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![P5049(8)040 Flat Top Piston for 1959-1966 Pontiac 6.4L [+0.040 in. Oversize]](https://www.jegs.com/images/mini_750/400/416/416-p5049(8)040.jpg)
Vehicle Info NeededENGINETECHPART NUMBER: 416-P5049(8)040
P5049(8)040 Flat Top Piston for 1959-1966 Pontiac 6.4L [+0.040 in. Oversize]
$36899
Ships on 09/17/2026
Lowest Price GuaranteeGM
Piston1959-1966 Pontiac 6.4L Flat Top Piston Size: +0.040 in. Oversize Set of 8
The Enginetech P5049(8)040 is a replacement piston for 1959-1966 Pontiac 6.4L. 1.700 CH. w/ 10.1:1 CR. Use R40638 rings engines, sized at +0.040 in. Oversize. Engineered to OE specifications for reliable combustion chamber performance.
Enginetech P5049(8)040 Piston Features:
- Fitment: GM/Pontiac, 389 ci
- Size: +0.040 in. Oversize
- Engineered to OE specifications for direct replacement
Part TypePiston
BrandENGINETECH
Package Height4.5
Package Width9.25
Package Length18.25
Weight15.5 PG
Part CategoryReplacement Parts
Compression Height1.700
Size+0.040 in. Oversize
QuantitySet of 8
Oil Ring Thickness3/16
RemanufacturedNo
Bore Diameter4.063
Piston StyleFlat top
Piston Pin Outside Diameter0.9804
Second Compression Ring Thickness5/64
Top Compression Ring Thickness5/64
Piston MaterialCast aluminum
FitmentGM/Pontiac
Part FitmentDirect Fit
Vendor Part NumberP5049(8)040
Package Qty1
Package TypeEA
No Questions
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