The beloved 318

[Dartswinger70]

I would believe the cylinder failed and that's how the piston broke...I mean no one knows but its a possibility over the piston just coming apart...there was that fella who ran an aftermarket crank in his 318 and the crank snout broke at high RPM, Uncle Tony piggybacked the guys video saying the timing chain broke...point is there's two stories for every story...

 

[Illahe]

9.5 is plenty for a street build, and quench is no problem with a typical edelbrock knockoff head, or a magnum head.

Okay, a stated I'll be using oem castings, 587 or 345. Surely you have more experience than I with Hypereutectic builds. They're not for me...

 

[Illahe]

I would believe the cylinder failed and that's how the piston broke...I mean no one knows but its a possibility over the piston just coming apart...there was that fella who ran an aftermarket crank in his 318 and the crank snout broke at high RPM, Uncle Tony piggybacked the guys video saying the timing chain broke...point is there's two stories for every story...

Sh** happens... I wont run them again.

 

[NC Engine Builder]

Okay, a stated I'll be using oem castings, 587 or 345. Surely you have more experience than I with Hypereutectic builds. They're not for me...

What kind of compression are you shooting for?

 

[Illahe]

Incorrect. And your definitely wrong about hyper pistons "shattering" they only do that due to improper piston to wall clearance (typically from old school machine shops who are to stubborn to read) not following ring gap requirements (see above) I've built HUNDREDS of engines with hyper pistons with ZERO failures.

The two 9:1 hypereutectic 360's we assembled are good motors, hence nothing fancy. I'm not a machinist, just a hobbyist and don't challenge your experience with hypereutectic builds. I choose not build another short block with them.

 

[Illahe]

What kind of compression are you shooting for?

The motor was just a mule to shake out my car. 10:5 was what I suspected. We run in 4700-6500' air so compression is hard to come by. For a street combination I run + 10~12 cc Ross in my 308 head 360 and it would like a pinch less with a 242 solid on 110 (edited) in at 106.

Currently, there are some small blocks taking up floor space and I would like to kick around with some builds considering a 340 D/SA went 11.20 and a 318 in GT/? went 10.50 with oem head (castings...) in air well over 5500'.

Like I said, I'm a hobbyist.

 

[NC Engine Builder]

The motor was just a mule to shake out my car. 10:5 was what I suspected. We run in 4700-6500' air so compression is hard to come by. For a street combination I run + 10~12 cc Ross in my 360 and it would like a pinch less with a 242 solid on 108 in at 106.

Currently, there are some small blocks taking up floor space and I would like to kick around with some builds considering a 340 D/SA went 11.20 and a 318 in GT/? went 10:50 with oem heads in air well over 5500'.

Like I said, I'm a hobbyist.

Cool! One thing to keep in mind, if your going to try to get quench with a oem open chamber head, is its EXTREMELY likely you will need to machine the chambers. Lots of times the depths vary cylinder to cylinder, and sometimes sloped.

 

[Illahe]

Cool! One thing to keep in mind, if your going to try to get quench with a oem open chamber head, is its EXTREMELY likely you will need to machine the chambers. Lots of times the depths vary cylinder to cylinder, and sometimes sloped.

Thank you for your help! The La blocks are often culled, (if that's the right word). The oem cylinder chamfer on 1 360 look pretty rough, almost to the top of the ring. Some blocks look better than others.

Thanks for the heads up on the cylinder heads. I ordered some silicon or epoxy mold kit to copy the chambers. The motor that took a s*** was EQ headed (New Zealand Castings).