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Hi guys, i have looked but cant find the thread that has the cooler spark plug model number and gap measurements for modifyed cars.
Perhaps someone could point me in the right direction.
Hi guys, i have looked but cant find the thread that has the cooler spark plug model number and gap measurements for modifyed cars.
Perhaps someone could point me in the right direction.
Cheers
Timbo
You want NGK Laser Iridium Spark Plugs # ILKAR8H6-96024...Heat Range 8, gapped at around .036. OEM are HR 7.
"cooler spark plug model number and gap measurements for modifyed cars."
I would assume this to be referring to tuned cars from the OP question? But agree, not needed for stock (or even slightly modded) cars. A general rule of thumb, is one heat range colder than the OEM plugs for every ~ 75-100 horsepower added.
Yes..This is for V8. The V6 info is below. Appears the V6 plug is also the same OEM Heat Range (7C)...And same general rule on adding cooler plug would apply as well, based on increase HP, and Gap based on increased boost/pressures. Always best to check with your specific tuner on plug and gap recommendations. The info for the V8 I listed above is in line with what is recommended by VAP for their tune.
I was just checking through my manual and my 2016 uses ILKR6C10 plugs. Jaguar started using NGK ILKR7C10 plugs at some point. If I'm tuning and putting the pulley on am I okay with the 7C10 plugs? I'm hesitant to use the 8H6 plugs, the center electrode is projected while the OEM ones are not.
I'm no expert on this at all, but from the bit of reading I did a projected plug might not be recommended. People seem to recommend against them in boosted applications. I also read that the electrode in the combustion chamber may lead to pre-ignition, the thinking being the hot electrode tip of the plug may ignite the fuel on it's own before spark.
I was just checking through my manual and my 2016 uses ILKR6C10 plugs. Jaguar started using NGK ILKR7C10 plugs at some point. If I'm tuning and putting the pulley on am I okay with the 7C10 plugs? I'm hesitant to use the 8H6 plugs, the center electrode is projected while the OEM ones are not.
I'm no expert on this at all, but from the bit of reading I did a projected plug might not be recommended. People seem to recommend against them in boosted applications. I also read that the electrode in the combustion chamber may lead to pre-ignition, the thinking being the hot electrode tip of the plug may ignite the fuel on it's own before spark.
I may be overthinking this but what do you think?
Originally Posted by bcbruno
If i may ask, is ok vap tune (no pulleys) on standard 2015 R plugs or best change too?
VAP has changed their position on plugs, and NGK has apparently changed the pattern on their HR8 plugs. So now appears staying with the HR7 is preferred.
Appears Jaguar was initially using HR6 and switched OEM to HR7, so they are already 1 range cooler than original OEM plugs used early on.
Makes me wonder if pulling timing on a really hot day on the track with stock 380 tune might be solved with plugs. I always assumed it was heat soak due to inadequate intercooling. It doesn't do that unless you go WOT for lengthy time in 110F+ Do you think it might be factory plugs?
Makes me wonder if pulling timing on a really hot day on the track with stock 380 tune might be solved with plugs. I always assumed it was heat soak due to inadequate intercooling. It doesn't do that unless you go WOT for lengthy time in 110F+ Do you think it might be factory plugs?
I am no expert...But that is certainly possible, and easy and cheap enough to check out. Plugs are fairly cheap, and install is not bad. Worth trying. I also added Methanol/Water injection, so that should keep mine from pulling timing or pre-detonation with the cooler IAT and Octane boosted...But I would focus more on my plugs if I did not have that effect. You may be on to something...Give it a try!
I had the HR 8 plugs fitted and top end it misses like a bitch, so now i suppose im going to have to go back to std.
Am i right in saying 7C10 are the std plugs for the v8.
I had the HR 8 plugs fitted and top end it misses like a bitch, so now i suppose im going to have to go back to std.
Am i right in saying 7C10 are the std plugs for the v8.
That seems to be the consensus. Im going to gap them to .032 because I'm about to be tuned.
I had the HR 8 plugs fitted and top end it misses like a bitch, so now i suppose im going to have to go back to std.
Am i right in saying 7C10 are the std plugs for the v8.
Originally Posted by TM1238
That seems to be the consensus. Im going to gap them to .032 because I'm about to be tuned.
Yes...That is correct - NGK (94940) ILKAR7C10 Laser Iridium Spark Plug - That is the correct one. Recommended to be gapped .028-032. I went with .030 and will install before my 1/2 mile No-Fly-Zone race next month. 👍
DC
Last edited by Therock88; Apr 16, 2021 at 07:00 AM.
Makes me wonder if pulling timing on a really hot day on the track with stock 380 tune might be solved with plugs. I always assumed it was heat soak due to inadequate intercooling. It doesn't do that unless you go WOT for lengthy time in 110F+ Do you think it might be factory plugs?
My recommendation is don't assume, rather measure.
Data log ambient air temperature, IAT pre and post intercooler, ignition timing and throttle position.
110°F (43°C) is going to give any standard intercooler a hard time under track conditions. If an intercooler is extremely well designed and sized it would be impressive if it can get inlet air temperature down as low as + 10°C above ambient air temperature which in the example you cited would be 127°F ( 53°C ), and in most cases standard intercooling isn't going to anywhere near this level of cooling.
Cooler spark plug
