View Full Version : Spark plug???

08-21-2007, 10:17 AM
I have an '02 MC Prostar 197 with the Predator 310hp motor. I'm told it's a TBI, not a Vortec. Is there any way for me to tell this for sure? There are no stamps or labels anywhere that I can find. The owner's manual reads both Vortec and TBI. Can it be both? I've found conflicting info on which type of spark plug to use. My manual calls for AC MR43LTS. I've read that these plugs are too long and may cause damage to the piston and that the AC MR43T is the ones to use. The ones in it now are AC 41-932 (twice the price). Any recommendations?

08-21-2007, 10:32 AM
Use the OEM plugs, AC MR43LTS....you can pick them up at NAPA.

08-21-2007, 11:19 AM
My 98 ProStar came from the factory with the MR43LTS plugs. I was running the MX 308HP engine, which should be the same as your Predator.................Tip.............Use a little Never-Sieze on the threads before installing the new plugs.