intake manifold threads

[vader6]

I will be chasing the threads on a newly powdercoated intake manifold and I need to know all of the tap sizes required...anyone have this info?? thanks

 

[PSID6]

This is by memory but pretty sure there are three sizes M8 1.5 and 1/2-14 NPT, 3/8-18 NPT

 

[earlbrown]

3/8-16 threads are in the heads not the intake.

The rule is any TR specific parts are metric. Any plain old Buick parts are SAE.

It can get tricky on places like the crank hub and exhaust manifolds where you have both.

 

[pacecarta]

when he posted 3/8 hes talking about npt for the sensor holes and 1/2 npt for the heater rail fitting hole ,i think theres also 1/4npt

all the bolt holes for plenum, fuel rail , heater rail clamp , coil bracket, thermostat clamp , vac line under throttle body , egr valve stud are m8x1.25 not 1.5

 

[vader6]

when he posted 3/8 hes talking about npt for the sensor holes and 1/2 npt for the heater rail fitting hole ,i think theres also 1/4npt

all the bolt holes for plenum, fuel rail , heater rail clamp , coil bracket, thermostat clamp , vac line under throttle body , egr valve stud are m8x1.25 not 1.5

that's what I needed, thank you!! M8x1.25