the initial engine break-in, I'll pull them and check for fouling to see if I need to go hotter.
Who is online
Users browsing this forum: No registered users and 6 guests