226 milling guidelines and cam question

[mainline331]

Hello- I am new to this forum, but read many of the threads, and it seems quite useful. I am the owner of a daily driver 50 sedan with the flat six and three speed, entirely stock running gear. I am currently overhauling the motor and was wondering if anyone could give some advice on milling my head to raise the compression about a point or so, or formulas for how much to mill ...
With that in mind, I am considering having my cam ground a little bigger to utilize the increase in cylinder pressure. Any recommendations?
Any help is appreciated, and I look forward to this message board.
-James

 

[flatford6]

Sixty thousandths mill from stock will give you about 1 point of compression gain. This assumes that the head hasn't been milled at some time in it's 59 year past. The thickest head measurement from the top of the head bolt bosses to the combustion chamber side that I have found is 1.890 inches. If your measurement is less, the head may have already been milled some. Always check for valve to head clearance after any milling is completed. Use modeling clay strips over the valves for this. For cam grinds, most cam grinders have flathead v8 grinds that can be ground onto the 6 cam. Clay Smith grinds a 260 degree, .333 lift, 220 degree @ .050 lift 3/4 cam. Isky grind #44-3/4, 250 degree, 364 lift, 220 degree @ .050 lift might be a better choice because of the higher lift. Use only the aluminum cam gear, the fiber one is marginal at best. One final hint, make sure the distributor is delivering the full advance you will need to make the most power. The stock system is very poor at best. Centrifugal advance for a full throttle curve with vacuum advance for part throttle economy is your best bet. Incidently, the 6 equipped 1950 Ford was almost 1 second faster 0 to 60 mph than the similarly equipped 1950 v8 Ford. It was the fastest 0 to 50 of any 1950 stock car Tom McCahill tested for Mechanix Illustrated and was written up in the June 1950 issue. The 6 also won the Grand Canyon economy run by over 2 mpg over Chevy and Plymouth that year.

 

[mainline331]

Hey thanks a lot. Very helpful. So as you said, my head measures out to 1.75, and I have a spare head that was exactly 1.89. Taking it in this weekend to buzz off .060. I havent talked to Isky yet, but I did talk to schneider, who has several profiles that look interesting, such as a 220 @.050 (260 gross)/.355 lift and a 234/.365, which might be better with a little more compression. They have them on their website: http://www.schneidercams.com/cams/51a.htm
Do you have any input on lightening the flywheel? Seems like since these motors are torquey by nature that it might help accelerate a little quicker without sacrificing too much off the line. I am considering this since I am going to the machinist tomorrow.
Although I may not get to it right now, I am planning to use a mustang t-5 with a chevy s-10 tail shaft (better shifter location for the shoebox), to help keep the motor in its happy (low) rpm range with more gears.....and of course have overdrive. The s-10 has to be older though, as most are now electronic speedos. I also need to make an adaptor that spaces the trans back a little, but shouldnt be too difficult.

 

[flatford6]

Sounds like your plan is good. Are you going install dual exhaust and multiple carbs? If so you could probably use the bigger of the two cams you mentioned. Or are you going to keep it looking stock on the outside? Incidentlly your 1.750 head already has about .140 off it already. Concerning flywheel lighening, about 10 lbs can be removed reducing it from about 34 lbs to around 24 lbs. It would then need to be rebalanced. Your plans for a t-5 should work real well what with the overdrive and lower first gear. You can use your existing bell housing and a machined aluminum plate. Check to make sure the throw out collar does not slide off the end of the end of the front bearing retainer. Are you going to do any porting, the ports have some really ugly protrusions around the valve guides. Big intake valves? The stock allignment of the intake and exhaust ports to the manifolds is pretty bad and could be easily ground into alignment.

 

[mainline331]

For now I plan on using a 32/26 weber. I would like to split the manifold, I saw a thread on this site that said you can use a truck manifold combined with the car manifold. Are you familiar with this? What do you do for the center two ports where they share a bolt? Regarding this, is it really advantageous to split them, or is it better to keep them together for the scavenging effect?

Moving along with my project, my block is at .060, so might be looking for a "future" block to keep around and play with as I get this one up and running. I noticed the mention of a truck 254. What is the bore and stroke of this? Is it otherwise interchangeable? I might start looking around....

Also, interesting to note that my motor was missing the oil slinger....?
I need to come up with one.

 

[mainline331]

For now I was thinking of using a 32/36 weber, or a larger single, maybe from a ford 300, or mopar 225 though I have yet to measure one to see the throttle bore size.
Looks like it would be a fairly straight forward caper to split the intake in two, for dual carbs. I wonder if there is an advantage/disdvantage to seperating them, or would it be better to equalize them by keeping the section where the original carb was.
I would like to split the exhaust manifold, I saw a thread on this site that said you can use a truck manifold combined with the car manifold. Are you familiar with this? What do you do for the center two ports where they share a bolt? Regarding this, is it really advantageous to split them, or is it better to keep them together for the scavenging effect? If so, I guess I could just add another dump.

Moving along with my project, my block is at a sloppy .060, so might be looking for a "future" block to keep around and play with as I get this one up and running. I noticed the mention of a truck 254. What is the bore and stroke of this? Is it otherwise interchangeable? I might start looking around....

Also, interesting to note that my motor was missing the oil slinger....?
I need to come up with one.

What are you working on / driving?