Technical Hemi heads question

I’m rebuilding 241 hemi heads, my question is the exhaust valve guides have small holes in them to allow oil to lube the valve stem, and with the cam grind I’m using , the grinder recommended dual springs, so I got dual spring locators to use however when installed they block the oiling hole, so all that said , is that ok or do i need them drilled to match the guides oiling hole, I’ve found no info on this. Subject, I can leave them off but then my spring pressure will be way off from the intake side,that has valve seals, for the locators to protect , any body dealt with this before , thanks

 

Hi Robert,
My 1953 331 Chrysler had the same set up on the exhaust guides. The replacements did not. The machine shop I use is very familiar with the old engines. They said the later Hemi's did not have the holes. It was their opinion this was just an early attempt to keep the value cooled/lubed as MOPAR may not have been sure if they could eliminate this from the original design. Did you replace the original guides and the replacements also had the holes?
Joe

 

The holes don't matter, what matters is that you leave the valve guide seals off all Early Hemis on the exhaust side. I typically run .002 guide clearance on the exhaust side. It needs all the help it can get.

 

I ordered new guides from hotheads for the 241 and they have the holes , trying to decide if blocking them with the locator washers is ok

 

I plan to ream the guides to have 2 to 3 thousands clearance on the exhaust side, and wasn’t planning on seals on them just the intake ones reason I’m asking is I want locators on all to keep spring pressure the same as my cam is a 420 lift on int and exhaust, so are you saying blocking lube holes on exhaust won’t matter if clearance is 2 thousands ?

 

Reaming guides is a poor way to achieve clearance. Honing the guide is the way to go

 

Correct. Racer-X also brings a good point, you do need to hone the guides after reaming. Can tailor the clearance easier as well.

 

...0.420" lift does not need dual springs.....

 

My thinking is leave the holes Hemi exhaust guides run up hill instead of down hill like other engines

 

Thanks everyone

 

I bought new guides and they have the holes in them

 

I actually rough reamed them then honed them to speck