: pistons



jwcummings
04-03-10, 10:23 AM
Ok if I get my pistons bored out do I have to change my heads?

Submariner409
04-05-10, 09:26 AM
According to the GM service manual there are no service replaceable (oversize) pistons available, but someone does make a couple of couple of oversized piston sets - ask CHRFAB. A Northstar does not normally need new pistons, just rings at some incredibly high mileage, and even then there is no process for honing (glaze breaking) each cylinder.

Why would you try to bore the cylinders and, no, cylinder boring does not require new cylinder heads.

jwcummings
04-05-10, 11:59 PM
rockauto auto has these 1990 CADILLAC SEVILLE 4.5L 273cid V8 MFI (3) OHV : Engine : Piston Price Core Total
SEALED POWER Part # 573P {Cast Piston}
Cast; 2 - 1.50mm Groove, 1 - 3.00mm Groove, 1.240 CD, Recessed Head .020 deep x 2.940 dia., 0.8661" Pin Dia.
Choose Size: 0.25MM Oversize {8}+Standard {8}+
+ Sold in packs of {x}; Price reflects cost of each individual item, not the pack

$34.79 $0.00 $34.79
SEALED POWER Part # W573P {Cast Piston - Individual}
Cast Piston - Individual; Cast; 2 - 1.50mm Groove, 1 - 3.00mm Groove, 1.240 CD, Recessed Head .020 deep x 2.940 dia., 0.8661" Pin Dia.
Choose Size: 0.25MM OversizeStandard

Submariner409
04-06-10, 09:55 AM
OK, my mistake - I'm still in the Northstar world, not the 4.5.

but still, no - you don't have to change heads.