Stock CC volume for a 265 Spitfire Head? (can't find any previous posts)

[James_Douglas]

I was able to cc the head and got 120cc.

 

Well, That matches what I did on my stock NOS head many years ago.  Mine was an average of 116cc.  Some little more and some a little less.

 

The original thread is here: http://p15-d24.com/topic/40119-head-cc-notes/

 

Given the difference in fluids that may have been used and given the fact that here in San Francisco I did the CC on a typical day which is 55F-65F then I would say we got the same results.  What was the temp the day you did the CC ?

 

I also used Vaseline to seal the CC plate to the head.  This does add a very small about to CC figure. What sealing medium did you use?

 

I also had the hole on the very edge of the pocket and tilted the head up to that the hole was the highest place.  This allows for the air to come out better, it also minimizes meniscus issues.

 

I would say unless you KNOW it was shaved at some point, that is has not been shaved.  Try the milling recommendations that I worked out with Don's help.  Have you gotten a piston to deck measurement on this engine?

 

One thing I can tell you is that the Big Desoto 6 has a smooth idle and I think a big part of that was getting the CC variation between the cylinders to within 1CC of each other.  A lot of sanding took place! 

 

Good luck.  James

Edited March 9, 2016 by James_Douglas

[timkingsbury]

I can still buy it around,but since it is a violation of feral law to use it in vehicles driven on public roads,the airport insists you park outside the area where the gas pumps are,and hand carry your gasoline cans to the pumps. You also have to tell them the gas is for use in your lawnmower or similar off-road equipment.

 

No big deal for most people,but when you are old and have all sorts of physical problems,carrying a couple of 5 gallon cans of gas 100 yards is a major pain in the Obama. I mostly do it once a year right about the time I start cutting grass for what I think is the last time because the leaded gas is still good new spring when you start it  up again,and you don't have to rebuild the carburetor and flush out your tank and lines.

 

I'd buy it all the time if they would let me drive my truck up to the pumps to fill the cans,but they won't do that.

well as vice chairman of the olde geezer club, that is what kids and or neighbors kids looking to make a few bucks are all about.  Now truth is I have a tank at my

place and have it delivered, 500 cdn gallons at a shot.  lol.. got to keep those lawnmowers and chainsaws going!

[Powerhouse]

Well, That matches what I did on my stock NOS head many years ago. Mine was an average of 116cc. Some little more and some a little less.

The original thread is here: http://p15-d24.com/topic/40119-head-cc-notes/

Given the difference in fluids that may have been used and given the fact that here in San Francisco I did the CC on a typical day which is 55F-65F then I would say we got the same results. What was the temp the day you did the CC ?

I also used Vaseline to seal the CC plate to the head. This does add a very small about to CC figure. What sealing medium did you use?

I also had the hole on the very edge of the pocket and tilted the head up to that the hole was the highest place. This allows for the air to come out better, it also minimizes meniscus issues.

I would say unless you KNOW it was shaved at some point, that is has not been shaved. Try the milling recommendations that I worked out with Don's help. Have you gotten a piston to deck measurement on this engine?

One thing I can tell you is that the Big Desoto 6 has a smooth idle and I think a big part of that was getting the CC variation between the cylinders to within 1CC of each other. A lot of sanding took place!

Good luck. James

New cc I got was about 100cc with one at 104cc.

I used bearing grease and pressed the 1/16 inch plastic sheet down till it was as flush as possible. No leaks at all which I might have had the first go round. I averaged 100cc this time. One was about 104. It was about 65deg F and I used water.

[James_Douglas]

New cc I got was about 100cc with one at 104cc.

I used bearing grease and pressed the 1/16 inch plastic sheet down till it was as flush as possible. No leaks at all which I might have had the first go round. I averaged 100cc this time. One was about 104. It was about 65deg F and I used water.

Do the math and have your shop try the "one CC mill 0.0034" approach.  have them take 25% of what you need using the 0.0034=1cc and see how accurate it is.  If it pans out then do another 50% of what you need and check again.  If it holds on a one to one relationship then do the last 25% and/or less if it does not.

 

That is what I did on my head.  It was a pain to cc it and take it back to the shop 4 times (and pay 4 times) but with a NOS head I did not want to overshoot the mark.

 

James