IHADAV8.com - Turbo Buick Tech, and Nonsense

Tech Area => General Buick Tech => Topic started by: Scoobum on July 11 2016, 08:02:19 PM

Title: Spark Plug Ground Electrode Gone
Post by: Scoobum on July 11 2016, 08:02:19 PM

What would cause a ground electrode on a spark plug on one of these engines to break off? Got a pic from a TR owner...and it's gone. He raced me earlier this year...and the car backfired horribly. BLM's were 142 after the run.


Forgot to mention after it backfired I found it had blown the PCV valve hose off. BLMs remained at 142 after reattaching it. He's sending me the PL file tomorrow. He says the boost spiked to 31.

Title: Re: Spark Plug Ground Electrode Gone
Post by: TexasT on July 11 2016, 10:01:10 PM

Detonation is a nasty force and if he was sportin 31psi I would guess that engine experienced some.

Title: Re: Spark Plug Ground Electrode Gone
Post by: Steve Wood on July 11 2016, 11:57:06 PM

Detonation and the resultant high cost combustion took it right off

Title: Re: Spark Plug Ground Electrode Gone
Post by: Forzfed on July 12 2016, 02:01:40 PM

I remember when I was injecting 20% Nitro and even though I ran C16 in the tank and it showed no knock on DS.  It still almost blew the tips off the spark plugs.

Title: Spark Plug Ground Electrode Gone
Post by: larrym on July 12 2016, 02:35:21 PM

Would a nonprojected tip help?

Title: Re: Spark Plug Ground Electrode Gone
Post by: Scoobum on July 12 2016, 03:28:48 PM

I haven't had any problems with spark plugs to date...with either alky or C 16...using 43's gapped at .030.

Title: Re: Spark Plug Ground Electrode Gone
Post by: gusszgs on July 13 2016, 11:04:39 AM

UR-5's here gapped @ .030 no issues alky only

Title: Re: Spark Plug Ground Electrode Gone
Post by: larrym on July 13 2016, 12:49:27 PM

I have run both UR5s and YR5s the only difference is the YR5s are non-projected tips.


I have read that the non-projected tip can help with pre-ignition they are popular with the boosted import crowd.

Title: Re: Spark Plug Ground Electrode Gone
Post by: Shimy87 on July 15 2016, 10:07:27 AM

I'm using 42's, should I be using 43's with my set up?

Title: Re: Spark Plug Ground Electrode Gone
Post by: Scoobum on July 15 2016, 11:02:31 AM

42's are for a higher boost level. You'd likely be better off with 43's. I run CR43TS...but that's just me.

Title: Re: Spark Plug Ground Electrode Gone
Post by: Steve Wood on July 15 2016, 11:13:22 AM

as usual, I agree with Brad.

I have to laugh when I see plug and plug gap suggestions today.  It seems that plug gaps keep getting tighter.  I have always run 0.035" for 25 psi or less and have accidentally logged 30 psi once when the hoses blew off the vacuum block without a hint of detonation.  Typically, I suggest 0.032" for boosts above 25 psi for no reason other than lots of people feel more comfortable with it.

The other day, on FB, some guy was having backfiring at 10 psi and mentioned he was gapping plugs at 0.032".  Promptly, some guy informed him that you cannot run boost on wide plug gaps like that.  He instructed him to set the gaps to 0.24" as I recall.  Several people promptly agreed with him.

I have seen several guys post that UR-5s/UR-6's are far too hot for boosted cars and others concur.

I am beginning to think we have been invaded by wannabes from a different time line.

Title: Re: Spark Plug Ground Electrode Gone
Post by: Shimy87 on July 15 2016, 12:09:52 PM

looks like I'll get some 43's and gap em at .035....thanks again fellas :cheers: