7r magnesium case machining check list
 

Hi everyone,

Just wanting to make certain I'm checking all the boxes for one of these blocks re machining for a hot 2.8 build:

align bore
case savers x 24
shuffle pin x 10
oil mod
deck case mating surfaces (how often is this done and is it always necessary?)
deck cylinder mating surfaces (how often is this done and is it always necessary?)



thanks all,
J

The oil by pass is already done on a 77.
Bruce

Well. I think there is the eyebrow the cylinders and boat tail argument.
Polish the crank.
Check the rods for egg shape.
new rod bolts.
oil pump?

I'm not exactly sure how many but when Ollies did my case, the also put case savers on the large studs along the web. I think there were two? Bruce could probably explain more/better.

They also added additional welding on the back side of the #3 inserts:
http://forums.pelicanparts.com/uploa...1393518264.jpg

Depending on how much they have to take off the case, the chain boxes may need shaving. And, what about the cam towers? Would the cam towers need to be trued?

Case
 

Do all the studs. Not just the barrel studs. Deck the through bolt surfaces and countersink the holes.

Have those been known to have issues as well?

I believe D.C is referring to countersinking the thru-the-case bolt holes to provide a place for the Viton (green) O-rings at both ends of the bolts? You chamfer the bolt hole as a grove for the o-ring to sit. Otherwise, the o-ring interferes with the washer which should lay flat against the case or is just gets squeezed out of place and doesn't seal. Yes, it's a known issue. Getting this wrong results in some pretty hefty leaks.

Great, thank you

Is Ollies the go to place to send cases?

Yes

Mag
 

Yes. But be sure to give them a complete list of what you want done. Super good guys but I think they are used to dealing with shops.

I'll be giving them a call this week. Taking my motor out tomorrow.

Ollies
 

One of the things they do that I really like is they measure the distance between the crank center line to the cylinder bases. Then they make base gasket shims as required to set your height back to the factory spec. Then you know you are starting with the factory spec for setting CR and deck height.