Log head mods and pricing

69stang_250

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Hey guys,

Just wondering for you guys that have worked with the log heads, how intensive have you or would you work on the log head for a performance build? What mods do you consider to be a must? And how much have those mods ran you?

I know a hardened seats, valve job, cleaning up the ports, exhaust devider, and a 2bbl conversion are those things that's nearly a must. I am just trying to see which is more cost effective. Building an engine with plans on putting an aluminum head on down the road or just taking what you already have an putting the aluminum head on now.

Just trying to help someone with a theoretical build at the moment.
They have a 200 that has about 10k miles on it since a rebuild, however that rebuild was 10 or so years ago.

Thanks for the input you guys!
 
Disclaimer: I AM NO EXPERT. This is just what I did...

I started with a C9 head so it had a larger intake volume. I cleaned up all of the combustion chambers myself with a Dremel, getting rid of all burrs and giving it a nice smooth (not quite polished) finish. I also port-matched the exhaust (leaving the exhaust ports just slightly undersized as this is supposed to help with avoiding reversion). I then used the Dremel again on all of the exhaust ports and gave them a nice smoothed surface. I probably spent 40-60 hours on this because: a) I've never done ANYTHING like this before, and b) well, I can be anal about things. I wanted to spend more time on it but I forced myself to stop....

At the machine shop: From there I had a direct mount conversion done for the Holley/Motorcraft/Autolite 2bbl carb. I also had 1.75/1.5 valves installed. I had them blend in the area directly below the valve but have not had the pockets worked (ie no work done around the valve guides). They also installed the exhaust port divider, new valve guides, and valve guides machined to accept the viton seals. I went with damped valve springs and the 1-piece retainers. I then had the head milled 0.070", taking the combustion chambers from ~61cc to 48cc. When I got the head back from the machine shop, I cleaned out (Dremel and burr) the oil passage on the rear stud for better flow after the cut. I then did a little work on the port divider and sent it back for a final dip. Then they put in all the new plugs. All of the machine work was done for roughly $800 with tax. I sourced all but the plugs and valve guides myself.

I did NOT do hardened seats. I'd been running my original head for 25 years (a number of them my teenage years where I drove it like I stole it) on unleaded gas and had no issues with the exhaust valves eating into the seat. Granted, that was with the stock springs so we'll see how this build holds up. But, from what I've read, Ford used better material for their cast parts than other manufacturers so they're not as susceptible to the same problems.

Hope this helps! :beer:
 
not that it matters:
is this a 200? a 250? what?
 
The 2 bbl direct mount is the biggest contributor so it would be the biggest bang for the buck. so that and a mild port and polish and you are there. You can spend more and get more of course if you have the money. Just an opinion from the budget minded type, like me.
 
If your final plan is to install the Aluminum Head then it maybe more cost effective to do it now. It all depends on how much of the work you can do on the Log head and your budget. If it's not in the cards right now then by all means Mod the Log head the good thing about them is that you could resell it in the future after you get the Aluminum Head. Good luck :nod:
 
Howdy Back 69stang and all:

1st some questions; What will this car/engine be used for? Location/elevation? Know that the Alloy heads are very scarce and very pricy AND very cool! They are the very best for high performance and high rpm living.

Is this a complete rebuild or head only?

What trans/drive train? cam, gearing, rpm range, ignition all tie together.

One item that has been overlooked so far is a back-cut on the intake valves. The extra 30 degree cut is very inexpensive- maybe $2.00 per valve and will pay dividends through out the rpm range.

IF you are going log, start with a '78 and later casting. Aim to maximize the compression ratio for the situation.

Keep the details coming as you refine and define your perimeters. But, I have to tell you I love these mind games.

Adios, David
 
CZLN6":lofey0mn said:
Howdy Back 69stang and all:

1st some questions; What will this car/engine be used for? Location/elevation? Know that the Alloy heads are very scarce and very pricy AND very cool! They are the very best for high performance and high rpm living.

Is this a complete rebuild or head only?

What trans/drive train? cam, gearing, rpm range, ignition all tie together.

One item that has been overlooked so far is a back-cut on the intake valves. The extra 30 degree cut is very inexpensive- maybe $2.00 per valve and will pay dividends through out the rpm range.

IF you are going log, start with a '78 and later casting. Aim to maximize the compression ratio for the situation.

Keep the details coming as you refine and define your perimeters. But, I have to tell you I love these mind games.

Adios, David
 
Has anyone ever open the log intake at each end, honed it, then close it up? To me, it looks like it has freeze plugs on both end. It will be later this year before I get the engine done. In the mean time, hoping to find a 79 or 80 head with the larger log volume and bigger valves. Any thoughts on opening the log at the end for the port and polish?
 
There are a few folks who have done it. Just remember that you shouldn't put a polish on the intake side. There are a number of article out there by David Vizard you should check out before tackling that.
 
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