WTK head M38

buzzk · Post by **buzzk** » Sat Dec 28, 2013 6:06 pm

Want to know location of bypass nipple in head its 1/4 pipe thread I have to drill and tap the head for the nipple thx buzz

Moved from parts wanted board here to technical questions board. Moderator

Post by **wesk** » Sat Dec 28, 2013 7:44 pm

If you do not have the 800376 head casting which came with just the raised boss for the bypass port or already drilled bypass port you run the risk of weakening the earlier heads or not getting the water jacket location correct.
The top 1/5th of the port is in the curved section of the head which is likely why the raised flat boss was added.

Post by **wesk** » Sun Dec 29, 2013 9:36 am

Buzz added some info to his original question:

yes I do have the correct boss on the head just no hole

Post by **wesk** » Sun Dec 29, 2013 11:47 am

And here are the numbers:

For height I would use the measurement from the top of the boss since you have no idea how many times your head has been shaved (machined for flatness)