Closed chamber heads straight swap from open?

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83slimer

Well-known member
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Apr 9, 2015
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Location
Nova scotia Canada
My Car
1973 sportsroof mustang
Hi Guy's

I picked up a set of complete Closed chamber heads, DOAE , I currently have a 72 block with open chamber heads, My question is is it a straight bolt on swap from open to closed chamber heads? Should I get new head bolts or am I ok to reuse my old ones? I Already have a complete gasket set with new head gaskets. Fel-pro.

Since they are not installed yet I'm at least going to put in new valve seals Now rather than waiting to find out later. I need to swap over my Studs Guides and harland sharp rockers. Are there positive stop valve seals available? instead of the umbrella type? The gasket kit I got for a 89 302 had both types I liked the press on style with the collar.

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If the bolts and threads look good I always reuse. Had gotten positive stops and had trouble installing them. Not sure if they stayed in place and are working. I Would use umbrella next time if there room.....

 
On an engine with unknown history I prefer to use new bolts, even though it is generally acceptable to reuse them.

Other things you need to consider is having hardened valve seats installed, valve guides, and replace the stock two-piece multi-groove valves with one-piece valves. Have the machinist machine the guides for the good seals and check the mating surfaces for straighteness and touch up if necessary.

Check your cylinder bores for taper and ridge. Worn cylinders and/or worn rings will allow more blow-by with the increased compression.

If the pistons are dished and not flat tops you will not realize the full benefits of the quench heads.

 
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On an engine with unknown history I prefer to use new bolts, even though it is generally acceptable to reuse them.

Other things you need to consider is having hardened valve seats installed, valve guides, and replace the stock two-piece multi-groove valves with one-piece valves. Have the machinist machine the guides for the good seals and check the mating surfaces for straighteness and touch up if necessary.

Check your cylinder bores for taper and ridge. Worn cylinders and/or worn rings will allow more blow-by with the increased compression.

If the pistons are dished and not flat tops you will not realize the full benefits of the quench heads.
My Motor is still fresh less than 3000km since it was completely rebuilt so the bottom end stuff should be good. Block was decked and my open chamber heads also. Are the hardened valve seals a MUST? Since my motor is still complete I think I'll leave it alone for now and get these heads built properly before doing the swap. Or just offer them with the car if I ever sell it.

Thanks

 
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On an engine with unknown history I prefer to use new bolts, even though it is generally acceptable to reuse them.

Other things you need to consider is having hardened valve seats installed, valve guides, and replace the stock two-piece multi-groove valves with one-piece valves. Have the machinist machine the guides for the good seals and check the mating surfaces for straighteness and touch up if necessary.

Check your cylinder bores for taper and ridge. Worn cylinders and/or worn rings will allow more blow-by with the increased compression.

If the pistons are dished and not flat tops you will not realize the full benefits of the quench heads.
My Motor is still fresh less than 3000km since it was completely rebuilt so the bottom end stuff should be good. Block was decked and my open chamber heads also. Are the hardened valve seals a MUST? Since my motor is still complete I think I'll leave it alone for now and get these heads built properly before doing the swap. Or just offer them with the car if I ever sell it.

Thanks
All good recommendations by Don, in fact I followed his advise when I had my heads done. Concerning the harden valve seats, the machine shop said he didn't feel they were needed but I went ahead and had them done anyway.

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Valve recession with unleaded fuel is not a myth. I've had it happen on FE and Y block heads. The FE was much worse even though it wasn't driven much, it was a '70 engine.

So, yes I consider it a must, it was the first thing I did when I acquired my '71 Mustang.

 
Either way on the head bolts new or reuse be sure and run a tap in all the holes and blow them out good. DO NOT use assembly lube on the threads or Molycoat. Use what the mfg. of the bolts recommends if new and just light oil if the old ones. Assembly lube and Molycoat tend to over torque the bolts being slicker.

I have never had any fear of not having hard seats myself. Ran one Y block for for almost 100,000 miles and it never had anything but Pure White gas or unleaded in it. Just parked it in the barn never had the heads off. As far as the two piece valves breaking, don't float the valves and bend them and they won't break. Timing chain goes and you bump the valves and you don't change them then they are likely to rock and break head off. Huge valve spring pressure will also snap them but stock cam with stock springs won't be and issue.

If you are racing and running really narrow valve seats with triple angle valve job then the valves are going to beat in or recess down sooner also.

Most of us are not racing just going to shows and cruising around and no need to panic and try to squeeze 2 more HP out of the engine. I would love to sell you guys insurance. I don't even have homeowners.

Check the heads over, spring pressure, height, seats and guides, fix what is needed change the seals and enjoy your toy. Spending lots of money on racing stuff makes your engine not last as long as stock.

