Spark Plugs for LS Motor

Bobalos

Bobalos

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Does anyone have a flavor preference for plugs for an LS motor (380 HP TurnKey crate engine)?  IIRC my motor has Denso 4511 PT16TT Platinum plugs in it. 

I have always put AC Delco's into my GM's, but dont have a good reason for it other than this is what Ive always done. 

thoughts?

Bob

 
Kraut_n_Rice said:
NGK TR6IX,  #3689
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that is a good plug, 

also for a sand car that has less use, and more affordable, is a TR-5 but the TR-5 has a removable end for different style plugs so a good affordable plug i use is a TR-55  that would be good for up to 10.5 compression midrange RPM, Midrange cam,  TR-6 and TR-6IX will be good for in town driving real pump fuel, and more aggressive Cam,  and Boosted i would go to a TR-7 

 
I am a fan of the NGK TR plugs as well

I spent Time talking with Jim Bell about these plug vs Iridiums and he schooled me and has the Dyno results to prove it 

The are good BUT you need to understand what the numbers mean  

NUMBERS ARE IMPORTANT

TRx  where x is the heat range    The higher the number the colder the plug

The Standard LS engine LS1, 2, 3 and 5.3 are all in the 10-10.5:1 compression range and with a mild to medium cam  they should use the standard TR 5 heat range

If you have a bigger cam and throw more timing into the engine then the TR55 is a good choice its slightly colder  and can tolerate more timing, but will foul up pretyty quickly in stock engine especially if the engine runs under 200 degrees water temp

The TR6 is my goto for SC and Turbo cars  it cold  .... and safe

Don't run a TR55 or TR6 in a stock or mild cam engine  - you will be giving up a lot of TQ and HP

GAP is IMPORTANT

If you run pump gas you can gap the plugs to  040  this will give you the best flame travel and is not hard on the coils - some people go to 055 but the coils run hot especially on a MEFI or Holley or other aftermarket ECMs.  If you have D585 Coils  you can tune up to .045 gap. (ls Truck  coils)  the Popular LS1 coils  D581 will not handle over .040 nor will other OE coils.  The MSD and Accels are worse than any factory coil  in every test I have seen (except the manufacturers tests of course  🙂

If you run and SC or Turbo under 20Lbs boost a 035 gap is ideal  - over 20lbs go down to 25 or you will blow the spark out when boost comes up

You should never have to go to a TR7 on a boosted car - you are giving up way too much HP - the flame travel suffers - you should fix the timing or the cam profile - or maybe you have 40Lbs of boost on M1 or 116 (doubtful)  I reserve those plugs for Nitrous cars with 1000HP shot and know they are gonna melt the plugs constantly anyway.

ALL TR series plugs come out of the box at .035 assuming they did not get bounced around 

I always use "boot dresing on the plugs as well "dielectric grease"  it ensures there is no corrosion. 

I always check the resistance of the wires on plug change or just change them - Wires wear out and new plugs will exaggerate and issues with the wires 

 
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I dont agree, on the Tr-7 comment, Talking to DuneHoon, calling NGK hotline and talking to other tuners, going with 11;1 and 16-21lbs of boost, the Tr-7 is our goto, at the end of the day the piston quality and longevity is our main concern, 

 
J Alper said:
NGK.com: NGK Technical Support

great guys,  you can send them our plugs also, they are super helpful 

NGK.com: TR55 $4.22 NGK 3951 Spark Plug - Best Car Spark Plug Replacement

The TR-5 and TR-55 is the same head range, you can call NGK to verify, the only difference is the end of the TR5 comes off for some European cars and the gap on the Tr-5 is .039 and the gap on the Tr-55 is .059  
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True and false - a 1/2 step is not nuch .... if you believe every $8 an hour support guy  - you will be in trouble -  the TR55 is a "reduced cost" version of the TR5  made for OEM  - it has a different "angle" on the porcelain  - cut them apart  and see - they are a 1/2 step colder  - but in reality 1/2 step is not that much  on a "STOCK STREET CAR"  but for my car sand I want the best I can get  - I pay $3.19 at O-reilly here in the LA so bay for the TR5's  so even though the TR55's are cost reduced I guess they are not as popular and cost more??? I never priced them 

 
thanks for the input folks, I appreciate it. all I know for certain is that this is a TK engine that I run Pump gas in.  LOL.  Actually TK was able to confirm more about the motor.  uber cool that they keep those kinds of records. 

is this right??  if so, then mine is the D585 Coil. 

D581 CD581 GM Coil.jpg

D585 Coil:

D585 GM Coil.jpeg

 
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I did not have the original so I took a pic from my notes - this all the Ls coils

This is from Holley on line - they have SO much great info  - Most people don't bother to read it,  but its all there 

LS coils.jpeg

 
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Bobalos said:
thanks for the input folks, I appreciate it. all I know for certain is that this is a TK engine that I run Pump gas in.  LOL.  Actually TK was able to confirm more about the motor.  uber cool that they keep those kinds of records. 

is this right??  if so, then mine is the D585 Coil. 

TK is great from that perspective Kolby knows every part number in your engine. 

Depending on the ECM you have, you can play with setting on the coils and get maximum spark at all RPMs 

But the 585's are King 
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@Fullthrottleguy,

Sorry I dont want to beat this to death, I just got online & found different things & just want to get this done.  this has been quite enlightening about the coils & fuels & such. 

it looks like there is an iridium TR5 (NGK 1465 IZTR5B11 Laser Iridium Spark Plug) and a "normal" TR5 (NGK 2238 TR5 V-Power Spark Plug).  I would assume you are suggesting the 2238 std V-Power plug & not the iridium plug?

