Spark Plugs on my Vic

[Colt45ws]

I decided to change my spark plugs today. Wasnt strictly necessary, but my tune is being setup for one step colder plugs. So I had to put them in before I can run it. Since Ive done this all that is left to do is wait for my tuner to email me the tune. Then I can pop my Marauder airbox/MAF in real quick and load it up. Ive already been filling with 92 for weeks in anticipation.

Went with Motorcraft SP500 or AGSF22FM in the old number system. These are one step colder Finewire Platinum. The originals are AGSF32PM. Most people go with AGSF22C which are copper. However, they also don't have the nickle plating that helps prevent the plugs seizing in the head. I opted against having to put plugs in it every 15k that could seize.




Spark Plugs #1-4 (L-R) They were wearing well and within tolerance. I think they wouldve made the whole 100k.


Spark Plugs #5-8 (L-R)


The new AGSF22FM. I used a 1/4" in-lb torque wrench set to 132in-lbs (11ft-lbs) to torque them in DRY.

 

[SteveSRT8]

nice looking set of plugs. That motor is tuned right and running well.

Whose throttle body is that?

 

[dwcopple]

Originally Posted By: SteveSRT8


Whose throttle body is that?
oem. but the plenum isn't...

 

[Fordiesel69]

Glad to hear for once someone did it correctly. Glad you didn;t use anti seize.........

Plugs looked great that you took out. I have to do my F-150 and they have 185k on them. The gap is 0.074 on one of them. You could probably do 125k at best on the original single platinums.

 

[Colt45ws]

Originally Posted By: dwcopple
Originally Posted By: SteveSRT8


Whose throttle body is that?
oem. but the plenum isn't...

Yup. Stock 65mm. My research shows the Trick Flow plenum still flows more with the factory TB than the original elbow ever thought of. I didnt think I'd need even more air through a larger one yet. When I get headers Ill probably acquire one of the 70mm units Ford put on some of the truck applications.

 

[Falcon_LS]

Colt, how does the car run on the stock tune with the SP-500 plugs?

 

[Colt45ws]

Perfectly fine. Smoother actually. I had the slight engine vibration in gear idle (550RPM). The TSB fix is a recalibration to set the idle to 600RPM. I never bothered since it was so slight I had to be looking for it.

 

[Falcon_LS]

I'm waiting to replace my plugs and upgrade to Steeda coils before I get my Marauder airbox and MAF on...was thinking about one range colder spark plugs, so thanks for the thumbs up!

BTW, why is the idle so low? Mine's set at 750 rpm, and the lowest I've seen it get is 748 rpm on the ScanGauge.

 

[Colt45ws]

Single exhaust cars were set like that for a few years. P/N idle is 650.

 

[Falcon_LS]

P/N is park/neutral?

 

[Colt45ws]

Yes.

 

[Vikas]

what do you mean "wasn't strictly necessary"? the tip seems to be completely eroded on old plugs as compared to the new

 

[SteveSRT8]

Those old plugs look terrific. In our fleet vans we routinely run high end NGK's to well over 200k miles and they still do not misfire.

 

[Colt45ws]

The old ones were regular platinum and the new ones are finewire platinum. Different design. Like Steve said the old ones are in great shape. I actually saved them in case I ever go back to stock. They will go back in.