My opinion and I support this message, lol.

Been sanding drywall all day so I am grouchy.

 
Sometimes after adding up the cost of rebuilding heads say new harden seats and guides/stainless valves and so on, you paid for a new set alloy heads that flow and perform as good and better as factory iron. I seldom get new bolts unless there a reason, last dyno was a year ago was 389.6 hp to the tires at 6325 rpm's max torque 382.7 at 4580 rpms. So that puts it's about 448.0 at the flywheel. Not to bad for factory CC heads and a very mild street cam that's been driven twice across country to the left coast and back to PA. and other trips with 30 thousand miles total and 10 yrs now. Sometimes we just over think and over do what really need if we are on a tight budget. Butt that's just my opinion. Imagine what today's modern more advance alloy heads could do for a bit more money.... I guess I better shut up before somebody gets mad.....

 
Hi 83slimer, Looking at your top picture, do I see an "N" on the second right intake?, If so, what are the date codes located between the valve springs? If the date codes are 9 H 12 (69) or 0 B 13 (70) or something like that and if that is an N, you could have what is supposed to be 62.8cc heads from an early 70 engine that was supposed to be 11:1 compression ratio with factory pistons. See an earlier post of mine D0AE-N heads. At least, that is what we were led to believe I guess!!

As for valve stem seals, I had major issues with an umbrella style that were use on an earlier rebuild. This time around the engine shop used a type that has a 'spring' like nearly all oil seals have. I can't find the brand name, but I can find out and post tomorrow. Since switching to these seals, I have no more oil usage, job done!

Also, I chose to install KB 148 dish top pistons as 11:1 with flat tops was too much for my timing and 91 octane Shell. The KB148's gave me close to 10:1 and allowed perfect timing and NO detonation, although the engine does sound different!!

 
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Sometimes after adding up the cost of rebuilding heads say new harden seats and guides/stainless valves and so on, you paid for a new set alloy heads that flow and perform as good and better as factory iron. I seldom get new bolts unless there a reason, last dyno was a year ago was 389.6 hp to the tires at 6325 rpm's max torque 382.7 at 4580 rpms. So that puts it's about 448.0 at the flywheel. Not to bad for factory CC heads and a very mild street cam that's been driven twice across country to the left coast and back to PA. and other trips with 30 thousand miles total and 10 yrs now. Sometimes we just over think and over do what really need if we are on a tight budget. Butt that's just my opinion. Imagine what today's modern more advance alloy heads could do for a bit more money.... I guess I better shut up before somebody gets mad.....
Those are all good points, I spent more on the heads than I would have paid for a new set of alloy heads that would have no doubt been more bang for the dollar. I also spent more rebuilding my original Cleveland block than it would have cost me to get a new crate block. It all depends on where you want to go. I wanted to keep the original engine but I can perfectly understand someone just saying heck with it, I want a new crate engine which will be more reliable and powerful. Mines not for transportation, it's for nostalgic fun so I've tried to keep it original and time period correct as possible.

 
Sometimes after adding up the cost of rebuilding heads say new harden seats and guides/stainless valves and so on, you paid for a new set alloy heads that flow and perform as good and better as factory iron. I seldom get new bolts unless there a reason, last dyno was a year ago was 389.6 hp to the tires at 6325 rpm's max torque 382.7 at 4580 rpms. So that puts it's about 448.0 at the flywheel. Not to bad for factory CC heads and a very mild street cam that's been driven twice across country to the left coast and back to PA. and other trips with 30 thousand miles total and 10 yrs now. Sometimes we just over think and over do what really need if we are on a tight budget. Butt that's just my opinion. Imagine what today's modern more advance alloy heads could do for a bit more money.... I guess I better shut up before somebody gets mad.....
I'm with you on this one lol. I've already put a crap ton of money in this car at some point you have to ask yourself if the never ending black hole has a bottom!! Thanks for all the input guys. At this point I just want to get this car finished so I can finally drive it. At least I have the heads now and if I decide down the road to put them in I can. Been almost 8 years since I had my last ride in it. Picture is back when I first rebuilt the motor and put the harland sharp rockers in.

motor351.jpg

 
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Hi 83slimer, Looking at your top picture, do I see an "N" on the second right intake?, If so, what are the date codes located between the valve springs? If the date codes are 9 H 12 (69) or 0 B 13 (70) or something like that and if that is an N, you could have what is supposed to be 62.8cc heads from an early 70 engine that was supposed to be 11:1 compression ratio with factory pistons. See an earlier post of mine D0AE-N heads. At least, that is what we were led to believe I guess!!

As for valve stem seals, I had major issues with an umbrella style that were use on an earlier rebuild. This time around the engine shop used a type that has a 'spring' like nearly all oil seals have. I can't find the brand name, but I can find out and post tomorrow. Since switching to these seals, I have no more oil usage, job done!

