Droops83

WR7DC gapped to .028"

Amber Gramps

I'm guessing .7mm or .8mm is equal to .028". thanks guys. Looks like plugs, oil, and the dreaded valves are going to be my saturday fun in the sun.

shipard

Sorry to come in late, and excuse the ignorance.....but what is so bad about platinum spark plugs ?

KC911

LOTS of us run those NGKs and they're great plugs and available almost everywhere at reasonable prices. Shipard, there's nothing wrong with platinum plugs per se, it just seems from everyone's "real world" experiences over the years that copper plugs produce better results for "these" cars...NGK or Bosch...both are fine.

Keith
'88 CE coupe

J. Brinkley

for general info if you ask a counter guy for a wr7dc he gets kinda lost, at least in the stores around here.
The number on a box of ten for the wr7 is 7501, which is something they understand.
The smaller the number in a bosch plug the colder it is.
The smaller the number in a NKG plug the hotter it is.
Wr7DC bosch number is 7592
Wr6DC bosch number is 7595
Wr5DC bosch number is 7592
any of these, or the champion, NGK, or denso are less than 2$ online.

Peter Zimmermann

douglas: I know that you didn't ask, and I don't want to offend, but please make sure that, if you're going to adjust your valves, that you do them before you remove the spark plugs. This is really important, and it will make the engine a little harder to manually turn from one cylinder to the next, but it's the only way that you can prevent carbon/debris from interfering with an exhaust valve(s) closing properly. And yes, inch = mm x .03937 (.7mm x .03937 = .028")

Amber Gramps

Pete, thank you so much for this. Some times I have questions that I don't get out. Like "should I pull the plugs out, then do the valves, then put the plugs back?" or "Should I do the plugs, make sure they are all working, then do the valves, or the other way around". How much do I owe you now?
I wouldn't have done the first question for fear of dropping something in the sparkplug hole....But still had to ask. I still want to treat them as two totally differant jobs with a good run between so if something is wrong I don't have to look at both jobs. Are there any tips for doing the valves or getting the engine ready to do the valves like cleaning or blowing off dirt?

Peter Zimmermann

Have 3 or 4 aerosol cans of brake/parts cleaner on hand, as well as lacquer thinner. I like the blue, throw-away shop towels (in a roll like paper towels) sold in many places, and always have a roll handy. Cleaning is easier after the covers are off - I always count nuts and washers during removal to be sure that nothing can find its way into the engine. Sometimes the old cover gaskets will break apart during removal, I lay out the pieces on a shop towel to make sure that I got it all, then straight into the trash with it. Most aerosol cleaner is not compatible with paint, so have a degreaser that you can use on the painted troughs below the upper covers. The easiest way to clean the covers is to brush them with lacquer thinner, wipe them with a shop towel, then final clean them with aerosol parts cleaner. You really can't goof up plug replacement, gap them properly and replace them after you're done with the valve adjustment, but before you put the upper covers back on. A thin smear of lithium-based moly grease, applied with a brush or fingertip, is all that you need on the threads (see pic below) - if the last shop used anti-seize you might find that the old ones are difficult to remove (this becomes much easier if you do it with the covers off). Get the gasket surfaces on the covers and cam housings nice and clean, I use single-edged razor blades on the nasty stuff. Try to get the covers off without using a wedge (like a screwdriver) between the cover and housing, try a soft mallet, etc., before resorting to heavy duty tactics!

theiceman

hey Pete new covers go on dry ? anuy opinions on leaks where the nuts are ?

Peter Zimmermann

ice: Yes, they go on dry. The seepage at the nuts is not seen often, but it's usually caused by cheap hardware or under-torqued nuts. Avoid the cheap hardware by using a Wrightwood Racing kit if possible (you will get the good washers with that kit). Use 18 lb/ft torque for the other problem; tighten starting at bottom center and work outwards, and up and down. I generally make the nuts nice and snug, then go back and torque them. Just make sure that everything is clean, both gasket surfaces and the surfaces where the sealing washers fit against. If necessary a little touch up here and there with a flat file doesn't hurt.

LUCKe27

Wow. It's posts like this that make it clear that I'll be paying some mechanic around here quite a bit of money. No way I could do all that without on site instruction.

der Mond

My '87 ran most excellently and got over 26 mpg at 90 mph average with NGK Iridium plugs, which I used for the 30K miles I drove the car. Nippondenso makes ones that require even less juice to fire. They last a long time and deliver. I use them in every application I can including my snowmachine, a Ski-Doo Skandic Sport 500 fan, which pull-starts at -40F with them, gapped large. My new Honda Fit has Iridium plugs standard, and there is a reason for that. They cost more. The really costly part is years of psychotherapy for Obsessive-Compulsive Disorder! Good thing I sold that car! I'll shut up and go away now...

Amber Gramps

der Mond, how the heck are you? We miss you and your ven blu met. The stock spec Bosch go in tonight after the valve covers go back on. You know what happens when you let Pete Z. in on the decision....everything bone stock. Keep warm and keep up the OCD, it's good for you.

Peter Zimmermann

Dennis: That's not necessarily a dissenting view, just an intelligent observation based on personal experience! I also liked NGKs, but found that they were only better than comparable Bosch plugs in earlier 911s fitted with either carbs or MFI. NGKs actually transformed some MFI cars, that we maintained, from ho-hum to wow, but in CIS cars, especially, absolutely nothing that we tried worked as well as good old copper core Bosch plugs.

der Mond

..and that's why I shouldn't try this at home =) Good to hear from you, Pete!