heh.. and THAT is also concensus! BTW, if you see Motorcraft filters on sale in size that fits Blazer. Go ahead, they are Purolator Plus. Not likely, though, Motorcraft is only stocked for Ford apps in most stores
Caveat: There's evidence NGK makes AC Delco Iridium. Dont automatically assume they also make the Plats.
Example: Autolites in 4.3 draw gripes even though Autolite MAY make some AC Delco std and plats. Wanna be sure.. buy the OE brand unless you have good reason to think the aftermarket brand works.

 

so in the AC plugs would you the platinum plus or the rapid fires on a high mileage 4.3 (132,000 mile)

why all the questions are memorial day weekend this old blazer is headed out on a 1000 mile round trip journey and would like to optimize it for the trip for best mileage and hwy power the old beast well be loaded down with about 1500 of people and their stuff.

 

Stant! Tstat and cap. Check all hoses for any sign of checking and soft softs. Fluid should be translucent. If muddy at all, flush.

Dont obsess over these plugs. Just ACD plats like CH said.
Hi-mileage?!! How much oil do you burn? That's all that matters in plug selection; less than a qt in 1500, then no effect. Unless you want to do a cylinder leakdown compression test.

 

stant make a theromstat (Pro) that has a v cut in to it supposed to be better temp control. I am not sure I am sold on their theory on it but think I will got the OEM style stant

oil consumption on the old blazer is about 1/2 quart in 2500 miles. so would you go with the AC rapid fire plugs????

 

Dang! didnt I just say quit obsessing? Use what came in the truck new. You dont use oil! Rapidfire sounds like a sales gimmick to sell to racers.

On the OTHER hand....

Years ago all tstats had a little bleeder hole in the plate. It didnt work well after a while because it might plug, plus it delayed warm up on real cold days.

So the hole went away and the heater nipple was depended on because most cars use constant heater flow. But the problem with ordinary tstats is they sometimes tend to 'hunt'. That means they see hotter fluid, open too far, then close back down. That makes people .. esp me.. nervous because that is also an indication of bubbles from combustion gases like a bad head gasket.

So stant realized a couple things, a little flow when closed was a good thing. Not only to keep accurate tabs on real coolant temp flowign past the pellet but to help purge trapped air/vapor. So how to make it 'self cleaning'? Answer... a little notch in the valve pintle will self-clean. If a chunk of anything lodges, it will go on through when tstat opens. And since it's self cleaning it can be even smaller than the old 'bypass hole'.
IF you have been paying attention the last couple months you might notice a LOT of us had problems with 'ratcheting' thermostats. All of a sudden MANY of them barely allowing engine to get to closed loop.

OEM's? Dunno, but seems suspicious.
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BTW, I just made up all that stuff that's italicized above, based on reading a little on the vstat blurb and what I know over 50 years. It's probably right but I dont know if stant would say exactly the same thing.

 

There is an O ring seal on the thermostat, that's it, no paper gasket, no RTV.

OEM calls for a 195F stat, I've never had a problem with Stant. The 195F means it begins to open at 195F and will usually regulate coolant temperature ~198F.

 

done some more highway driving today, thermostat is stuck open or it 150 degrees it was 80 degrees today and about 155 is about as hot as it got. so i definitely have a problem there so. I check the mileage over the last two days and averaged 16.4 mpg. so off to the parts store tomorrow and get a new 195 stant thermostat. if I remember right you all said if it don't get to 195 its never reaches closed loop so that were part of my mileage has gone.

 

On a cold engine, fuel vaporization is almost nonexistant, (fuel must be vaporized before it can be burned) so the fuel mixture needs to be richer. As the engine warms up the fuel vaporizes more easily and the fuel mixture can gradually be leaned out. On start up, if ambient temperature, ECT and IAT are all at 80F, the PCM should go into closed loop operation after approximately 3 to 4 minutes. With ECT at 155F, injector pulse width will be longer providing a richer mixture. When ECT reaches ~195 the fuel is vaporized very easily and the fuel mixture can be leaned out to 14.7:1 (ideal fuel mixture).

 

I seem to be a hard time finding a store around here that carry Stant Product especially thermostats (O'reily's and NAPA) having some family members check another near by town where they work and see if they have them over there. if not I might have to settle for a Murry from O'reily's

 

Murry/Four seasons is a good brand, they've been around for years. Not sure if they are an OEM supplier, but they have good stuff.