72 TA : New Project

[VintageMusclecar]

(edit* you posted your above reply while I was typing this one, hence some redundancy)

The 2869 is also numbered as a UR4GP. A Platinum that's one step colder would be a UR5GP. A "standard" NGK that's 1 step colder would be a UR5. (Personally, I've never had any luck with platinum plugs in anything other than late model EFI stuff)

Loosely translated, the 2869's appear to be the equivalent of a R45TS and the UR5's would be the equivalent of an R44TS.

I would expect the engine to be done by 5K if it's in stock form. All of the "stock" Pontiacs I've ever worked with liked to be shifted <5K for best performance. I also recall that most of them liked a total timing figure of 30°-32° as well. (FWIW, I'm referencing some of these figures from a friend's `76 TA with a `69 RAIII 400 in it that's dipped into the high 12's in factory trim on more than one occasion)

Phil did your carb, didn't he? If so, I believe he normally richens them up just a tad, so the carb should be good to go. You might try richening up the trim screws maybe 1/8 turn and see if that makes any difference on the plugs.

Eric