im replacing the plugs in my 235 . im not sure why . they are probably 15+ yrs old and still firing . anyway the ones in it are autolite 75 .orily said it should have 85 .im not sure of the difference or if either is correct . any insite . mtr. is a 62 .261 cam split ss headers , one barrel . very little hwy driving . thnx , bill
Depends on what "Autolite" are you talking about, or country of origin. QC is kind of hit and miss anymore for the old line trusted brand names as they offshore production to golly knows where. A lot of people seem to like NGK fwiw.
I agree completely, the last Autolites I saw were made in China. I also used to use Champion, they were my go to. Bad QC after leaving the US. Now, only NGK.
Post some pics of the "business end" of the plugs you removed. Close up if you can get them in focus.
so these are the correct, and best plugs for my ap . the price is nice . but you have to purchase 8 from rock and $10 shipping . not that price matters if they are better .
Most of the plug companies cut down on the number of offerings in spark plugs in the last few years. An Autolite 85 is a frog hair hotter than an Autolite 75 but I wouldn't get too excited over it with your driving. Rock auto shows a number of plug offerings for a 62 Biscayne 235 depending on how fancy you want to get in plug choice. 1962 CHEVROLET BISCAYNE 3.8L 235cid L6 Spark Plug | RockAuto All are available at local parts houses though.
Depends how picky you are, and how sharp a tune you got going. Stock point style ignition & coil, the OEM probably used a heat range that would tend to keep fouling down especially in city driving. If you've upgraded the ignition, and the carburetor is actually calibrated, a skosh cooler plug might work better. It's kind of tricky with modern gasoline, all those plug color charts are kind of useless. The idea is to have the spark plug heat range just hot enough to keep fouling from accumulating.
well my tuning could be called a lot of things . but sharp probably wouldnt be in there anywhere! i bought and installed a hei dist but i was un -impressed with the fit , or the chinese build quality so i went back to the 60 year old stock dist. fits much better . and they are so simple there is not much that can fail or even wear out .finding quality points is the main pain . thank you mao satong !! the main reason im even changing plugs is that 3 of the gasket on the old ones have disapeared along there travels . i also opened up the gap for the hei . then closed it back down after the return to points .i dont know how many times you can bend them before failure . and really dont want to find out . but they still fire fine .and no fouling ever . so i guess ill install the ones i have and see how they work . a new set of wires should probably be in my future as well . i cant remember where they came from . but i know they werent new . these stovebolts are pretty easy to work on and seam to want to run ,no matter if a few cylinders are 100 percent . its just sad they are so f%#c*%g heavy . probably no light weight alu. blocks or heads coming any time soon . so i guess you just have to make the best of what it is !!
Just a good basic spark plug - no fine wire platinum or anything is necessary or even wanted. I would not bend a ground electrode more than once, it doesn't take much for them to break off. A lot of carburetors are setup to "pig rich under any/all condition" specification, with defective fuel pump, power circuit, and float level added in there to make damn sure the plugs foul badly in just a few seconds.
well i installed the autolite 85 . since i already had them .we will see . limited mi . and seem fine . as long as the head dosnt fail , again . im sure they will be fine .i will pull one soon to see what it looks like . now that ive got some heat to the intake , im expecting them to be fine . mtr still starts up after about 1/2 revolutions hot or cold . no choke when its 30 degrees . no smoke . idles grt . i dont understand why . but i guess it could be worse ! i do see a lot of condensation on cold start for several minutes . i guess that is normal . but still seems a bit excessive . im not sure what it could hurt aside from rotting the exhaust out !
i know what your saying . but runs grt. , no smoke . im very happy with the power . .only thing is very poor milage !
If the carb and choke are working properly and the rest of your tune-up is OK, the choke should set for a cold start and temporarily make the make the mixture richer. This promotes easier cold starting and quicker engine warm up. Cold engines need a richer fuel mixture. As the engine warms up the choke should come off and the fuel mixture should lean out to where it needs to be at normal operating temperatures and provide better gas mileage. If for some reason the carb is normally running rich without setting the choke it will tend to start OK when cold. But as the engine warms up it continues to run richer than necessary and kills your mileage. And it can also lead to spark plug fouling, excessive blow-by and oil dilution.
I've got a 261 in my 62 impala with a 3spd stick and I think I'll go with AC45s if I can get them. NGK is also a good plug. Lippy
Post a clear closeup pic of an old plug or two so we can see the "color". There is not going to be a power benefit to just simply wasting fuel, you won't lose a thing by a good tune-up.
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