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Discussion Starter · #1 ·
I have a problem with one of my 289 cylinder head, he cracked.
My cylinder head is a rail type, the hole of pushrod are "round", and I use Rockers rail type.
Now one of my cylinder heads has cracked and I have found that there are two types of pushrod holes.
I can get a cylinder head but they have the "slots" instead of the round holes, (non rail type).

My doubts and questions are:
What is the only difference between these two types of cylinder head?
Is it just the slot holes vs round holes?
Can I machine and place the round hole and use my rail type rockers?

I need help because I live in Portugal and I don't have the opportunity to get a rail type cylinder head here.

Regards,
Filipe Neto
 

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You may run into several problems with this "conversion". Drilling out the guide holes in the head is fine for getting rid of the built in guide slots in those castings but there are other considerations. The casting you are wanting to drill out is of an earlier vintage and probably has shorter valves overall and also probably does not have enough valve stem above the retainer to allow the use of rail rockers.
If there is enough valve stem for the use of rail rockers make sure to remove a valve and measure the length otherwise your geometry will be off and you will have other problems.
Also these heads will most likely be smaller chambers so you will have higher CR.
 

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Discussion Starter · #3 ·
You may run into several problems with this "conversion". Drilling out the guide holes in the head is fine for getting rid of the built in guide slots in those castings but there are other considerations. The casting you are wanting to drill out is of an earlier vintage and probably has shorter valves overall and also probably does not have enough valve stem above the retainer to allow the use of rail rockers.
If there is enough valve stem for the use of rail rockers make sure to remove a valve and measure the length otherwise your geometry will be off and you will have other problems.
Also these heads will most likely be smaller chambers so you will have higher CR.
Thanks for the answer.
So you're telling me that heads are different?
I've noticed that some cylinder heads have a different combustion chamber, but I didn't know I could change the dimensions of the valves.

So, even though I have the same combustion chamber, I can't do the transformation?

Regards,
Filipe Neto
 

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Thanks for the answer.
So you're telling me that heads are different?
I've noticed that some cylinder heads have a different combustion chamber, but I didn't know I could change the dimensions of the valves.

So, even though I have the same combustion chamber, I can't do the transformation?

Regards,
Filipe Neto
Yes, the heads are different. Both are 289 of course but 1965 was last year before Ford went to rail rockers. I wouldnt worry too much about the compression change on your engine but probably not a good idea to have different size chambers on one side of engine and not both. Even if the head you are replacing looks like the same type of combustion chambers as the one you want to use (1965) the smaller kidney shaped chambers on these 289 heads came in 4 different CC sizes. All pretty much look the same to the naked eye.
The rocker geometry is your biggest issue. If you have '65 castings, the short valves, which you probably do, then you have to use the short push rods and the non rail rockers. This will make everything right. Just convert your 289 to these '65 heads on both sides.
Ford only made 2 push rods for SB ford, the short one and the long one. The short one is used in all 221-289 up till rail rockers were used. Easy to spot these heads because the valve stem does not protrude above the retainer enough for a rail type rocker. The shorter push rod is used to maintain the proper lift aspect and maintain the correct alignment on the tip of the valve.
 

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Discussion Starter · #5 ·
Yes, the heads are different. Both are 289 of course but 1965 was last year before Ford went to rail rockers. I wouldnt worry too much about the compression change on your engine but probably not a good idea to have different size chambers on one side of engine and not both. Even if the head you are replacing looks like the same type of combustion chambers as the one you want to use (1965) the smaller kidney shaped chambers on these 289 heads came in 4 different CC sizes. All pretty much look the same to the naked eye.
The rocker geometry is your biggest issue. If you have '65 castings, the short valves, which you probably do, then you have to use the short push rods and the non rail rockers. This will make everything right. Just convert your 289 to these '65 heads on both sides.
Ford only made 2 push rods for SB ford, the short one and the long one. The short one is used in all 221-289 up till rail rockers were used. Easy to spot these heads because the valve stem does not protrude above the retainer enough for a rail type rocker. The shorter push rod is used to maintain the proper lift aspect and maintain the correct alignment on the tip of the valve.

Thank you very much for your availability.

So, if I want to use the this two cylinder heads I have from 65, I have to change (have to buy) new pushrods and new rockers suitable for these heads, (short pushrods and non rail rockers)?.
Tell me something, are the valves (intake and exhaust) different from mine too?

Can you tell me where i can find these shorter pushrods, can you send me a link? I can't find it for sale. On "www.rockauto.com" (that's where I usually buy) I can't find any different for 4.7L 289, or do I have to change the engine?

I would like to buy 2 used cylinder heads from the year of my engine (with the round pushrod holes), but I can't find someone who has them in the USA and do the ship to Portugal.

Thank you again for your attention,
Best regards,
Filipe Neto
 

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Thank you very much for your availability.

So, if I want to use the this two cylinder heads I have from 65, I have to change (have to buy) new pushrods and new rockers suitable for these heads, (short pushrods and non rail rockers)?.
Tell me something, are the valves (intake and exhaust) different from mine too?

Can you tell me where i can find these shorter pushrods, can you send me a link? I can't find it for sale. On "www.rockauto.com" (that's where I usually buy) I can't find any different for 4.7L 289, or do I have to change the engine?

I would like to buy 2 used cylinder heads from the year of my engine (with the round pushrod holes), but I can't find someone who has them in the USA and do the ship to Portugal.

Thank you again for your attention,
Best regards,
Filipe Neto
I am sorry about your predicament. I was assuming that wherever you got this replacement earlier style head from you would also be able to get the rest of the valve train parts, push rods and rockers. I was thinking you tore this off a used engine somewhere.
 

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I am sorry about your predicament. I was assuming that wherever you got this replacement earlier style head from you would also be able to get the rest of the valve train parts, push rods and rockers. I was thinking you tore this off a used engine somewhere.

Let me check my inventory. I may have enough to make a set for pushrods and rockers. I may even have your original head but shipping the small parts would sure be more economical, I would think......
 

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Let me check my inventory. I may have enough to make a set for pushrods and rockers. I may even have your original head but shipping the small parts would sure be more economical, I would think......
Well, I have a big box of pushrods but they are all the late model long ones. I do have quite a few of the non guided rockers however.
I also have a pair of '66 289 core heads, casting #C6AE. What is the casting number of your cracked head?
 
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