NGK vs. AC/Delco
Thread Starter
Racer
Joined: Oct 2013
Posts: 466
Likes: 3
From: Carol Stream IL
St. Jude Donor '14
NGK vs. AC/Delco
So I decided to upgrade to what I thought would be an upgrade in spark plugs which were the NGK TR5 V-Power plugs from my stock LS3 AC/Delco plugs.
My car has minor boltons: CAI/Headers/Tune/etc...
I ran the AC/Delco plugs about a week and a half ago in 800 DA and saw 0 KR (Knock Ratio) with HP Tuners.
Fast forward to this past Sunday and me putting in the new NGK TR5 plugs. I made 0 changes to the tune, DA was 1900, meaning that the air was fatter and I shouldn't have seen any knock whatsoever. Wound up getting about 6.7 KR through 2nd and 3rd gear. I could only imagine how bad the knock would have been in lower DA.
Anyways,
I'm going to be switching back to AC/Delco plugs, but haven't decided on LS7 plugs or LS9 plugs. I'd like your input and thoughts.
Thanks,
Jason
My car has minor boltons: CAI/Headers/Tune/etc...
I ran the AC/Delco plugs about a week and a half ago in 800 DA and saw 0 KR (Knock Ratio) with HP Tuners.
Fast forward to this past Sunday and me putting in the new NGK TR5 plugs. I made 0 changes to the tune, DA was 1900, meaning that the air was fatter and I shouldn't have seen any knock whatsoever. Wound up getting about 6.7 KR through 2nd and 3rd gear. I could only imagine how bad the knock would have been in lower DA.
Anyways,
I'm going to be switching back to AC/Delco plugs, but haven't decided on LS7 plugs or LS9 plugs. I'd like your input and thoughts.
Thanks,
Jason
Safety Car
Joined: Jul 2009
Posts: 3,755
Likes: 190
From: Baton Rouge LA
St. Jude Donor '14, '16
Interesting, you did go 2 steps colder than stock with the tr5's so I wonder if that could be the reason (I honestly have no idea)..this is assuming you have an ls3.
I recently swapped from my delco plugs to tr6ix's on mine and got rid of the knock I was seeing in my scans. I can't add any timing but the stock timing table no longer knocks.
I recently swapped from my delco plugs to tr6ix's on mine and got rid of the knock I was seeing in my scans. I can't add any timing but the stock timing table no longer knocks.
Thread Starter
Racer
Joined: Oct 2013
Posts: 466
Likes: 3
From: Carol Stream IL
St. Jude Donor '14
Interesting, you did go 2 steps colder than stock with the tr5's so I wonder if that could be the reason (I honestly have no idea)..this is assuming you have an ls3.
I recently swapped from my delco plugs to tr6ix's on mine and got rid of the knock I was seeing in my scans. I can't add any timing but the stock timing table no longer knocks.
I recently swapped from my delco plugs to tr6ix's on mine and got rid of the knock I was seeing in my scans. I can't add any timing but the stock timing table no longer knocks.
Thread Starter
Racer
Joined: Oct 2013
Posts: 466
Likes: 3
From: Carol Stream IL
St. Jude Donor '14
I think you have that backwards Dennis. Lets say for example if I run 25 degrees of timing, if the DA is 1000 and I get 5 KR I know I need to take out timing or add fuel.
With that same 25 degrees of timing, if the DA is 0, KR will be much higher than 5 KR because of the denser colder air charge, making the car run more lean.
Intermediate
Joined: Dec 2013
Posts: 49
Likes: 3
From: Kansas City MO
I have had good luck with the E3 plugs in my Harley - Davidson. I do not have them in my 13 GS but would not hesitate to do so. I believe the part number is 3.54 for the LS3 engine. Probably the same for an LS2. I'm not going to change out my plugs yet since I only have 3k miles on the car, but would try the E3's when it is time.
Race Director
Joined: Mar 2005
Posts: 11,549
Likes: 27
From: Southampton NJ
Plug gap is the same 40 gap.
I think you have that backwards Dennis. Lets say for example if I run 25 degrees of timing, if the DA is 1000 and I get 5 KR I know I need to take out timing or add fuel.
With that same 25 degrees of timing, if the DA is 0, KR will be much higher than 5 KR because of the denser colder air charge, making the car run more lean.
I think you have that backwards Dennis. Lets say for example if I run 25 degrees of timing, if the DA is 1000 and I get 5 KR I know I need to take out timing or add fuel.
With that same 25 degrees of timing, if the DA is 0, KR will be much higher than 5 KR because of the denser colder air charge, making the car run more lean.
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