[gtofreek]

Worked on the heads a little more a couple weeks ago. I had to finish up some heads I was doing for someone else. Now I can get back to these. I ended up grinding through the roof, in between the spring pad, and the rocker stud boss. I also worked the short turn some more. I almost got all the turn over out of it. When it turns over now, it only looses about 5 CFM, then starts getting it back, and then some, when opening up the valve more. It peaked about 279 CFM @ .800". Hit 265 CFM @ .450", then turned over and dropped to 260 @ .500". Don't really think I'll be able to get them to 180 CC's.

[HWYSTR455]

Bummer. At least where you broke through you can build it up from the outside and it will probably be ok. Sure that was a palm-forehead plant when that happened!

.

[steve25]

Paul one thing I would do since this is just your mule head in regards to porting would be to fill in the chamber on the short turn side the you layed back with epoxy little by little.

Unfortunately the result of doing that lay back / unshrouding work is to make the short turn height that you have ( which is already marginal!) act even shorter as that lay back increases the already too high velocity at the lift point where your seperation takes place.

You need to view /think in terms of that whole area ( including any angles, be they valve angles or chamber lip angles )as being part of the function of controlling the port velocity of the air mass coming over that short turn!

The area you need to shoot for getting the most flow at is at the point of half the total lift of your cam, as that's where the valve spends averages most of its open time at!

Even if for example we could port these heads to hit 325 CFM at say .800" lift but at .400" lift the head only flowed 260 cfm the motor would still never make the HP number you would think you would have by running .800" lift at the valve to reach for that 325 cfm!

Much bigger duration numbers of a full on racing cam would let that suposide 325 cfm do its HP thing as we would expect!

[gtofreek]

Originally Posted by HWYSTR455

Bummer. At least where you broke through you can build it up from the outside and it will probably be ok. Sure that was a palm-forehead plant when that happened!

.

It's a junk head, so it doesn't matter.

[gtofreek]

Here are some pics of the block. I de-burred it around the mains and oil pan rail. Around the lifter bores also. I forgot a section of casting flash on the front of the block. Will have to get rid of that too.







Here's some before pics.

[gtofreek]

Here are some pics after I had the block burned and shot peened. Note how clean the water jackets get.

[HWYSTR455]

Wow that is clean!

.

[gtofreek]

Worked on the crankshaft for a while today. I started bullet nosing the leading edge of the counterweights. Then I removed casting flash around the rod pin. Also I created a larger radius around the round pin cross section area. I cryo treated this crank last week, then had it magna-fluxed. I had planned on taking a couple pics of it being magged, but totally forgot to do it. Here are some pics of it coming out of the Cryo tank, still covered in frost.

[gtofreek]

Here are some pics of the crank getting a make over. After I'm done, I am getting it shot peened. That will blend it all in nice, remove all the rust, and make it look like a brand new casting. Only after all the de-burring, it will look more like a new billet crank.

[gtofreek]

[gtofreek]

[gtofreek]

Put a nice little chamfer on the edges.





After polishing.

[gtofreek]

Then I worked the rod pin, and went from this;





To this;

[gtofreek]

[gtofreek]

[gtofreek]

Burned through all my sanding disks, so I need to get more.

[Squidward]

Some artwork there!

Question on the cryo stuff... Is it a liquid N2 dip, with a super quick cool? How do you return it to ambient temp, quickly or slowly?

Don't worry, I won't steal your trade secrets! My backyard cryo chamber is at the shop getting some work done.

I haven't played with cryo-ish stuff since being in the Navy at the shipyard where we would have to do a freeze seal on a section of unisoloble piping. I had friends who would freeze cockroaches, oranges, and potatoes while sitting freeze seal watch. Sounded like fun.

[gtofreek]

The process takes the temp down at a rate of 1°f per minute, so it takes 6 hours to get down to temp. Then it soaks in liquid nitrogen for 20-24 hours, then comes back to room temp at a rate of 1°f per minute also.

[gtofreek]

Here is a selfy of me in my grinding attire.

[hurryinhoosier62]

I like the gas mask!! Once again, I am awed by the quality of your work, Paul. How wide of a radius are you planning on using on the main and rod journals?