FWIW, its a MEFI with pump gas.  TK said its a "390HP/410FtLbs, basic LS with GM heads".

While we are on the topic of ignition parts. are all wires created equal?  I know some years ago the "Fire Core" brand was all the rage.  I dont want any kind of "trick of the day" stuff, just good reliable parts.  Delco? Accell? SplitFire? 

thanks

Bob

 
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Everyone has there preference, but for me I only use Taylor 409 Wires, they have been flawless for me, 

The MSD wires always give me issues wit the gray boots falling apart around the spark plug wire,

 
Bobalos said:
@Fullthrottleguy,

Sorry I dont want to beat this to death, I just got online & found different things & just want to get this done.  this has been quite enlightening about the coils & fuels & such. 

it looks like there is an iridium TR5 (NGK 1465 IZTR5B11 Laser Iridium Spark Plug) and a "normal" TR5 (NGK 2238 TR5 V-Power Spark Plug).  I would assume you are suggesting the 2238 std V-Power plug & not the iridium plug?

FWIW, its a MEFI with pump gas.  TK said its a "390HP/410FtLbs, basic LS with GM heads".

While we are on the topic of ignition parts. are all wires created equal?  I know some years ago the "Fire Core" brand was all the rage.  I dont want any kind of "trick of the day" stuff, just good reliable parts.  Delco? Accell? SplitFire? 

thanks

Bob
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I dd not want to beat it to death either ... But its funny I was talking to a buddy at Powermedia last night about a set of heads he has, and he saw this thread and told me I was a little off on the TR5 vs TR55 .. He said the TR55 is the OEM version and the reason the Porcelain is different is because its made for a Wider 055-060 gap but I was correct saying its a colder plug - he said you should not gap a TR55 to 035  the electrode strap will not be parallel.  He also told me to always use the Allstar style plug gapper to keep the electrode flat on all plugs ... so I ordered one. 

And yes STD plug Not iridum -

I am really familiar with the TK 390/410  the 390 is the 5.3L version and 410 is 5.7L version (usually using a bored l33 5.7 Block)  Its basically a stock LS but with headers, K&N  and a tune   799. 241. 0r 243 heads and better spring

Wires... I have tried them all - everyone has a preference- for me I am normally always good with Delco, I tried Nology, Taylor, Accel  etc. but I use MSD personally have had them on the last 3 cars no issues and I change plugs 3x a year and read them every trip so lots of pulling boots  just use grease .

I also use these spark plg wire sleeves on every car https://www.amazon.com/Degree-Shield-Protector-Sleeve-Shinehome/dp/B0196D53NU/ref=sr_1_3?crid=38F3DG8QM07JA&keywords=spark+plug+wire+sleeves&qid=1646951603&sprefix=spark+plug+wire+sleeves%2Caps%2C138&sr=8-3

any brand is usually good since heat kills wires and boots, this just saves them from getting dried out and cracked  - the grease even stay flexible so you don't rip a boot.   I do use a boot tool to remove boots as a best practice so you don't stretch the plug wire   - thats important since the core is Not wire  and stretching it will ruin it

Screen Shot 2022-03-10 at 2.33.57 PM.png

Coils - can't beat Factory

Screen Shot 2022-03-10 at 2.38.26 PM.png

 
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I also feel the AC Delco Coils are amazing,  I have purchased some on Ebay and Amazon to see, and they are fake,  the ones on my Chevy truck say ACDelco on the coil and have a symbol.

This is a good wire remover also, 

Leslie, puller from summit, 

LIL-51250_xl (1).jpg

 
The wire sleeves are not "a one size fits all" kinda deal.  I have Taylor wires.  They seem considerably better than the Johnson(?) ones I had before.  BUT, the boots are pretty big, and I couldn't get the sleeves over them with out re"engineering" them..

 
Kraut_n_Rice said:
The wire sleeves are not "a one size fits all" kinda deal.  I have Taylor wires.  They seem considerably better than the Johnson(?) ones I had before.  BUT, the boots are pretty big, and I couldn't get the sleeves over them with out re"engineering" them..
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Thats probably true... Something to consider ... I  never used them with anything But MSD wires, But I did have to remove the "hog ring" to get them over my MSD wires and then put it back on  - but they don't fall off which is nice. The nice thing about the Delco's is you don't need them - just used the nice Metal sleeves - 

I am sure if you buy them from bay or maybe Amazon they will be knock off like everything else :-(

Screen Shot 2022-03-10 at 8.11.09 PM.png

 
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Just so my Honda peeps don't think I'm cheating on them..;p

All of this is in my 402 LS2 street ride...higher compression, big cam, long tube headers....

The theory in these last couple threads is not to be dismissed. Heat range vs timing and compression.  Platforms seem to have minimal differences.




 
Fullthrottleguy said:
Thats probably true... Something to consider ... I  never used them with anything But MSD wires, But I did have to remove the "hog ring" to get them over my MSD wires and then put it back on  - but they don't fall off which is nice. The nice thing about the Delco's is you don't need them - just used the nice Metal sleeves - 

I am sure if you buy them from bay or maybe Amazon they will be knock off like everything else :-(

View attachment 27832
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right............. so where do you go to get the real parts????

 
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