Spark Plugs - What did they send me?

[jnickell41]

I ordered eight AC Delco R44TS plugs from Rockauto. Due to inventory levels they sent me two from one warehouse and six from another. Upon closer inspection it appears these are two different plugs, I'm trying to identify what I have, if they all would fit, or which ones I should send back.

Six boxes are labeled "BR44TS" other two boxes are labeld "R44TS". All eight spark plugs are labeled "R44TS". The plug on the right in the picture is from the "BR44TS" box. Pretty clear there are some physical differences between the plugs. Would both types fit my stock 350 TBI? Or should I send one set back?

Thanks

[WarpathEngineering]

For what it's worth, AC's spark plug chart says that the "B" designates a series gap. A google search turned up an old GM patent for a "series gap spark plug" (https://www.google.com/patents/US3737708). All that being said, I'd be willing to bet that it's the same plug and will work fine in whatever a R44TS plug is spec'd for.

[slotard]

Looking at it, I sure don't think they're the same plug. Doesn't mean they aren't compatible, but I'd email them.

[jnickell41]

Yeah, I emailed Rock. Below is part of their response.

"I spoke with an AC Delco technician about this issue and he stated that they would not recommend mixing these two plugs but the thread reach, pitch and seat angle should all be the same so they should work."

Rockauto has already dispatched 6 new spark plugs to make a matching set.

I think the interesting thing about this is both spark plugs are labeled "r44ts"

[slotard]

So the plugs themselves are marked the same but the boxes are marked differently? That's odd.

[MalibuSSwagon]

It's nice that they proactivly resolved the issue!

[enaberif]

LOL I've had weird **** like this happen before. I once ordered Moog ball joints and got some weird 3rd party stuff in a 3rd party box.

Rock Auto is good for fixing mistakes though.