Re: [T3] Heat gauge (head affect)

["Martinez, Leon" <martinezl@ftscpac.navy.mil>]

Jim wrote,

- Leon has done more, and better, data taking than anyone else I know. This
is 
- really useful stuff to know. I wonder if the combustion chamber volumes
are all 
- the same on these heads. That would change the compression ratio and make
a big 
- difference, and might explain some of his observations.  

============================================================================
======

 Most of the data given in that last message was from memory,
if more exact info needs to be looked at, look into the archives 
of this forum, I recorded information as I destroyed engine parts.

All compression has been the same, with the same size stock 
combustion chamber for a bug with the lip or step casted and 
machined into the combustion chamber. the only time I had a 
different compression was when I did the ultra low compression 
that Berg recommended (75 lbs on all four) after that and a set 
of new heads, I increased it to around 110 lbs by removing the
shims from the cylinders in order to meet the stock/tighter 
deck hight. I was tired of slow take offs (Still slow but 
better, it is all relative though).I never really checked 
the combustion chambers with the special tools, I have always 
gone by the deck hight, same amount of baby oil that fits the 
combustion chambers and the same pistons, rings, and cylinders 
that I bought on the first rebuild in 1999 (upgraded with second 
ring from Total Seal), I never recrossed hatched the cylinders, 
just tried to place the rings in the same position as always, 
may not be correct but I did that and still got 110 lbs and 
still have 110 lbs compression ,(knock on wood) . Cross hatch 
still visible after 75000 miles, last August, when Mofoco head 
was replaced with a Mexican VW head.  

I always use Semisynthetic oil (20W-50) from Valvoline, 
change oil almost monthly or 3000 miles. I do not know if this 
affects compression or wear , just more data.

Engine pistons, cylinder, top ring and oil rings have 
around 90,000 miles. the Mexican head has around 15,000
miles since last August, I hope it proves to be as durable 
as I suspect.



LEON MARTINEZ


69 SQUARE
73 FASTY
67 FASTY

  

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