difference in R44T and R44TS spark plugs
 

Hey all like the title says? I was trying to get my newly rebuilt Fuel injected (TPI) 327 running. I had the usual unknowns of the new engine plus the fact I bought a used TPI. I then proceeded to cut the wires out I didnt need and spice some length to the 30 or so I did need. So you can see I was a bit leary about the new setup. Anyway a had a bad air intake temp sensor so it was running RICH it went down hill from there and couldnt get it started. I checked and replaced the necessay items. Once I finally checked the spark plugs for spark (had timing light on so there was fire to the plug) it had a very weak spark. I had just cleaned them (they were new prior to the rich run) to no avail. I grabbed my old ones sitting from the tear down a year ago and stuck them in. It now runs great!
Anyway my old ones were the R44TS the new ones were R44T. I was running HEI before and of course am now.
Could that have been part of the problem?
Thanks
DAve

I believe R44 is a colder plug and the TS is "tapered seat" that means they don't use the washers or "peanut plug heads". By the part number given they both should be AC Delco spark plugs. So were you trying to put on spark plugs that have washers on them (should have taken a 13/16" socket to put them in)? If the plugs look different then that is your problem, if not, I'm not really sure what you had wrong.

AC has a code system for their spark plugs. The difference between the two plugs is that one has an extended tip and the other does not.

R44TS

R= Resistor
4= 14 MM
4= Heat range
T= Tapered seat
S= Extended tip

The R44T is the same plug except it does not have the extended tip.

For further information, check this site out.

Jim

http://www.acdelco.com/html/pi_plugs_ident.htm

And the X is a wide gap so a TSX would be tapered, extended tip with a .060 gap.