Also, I chose to install KB 148 dish top pistons as 11:1 with flat tops was too much for my timing and 91 octane Shell. The KB148's gave me close to 10:1 and allowed perfect timing and NO detonation, although the engine does sound different!!
I did look up the date and they are october 1969 ( 9k28) and yes there is a N stamp. I ran 11 to 1 on my SBC with no issues as I always ran 93 octane had to get the timing just right or it would ping a little. I think the seals you mentioned are the type that came in the 302 gasket set i purchased for a 89 5.0 gt, had to push them on with a socket and they had a collar that grabs the collar around the head part of the stem. If you find a part number or brand let me know!

 
Hi 83slimer, Looking at your top picture, do I see an "N" on the second right intake?, If so, what are the date codes located between the valve springs? If the date codes are 9 H 12 (69) or 0 B 13 (70) or something like that and if that is an N, you could have what is supposed to be 62.8cc heads from an early 70 engine that was supposed to be 11:1 compression ratio with factory pistons. See an earlier post of mine D0AE-N heads. At least, that is what we were led to believe I guess!!

As for valve stem seals, I had major issues with an umbrella style that were use on an earlier rebuild. This time around the engine shop used a type that has a 'spring' like nearly all oil seals have. I can't find the brand name, but I can find out and post tomorrow. Since switching to these seals, I have no more oil usage, job done!

Also, I chose to install KB 148 dish top pistons as 11:1 with flat tops was too much for my timing and 91 octane Shell. The KB148's gave me close to 10:1 and allowed perfect timing and NO detonation, although the engine does sound different!!
I did look up the date and they are october 1969 ( 9k28) and yes there is a N stamp. I ran 11 to 1 on my SBC with no issues as I always ran 93 octane had to get the timing just right or it would ping a little. I think the seals you mentioned are the type that came in the 302 gasket set i purchased for a 89 5.0 gt, had to push them on with a socket and they had a collar that grabs the collar around the head part of the stem. If you find a part number or brand let me know!
The seals used on my engine were Pioneer OS1045. BUT there are several other suppliers of this style seal, Seal Power, Fel-Pro to name a couple. The seals you need will depend on the diameter and type of valve you use, so I guess you'll have to order them together. Check with your supplier!!

Also, the heads you have are not yet machined for studs. My "guy" tells me that is at least a $500 job considering that labour rates in Canada are likely higher than the US. On top of that, they should be checked for cracks. I have a set of GA heads that were checked and the bill was 130 bucks and they are still sitting on the shelf!! I also have a set of 69 "N" heads with studs that I may use on a block if I ever get enough spare cash to build an engine!!

Hope that helps you decide what to do, but I must admit, a new set of aluminum heads looks awful tempting at this point.

Geoff.

 
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Hi 83slimer, Looking at your top picture, do I see an "N" on the second right intake?, If so, what are the date codes located between the valve springs? If the date codes are 9 H 12 (69) or 0 B 13 (70) or something like that and if that is an N, you could have what is supposed to be 62.8cc heads from an early 70 engine that was supposed to be 11:1 compression ratio with factory pistons. See an earlier post of mine D0AE-N heads. At least, that is what we were led to believe I guess!!

As for valve stem seals, I had major issues with an umbrella style that were use on an earlier rebuild. This time around the engine shop used a type that has a 'spring' like nearly all oil seals have. I can't find the brand name, but I can find out and post tomorrow. Since switching to these seals, I have no more oil usage, job done!

Also, I chose to install KB 148 dish top pistons as 11:1 with flat tops was too much for my timing and 91 octane Shell. The KB148's gave me close to 10:1 and allowed perfect timing and NO detonation, although the engine does sound different!!
I did look up the date and they are october 1969 ( 9k28) and yes there is a N stamp. I ran 11 to 1 on my SBC with no issues as I always ran 93 octane had to get the timing just right or it would ping a little. I think the seals you mentioned are the type that came in the 302 gasket set i purchased for a 89 5.0 gt, had to push them on with a socket and they had a collar that grabs the collar around the head part of the stem. If you find a part number or brand let me know!
The seals used on my engine were Pioneer OS1045. BUT there are several other suppliers of this style seal, Seal Power, Fel-Pro to name a couple. The seals you need will depend on the diameter and type of valve you use, so I guess you'll have to order them together. Check with your supplier!!

Also, the heads you have are not yet machined for studs. My "guy" tells me that is at least a $500 job considering that labour rates in Canada are likely higher than the US. On top of that, they should be checked for cracks. I have a set of GA heads that were checked and the bill was 130 bucks and they are still sitting on the shelf!! I also have a set of 69 "N" heads with studs that I may use on a block if I ever get enough spare cash to build an engine!!

