Hello all, quick question. I purchased some spark plugs at the local store and they gave me Champion RV17YC, which is what their computer reccomended. However when I got home and checked the emissions sticker on the truck it stated Champion RBL16Y. Can I use the RV17YC's on this or do I need to get the right plug? They look to be identical in size.(1983 Dodge Ram Slant 6, converted from Lean Burn to Electronic Ignition.
Thanks for your help
Nick
Remove number one when replying by electronic mail
WRONGO, that plug is too hot and will exacerbate this engine's already high tendency to ping.
Champion has gone consolidation-crazy over the last five to eight years, deleting plugs from their line left and right. This isn't because there's been some magical development in spark plugs that widens the heat range. It's because it's cheaper to have fewer plugs in a line than it is to have more plugs in a line. This is what happens when MBAs, rather than engineers, run auto parts companies.
Even these are unnecessarily hot on today's gasolines, which are much easier on spark plugs from a fouling perspective than were the gasolines of 22 years ago. You can go a range or even two ranges cooler and get some relief from pinging (which in turn can allow the disconnection of EGR and/or advancement of the ignition timing for improved driveability and mileage) without fear of pinging on today's cleaner-burning gasolines.
All my annotated spark plug books are at the office; tomorrow I'll dig up my notes on plugs for '75-'87 slant-6s with the taper-seat spark plugs. There are a few specific ones that work better than others, regardless of brand selection. I do not recommend you use the RV17YCs. (Yes, they are physically identical. No, that does not mean they're the same.)
FWIW, I believe that the primary way the heat range is tweaked on a plug design is in the amount of depth of the recess between thread body and insulator, effectively shortening or lengthening the heat path from the plug's tip to the cylinder head (big freaking heat sink). Since this detail is virtualy invisible to the casual observer, otherwise identical plugs by the same manufacturer but of different heat ranges can appear to be identical.
Bill Putney (to reply by e-mail, replace the last letter of the alphabet in my address with "x")
Yep, exactly. Good catch. What I intended was that they *appear* physically identical, and are physically interchangeable (same thread, same seat, etc.) but are not the same.
Thanks for all the input everyone! I already ran the truck with the RV17YC's, and it seemed to run very well (no pinging, smooth acceleration, smooth cruising), but I will check into the Autolite 25's.
On another note, I had posted to this newsgroup a few months ago about a
2 barrel conversion for this truck. I went to the '04 Mopar Nationals in Columbus, OH and found a "Super Six" cast iron 2bbl intake/exhaust manifold, carb, all the choke parts, kickdown linkage (although I do not need it)and breather in one package. So I will begin swapping those items in (after I clean them up) and I will post my results to the group.
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.