5 replies to this topic

[UCSLE]

I am looking at putting a red head on a blue motor after finding problems with blue motor head i had

 

Have seen threads where people are talking about re drilling the block for the water passages but none about re drilling the head instead

 

If i re drill the red head will it go into the water jacket ? has anyone seen it done ?

 

Re drilling the head seams like a better option for more and better water flow into the head

[N/A-PWR]

Great topic Troy,

 Probably too expensive to cut open a Red & Blue Head  ,

to see if the water chambers at the holes are the same or different, hmm. 

[RallyRed]

Thinkin' Bomber went into some detail in this?....
https://www.gmh-tora...inder-head-101/

[RallyRed]

.

Edited by RallyRed, Yesterday, 07:06 PM.

[N/A-PWR]

Bomber does say this:

You can either drill your block out to suit your head and run a corresponding gasket, or drill the head out to suit the block and run a corresponding gasket. 

Here:

https://www.gmh-tora...01/#entry798129

 

So if Bomber says so,

 then it is right so,

 as he wrote the 101 book. 

 

p.s. we also know the Blue Head has thinner wall castings,

 so this is something to think about, hmm. 

 

Thinkin' Bomber went into some detail in this?....
https://www.gmh-tora...inder-head-101/

Edited by N/A-PWR, Yesterday, 07:57 PM.

[Muzza]

I fitted a blue head onto a red block, 

using the head gasket as a template you need to drill water passages in the black, and then tap and plug the holes no longer needed

the same will apply swapping red head onto blue block

BTW I have a blue 173 head with big valves, 1.750, 1.5  available if needed, and a rebuilt black 3.3 head available at Christmas