Hope that helps you decide what to do, but I must admit, a new set of aluminum heads looks awful tempting at this point.

Geoff.
The heads were supposedly checked at a machine shop but might get them looked at again. I already have the stud conversion on my open heads so I'd probably just swap them over to the cc heads. Thanks for the input.

 
I did look up the date and they are october 1969 ( 9k28) and yes there is a N stamp. I ran 11 to 1 on my SBC with no issues as I always ran 93 octane had to get the timing just right or it would ping a little. I think the seals you mentioned are the type that came in the 302 gasket set i purchased for a 89 5.0 gt, had to push them on with a socket and they had a collar that grabs the collar around the head part of the stem. If you find a part number or brand let me know!
The seals used on my engine were Pioneer OS1045. BUT there are several other suppliers of this style seal, Seal Power, Fel-Pro to name a couple. The seals you need will depend on the diameter and type of valve you use, so I guess you'll have to order them together. Check with your supplier!!

Also, the heads you have are not yet machined for studs. My "guy" tells me that is at least a $500 job considering that labour rates in Canada are likely higher than the US. On top of that, they should be checked for cracks. I have a set of GA heads that were checked and the bill was 130 bucks and they are still sitting on the shelf!! I also have a set of 69 "N" heads with studs that I may use on a block if I ever get enough spare cash to build an engine!!

Hope that helps you decide what to do, but I must admit, a new set of aluminum heads looks awful tempting at this point.

Geoff.
The heads were supposedly checked at a machine shop but might get them looked at again. I already have the stud conversion on my open heads so I'd probably just swap them over to the cc heads. Thanks for the input.
Unfortunately you can't just put those studs in your cc heads, assuming your rockers are on 7/16" studs. The pedestals need to be machined flat then they have to re-drill and tap the holes which are on a compound angle. Not that easy to do without proper knowledge. The studs in my spare set of heads are 7/16 x 20 on top and I think 7/16 x 14 on the bottom into the head, but these could be a special thread. I haven't checked that out to be honest, so please, nobody rag on me too much there!!.

Hope that helps and sheds some light on it. That is why it get expensive....quick.

 
Either way on the head bolts new or reuse be sure and run a tap in all the holes and blow them out good. DO NOT use assembly lube on the threads or Molycoat. Use what the mfg. of the bolts recommends if new and just light oil if the old ones. Assembly lube and Molycoat tend to over torque the bolts being slicker.

I have never had any fear of not having hard seats myself. Ran one Y block for for almost 100,000 miles and it never had anything but Pure White gas or unleaded in it. Just parked it in the barn never had the heads off. As far as the two piece valves breaking, don't float the valves and bend them and they won't break. Timing chain goes and you bump the valves and you don't change them then they are likely to rock and break head off. Huge valve spring pressure will also snap them but stock cam with stock springs won't be and issue.

If you are racing and running really narrow valve seats with triple angle valve job then the valves are going to beat in or recess down sooner also.

Most of us are not racing just going to shows and cruising around and no need to panic and try to squeeze 2 more HP out of the engine. I would love to sell you guys insurance. I don't even have homeowners.

Check the heads over, spring pressure, height, seats and guides, fix what is needed change the seals and enjoy your toy. Spending lots of money on racing stuff makes your engine not last as long as stock.

My opinion and I support this message, lol.

Been sanding drywall all day so I am grouchy.
I would have to disagree with the 2 piece valves never breaking. I never once floated mine, have a rev limiter set. And I wasn't running a huge cam that called for a ton a spring pressure either. I dropped a valve a destroyed a brand new motor. Very expensive lesson learned. Get rid of the stock valves.

As far as running the roller rockers, they do offer a kit that has the small threads on bottom and big threads on top for the roller rockers. With this kit there is no machining necessary on the pedestal. But like others have said I prefer to have the pedestals cut and tapped to accept the larger diameter studs for the roller rockers.

Heres a link to what a stock valve can do to your new motor! http://www.7173mustangs.com/thread-bad-day-catastrophic-engine-failure-updated-pics-of-the-carnage

Your motor looks a lot like mine used too!!

11ajvqp.png


 
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As far as running the roller rockers, they do offer a kit that has the small threads on bottom and big threads on top for the roller rockers. With this kit there is no machining necessary on the pedestal. But like others have said I prefer to have the pedestals cut and tapped to accept the larger diameter studs for the roller rockers.


Interesting! I certainly was not aware that there was a stud made with a smaller bottom diameter, 5/16th" I believe. It would indeed save a lot of work and money IF it was strong enough for job. I would think that set-up would be okay on an engine with a mild cam. I learn every day!

 
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