Spark plugs for 5.7 Hemi

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

Mister Luck

cassis tutissima virtus
Joined
Aug 25, 2020
Posts
1,543
Reaction score
516
Location
WEST COAST
Ram Year
2016/2017
Engine
5.7 V8
Iridium tipped spark plugs
are they OE from the factory?
I’ve heard horror stories for years about the tip dislodging and scoring the cylinder walls and that sales fumbled in Europe among the performance crowd.

I know with other improvements of other Chrysler based engines the spark plug is greatly over looked and one of the last parts to be upgraded/ changed probably from the perspective of profit margins and availability inventory on hand.

The compression ratio was again increased in the 5.7 around 2013

2009–20125.7 L (345 cu in) Hemi V8390 hp (291 kW; 395 PS)407 lb⋅ft (552 N⋅m)
2013–20185.7 L (345 cu in) Hemi V8395 hp (295 kW; 400 PS)410 lb

This should have prompted a study into heat range applications for the spark plugs but the same plugs are being used I believe as early as pre 2009.

Copper center electrode plugs themselves round off from cylinder temps and compression ratios vary depending upon the fuel or additives used.
Iridium and platinum plug tips are only as good as the material they are attached to.

The timing of the 5.7 is controlled by the air intake and in closed loop operation the O2 sensors , and if burning a lower octane fuel retarding the timing is noticeable under load or traveling on long grades.

Adjusting coolant temperatures settings and installing a lower threshold coolant temp sensor is also something to take into consideration when changing heat ranges of spark plugs.

Unless you have dynamometer printouts that are not over corrected for SI or Pa pressure you’re just measuring performance improvements by the seat of your pants.

 
Last edited:

GTyankee

Senior Member
Supporting Member
Military
Joined
Nov 2, 2020
Posts
10,063
Reaction score
12,607
Location
El Cajon Calif. 92021
Ram Year
2016
Engine
3.0 ecodiesel
Rockauto tells you what is OEM & what the current manufacturers recommendations are


Rockauto is also a vendor on this site

 

EdGs

Senior Member
Joined
Nov 29, 2020
Posts
2,478
Reaction score
3,556
Location
FL
Ram Year
2015
Engine
Hemi 5.7L
NGK 92145
Best price usually RockAuto
I also have a 2014 hemi, had these plugs in for 20K miles they look great.
^^^^ This^^^^
Should run you $6 and change each at RockAuto.

They should all be pre-gapped, so if you check them, be very careful as the electrodes are teeny-tiny.

Also, get the GearWrench 80546 magnetic swivel spark plug socket from Amazon. Should be about $15. You will be glad you did.
 

Johnny_B-Good

Senior Member
Joined
Aug 3, 2021
Posts
116
Reaction score
120
Location
Pennsylvania
Ram Year
2010
Engine
5.7 Hemi
I was in the same boat. Wanted to get new plugs in my 2010 Laramie before winter kicked in. Seen a lot of guys around here talking about the NGK Iridium. So that's what I went with. I'm thankful for all these guys around here who know so much about these trucks. Cause they help those of us who are learning every day...
 

Wulf

Senior Member
Military
Joined
May 16, 2021
Posts
182
Reaction score
77
Location
United States
Ram Year
2021
Engine
5.7 Hemi
Unless you have dynamometer printouts that are not over corrected for SI or Pa pressure you’re just measuring performance improvements by the seat of your pants.
Most of the time, that is the best dynamometer to use. I looked into the factory stats/specs on my new Warlock, and it said 0-60 (MPH) times were about 6.5 seconds. I independently confirmed this, sitting at a stop light, waited until it turned green, then stomped on the gas. Had to try it again as it spun the back tires, so into 4WD it went, and on the second/actual test, it did roughly that time. Put a new K&N air filter in it, no other changes, and got it down to about 6 seconds flat. All using that "seat of the pants" style dynamometer, less expensive to maintain, and usually a lot easier to calibrate.

The new Hurricane motors are allegedly comparable to the current V8 HEMI offerings, reportedly with better fuel economy, and better output numbers. The "standard" output (400HP/450FP), according to reported numbers, beats the current 345 ci (5.7l 395/410) with the "high" output (500/475) being compared to the 392 (6.4l 485/475). Guess time will tell how good they do, especially with the "savings" offset being eaten up by recommended high octane for the SO and required for the HO versions.
 

16MaxSteelOutdoorsman

Junior Member
Joined
Aug 31, 2016
Posts
18
Reaction score
13
Location
Aiken, SC
Ram Year
2016
Engine
Hemi 5.7
I just put in Autolite Double Platinum, that was all I could get, they were about $5 a piece. The NGK Iridiums were $13.99 ea and backordered. Wasn't a bad experience, I have a nice toolset so the different sized extensions and the swivel attachments worked well. Honestly, the rear three spark plugs on any front wheel drive V6 engine (Vulcan 3.0L, GM 3.1 and 3.8L) I have changed were far more challenging than the ones under the brake booster on the Ram.

90k mi and the truck runs like new. I didn't realize how degraded the power had become. That's the longest I've ever gone on a set of plugs.
 
Last edited:

Octane

Senior Member
Joined
Jun 8, 2019
Posts
1,526
Reaction score
2,073
Location
U S.A.
I just put in Automate Double Platinum, that was all I could get, they were about $5 a piece. The NGK Iridiums were $13.99 ea and backordered. Wasn't a bad experience, I have a nice toolset so the different sized extensions and the swivel attachments worked well. Honestly, the rear three spark plugs on any front wheel drive V6 engine (Vulcan 3.0L, GM 3.1 and 3.8L) I have changed were far more challenging than the ones under the brake booster on the Ram.

90k mi and the truck runs like new. I didn't realize how degraded the power had become. That's the longest I've ever gone on a set of plugs.
Plug replacement on Ram hemi not as bad,in my experience,as some others also. Some folks lack the skills and mindset I suppose.
 

T Ram 20

Junior Member
Joined
Feb 14, 2023
Posts
3
Reaction score
0
Location
USA
Ram Year
2020
Engine
5.7l
Hello I have a detonation problem pings when in 3rd or 4th gear under moderate acceleration I have replace the map sensor and has helped a little even replaced knock sensor and has helped a little i think its do to ram has never updated spark plugs through the years with the same heat range i know they have went up in compression and always kept the same heat range spark plug with a rather healthy projected tip only updating to Iridium spark plugs i believe that maybe a little less projected tip plug and one step colder spark plug should be the cure, what you guys thing about that
sorry my truck is a 2020 ram 1500 4x4 E torque 24000 miles
 

Latest posts

Forum statistics

Threads
194,925
Posts
2,864,167
Members
155,293
Latest member
RedFlameRam
Top