Cast block / aluminum heads O-ringing question

moving from a 10-71 to a 14-71 blower in my T/D this year so moving from a MLS style gasket to copper and O-rings. My blower guy said since I’m running cast (Dart Big-M) block (wet) and aluminum heads I should o-ring the block and not cut a receiver because of the differences in materials. I know most run o-ring and receiver combo but most I’ve talked to run aluminum block and heads. Gasket will be .050 thick, probably between 24-30 psi of boost with 10.6:1 compression.

 

What size head studs?

 

7/16 (stock size) with the extra lifter valley studs. Was making 17-20 lbs of boost with the 10-71

 

Put the wire in the head, put receiver groove in block.

 

You will have more power than what I had back in 1978-80. We used 1/2" head studs on a truck block so it could serve as a back up for a Rodeck 481. We ran both iron and aluminum heads on the truck block w/o a receiver w/o issues with about the same static compression; but you have a lot more blower (and a much better iron block).

 

Currently I am running Lb-22 and F11 8-71 at 70% over with high compression ratio, On a 3 engine modified tractor. I currently have 1 Dart Big M block and 3 KB olds blocks with Dart Big M 410 heads and Brodix BB2 Extra CNC heads.

I have run all combinations of O rings over the years. It is important to run the valley bolts. You can run the wire in the block and receiver groove in the head and get away with it. If you want to be really sure you do not have a problem put the wire in the head and receiver groove in the block.

If it is the receiver groove in an aluminum head after a while the sharp edge of the head will round over and the seal will not be as good.

with the receiver groove in the block you will have too pry the copper gasket out of the block receiver groove which makes one less worry about a leak.

BTW I run both 7/16 and 1/2 head studs.

Not sure what the "dissimilar materials" has to do with it. An aluminum block you are still clamping against steel liners.

My thoughts, no receiver groove, it will not hold.

 

I'd put the wire in the heads.

 

.041 stainless wire in the head, receiver .050 wide receiver in the block/sleeve about .020 deep. Running inner studs/bolts very important. Torque from the outside in and you will have no problems. Just try to copy whatever the hemi stuff is doing. It works......I run 40 lbs of boost with KB Olds block and Dart big chiefs and have burnt a piston or two and gasket sealing area looks like I just put it together..