78 replies to this topic

[dodgetime]

huh?   well the long stroke of the 440 causes the electrodes to go into a hyperpsychloidal fibulations, due to this phenom it was beneficial to set the gaps at a mean value of the perogial/apogieal synusoidal swings squared, also aligning all electrode angles with the constelation Orion nets up to an additional -.2.  goodmorning   

[Pat McCrotch]

Is there a switch on here somewhere for English Morning to ya too.

[Speedy]

Gotta ask if there is any proven benefit with any type of indexing as in enhancing flame front ? I do know a 440-6PAK I once had the reigns of would without question run measurably better (hundredths) (no dyno runs) with the gap a few degrees towards the exhaust vs a random 8 plug change. No boost, 1 non centered plug, low power in comparison to some of these things but still my grey matter is a wondering about their orientation and effect if any ?             

 

This is a good question Geoff and something I've wondered about myself.

[StevoHemi]

Here is a clip that explains indexing. Too bad he used dirty heads. Would be able to see better with a new head.

 

 

Here is one on how to do it when you can't see the plug. Skip to... 2:00

 

 

This racer swears by indexing.

 

 

Aj, Andy, Mike OST what say you?

 

Stevo

[StevoHemi]

Good article on Spark Plug info from NGK.

 

http://www.ngksparkp....cfm#spinstall4

 

Stevo

[CaptRon]

Here is some info I obtained today regarding spark plugs.

We have a ton of customers who use 1 step colder plugs on their srt8's for use with strokers or Superchargers or basically any combination that nets them around 500rwhp. The plug most often used is listed below.
NGK-LZTR6AIX-13- Stock number 2315- 1 step colder for 6.1
Projected tip, Iridium

Now that we have been porting 6.4L heads left and right, I have a ton of 6.4L spark plugs in a box and I wanted to determine how they compared. Here is that part number.
NGK-LZTR6AP-11EG

The 6.4L plug is the same heat range as the 2315 plug listed above which makes it a good plug for 500rwhp applications. The differences are that the 6.4L plug is platinum and not iridium, it comes gapped at .044" instead of .052" like the 2315 plug above and it has a 10k ohm resistor instead of a 5k ohm resistor. Evidently 5k is industry standard but 10k is supposed to increase plug life.

Anyhow, just wanted to let everyone know that there is a new option available for a 1-step colder srt8 plug for 500rwhp applications. This will not work with the Eagle cylinder head as it has a washered seat plug and not a tapered seat plug like the 6.1 and 6.4.



For Eagle Heads
Stock Eagle Plug: NGK SPLZFR5C11
1 Step Colder: NGK ILZFR6D11 (Stock #1208) or NGK LFR6AIX-11 (Stock #6619)
1.5 Step Colder: Brisk ER14YS
2 Steps Colder: NGK LFR7AIX (Stock #2309)

So where is the best source for the NGK SPLZFR5C11 (stock plug)?

Autozone don't seem to stock them but Oreilly has them for 4.49.

[lakersfan7272]

Just swapped in some NGK 6510s, gapped to .028. Running eagle heads at 18psi and will be spraying 100-200 shot.

[Andy@PWR]

6510 are tapered seat pkugs john. You should be using washered plugs

[toofart]

I'm going to ask a dumb question:  why are folks changing the plugs so soon?  At 16 plugs it ain't cheap...

[Speedy]

I've only changed mine once and went to NGK 6619s in my Eagle heads.  One step colder and gasket seat.

[toofart]

Bump for spring...  I'm still bouncing between the 7787 (copper) or 6619.  

[ironchallenger]

6510'S ARE ON BACKORDER EVERYWHERE. 

 

 

fucking sucks. 

[BuckeyeGuy]

Got a used set I will sell you

[srt5939]

I know who has them 

[1FST4DR]

6510'S ARE ON BACKORDER EVERYWHERE. 

 

 

fucking sucks. 

 

 

How many sets you want?   I have 2315s and 6510s on the shelf at all times... I also carry brisk as well but now that the new vettes use the same plugs as us the local GM performance shops have been buying them up...  Might be why there is a shortage of 6510s..

[Speedy]

Bump for spring...  I'm still bouncing between the 7787 (copper) or 6619.  

 

I'd go for the 6619s.  They worked well for me.  I just went to a NGK 2309 (2 step colder) based on Mike @ OST reading my plugs.

[SRTROB]

Are the 6509s ok to use in place of the 2315s ? Brent told me to use 6509s as they are the same as 2315s except the ground strap is much shorter so you don't have to bend it way down like on the 2315 plug ?

[Yellow Jacket]

I have a full set of brand-new 2315's I just got from RockAuto before I read this thread! I'll be sending them back this week, or I can send them to whoever wants them. $115 for the set, which includes shipping.

[toofart]

I'd go for the 6619s.  They worked well for me.

 

Yep, I just pulled the trigger.