I'm just wondering what spark plugs there running in their Hemi.I was running Ac Delco R43X65 but can't find them anymore. Thanks for any help.

What compression ratio, what fuel are you using and is this a street only or street and strip or race car only?
Hemi motors are all a little different, depending on the builder and application
BTW, I use to build, race and drive gen 1 and gen 2 hemi on the street and drag raced them also, I'm considering building a using Gen 3 now on a street project
My message is all three are different motors and do not like the same parts or tunes

Never heard of that number, and I was a sales rep for a Delco Remy warehouse for more years than I care to admit.

Iron block 10.5 -1 comp. 2x4 street car, alum. heads, pump gas.

I doubled checked the plugs I pulled out and your right.I went by the sheet the builder gave me and it's not real neat writing, I thought it was r43x65 but it's r43xls thanks.

it's been over 10 years since me and my friends ran 2nd gen hemi's.
we used to run NGK V grove plugs in our hemi's. if i remember correctly they were gr4 or 5.

I run NGK GR5 plugs in my 528 Hemi.

NGK 4554 (R5671A-8). 575" all aluminum pump gas motor.

I have also run both NGK R5671A-8's and GR5's, along with with Champion RN12YC and 10YC's. Seems to not matter. It runs and like all of them just fine on pump gas.

Thanks all for the info.

I would use either a Autolite #3923 or 3924. Champion # RC9YC or RN9YC, The C series plugs use a 5/8 inch spark plug body and the N series use the original 13/16 socket size and body. The R stands for resistor type plug, which is what you want to use on a street motor
Both of those Autolite plugs are resistor type also, the 3924 is a little hotter heat range than the 3923 is
It is always safer to use a colder plug when tuning a new motor than to hot of one, I would try the #3923 first and go from their
The colder plug will get blacker quicker andtry to foul out than the hotter plug will so try the new colder set first gapped at .035 or wider up to .050 and see if they are running clean or getting to brown or black from being to cold.
Then go ahead and try the hotter plug next and look at them and decide after that which one you want to run in the motor full time