are these heads not usable?
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Joined: Nov 2002
Posts: 1,072
are these heads not usable?
I posted this in the lt1 section, but i think it fits here better since its a bit of a more 'advanced' question... so im pasting it here
http://img92.exs.cx/img92/3972/hpim03294wh.jpg
http://img92.exs.cx/img92/5707/hpim03275rl.jpg
http://img184.exs.cx/img184/9872/hpim03287xd.jpg
the far right cc....
One engine builder told me that is not acceptable, and these heads are garbage... the 1st thing when he said these heads were was 'these heads arent smooth, they need to be resurfaced' well the drag motor builder told me this is perfectly fine, and looks level, u dont want it to be smooth, but u want it to be level... u want some sort of RA on it, so that it bites into the gasket... also he told me the coolant lines (at the bottom area) well were welded, and thats not good either... also told me the cc wall spacing is too narrow, and it will leak....
there also seems to be what seems like 'tinnnnyyyy nicks' on the head surface area, and my engine builder told me they will create hot spots, then i took it to a drag motor builder, and he told me those marks can create detonation, but he can work on them, and the nicks will not create hotspots, but they would if they were bumps instead....
what do you think?
http://img92.exs.cx/img92/3972/hpim03294wh.jpg
http://img92.exs.cx/img92/5707/hpim03275rl.jpg
http://img184.exs.cx/img184/9872/hpim03287xd.jpg
the far right cc....
One engine builder told me that is not acceptable, and these heads are garbage... the 1st thing when he said these heads were was 'these heads arent smooth, they need to be resurfaced' well the drag motor builder told me this is perfectly fine, and looks level, u dont want it to be smooth, but u want it to be level... u want some sort of RA on it, so that it bites into the gasket... also he told me the coolant lines (at the bottom area) well were welded, and thats not good either... also told me the cc wall spacing is too narrow, and it will leak....
there also seems to be what seems like 'tinnnnyyyy nicks' on the head surface area, and my engine builder told me they will create hot spots, then i took it to a drag motor builder, and he told me those marks can create detonation, but he can work on them, and the nicks will not create hotspots, but they would if they were bumps instead....
what do you think?
Registered User
Joined: Jun 2002
Posts: 888
From: Langley, BC,Canada
Re: are these heads not usable?
Lay the head gaskets you're going to use on top of it and see if the damage reaches the gasket. If the gasket overlaps it they are no good. As for the little nicks if you carefully smooth them out they shouldn't produce hotspots. Again this is as long as they are not on a gasket sealing area.
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Joined: Aug 2000
Posts: 4,305
From: North Vancouver, BC
Re: are these heads not usable?
like I said on the LT1 tech post you made "looks like one of those cc's touches the gasket area" but as long its not horrible, those 1074 gaskets look pretty soft around the ring, I'd still give it a shot.
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Joined: Oct 2002
Posts: 6,518
Re: are these heads not usable?
They are not going to send the heads to the trash that's for sure....
They could be run, but they will cause hot spots. If you are not pushing the compression, or dynamic compression I don't know if I would get my panties in a bunch about these things.
The last picture is the best one of what the damage is there.
Now if you want to fix it......
Find a good aluminum welder, have him fill the pock marks and build up the area so it's higher than the surface (because there will be a slight indent where the weld goes so you'll have more welded than you think). He should use a TIG and 5356 Al rod to do this properly.
Then you want to take the heads home and throw them in the oven at about 285degs for 2 hours. Get the head to that temp hold for two hours, and just turn the oven off and let it cool. Don't open the door. This will stress relieve the head after the welding, it's not going to put tons of heat in the head but it's a good safety factor.
Then have the head decked to get a good surface and the heads will be like new. It takes more work to make them perfect but that will get them there. You might have to do a little chamber work when it's all said and done but it's not a huge deal.
Bret
They could be run, but they will cause hot spots. If you are not pushing the compression, or dynamic compression I don't know if I would get my panties in a bunch about these things.
The last picture is the best one of what the damage is there.
Now if you want to fix it......
Find a good aluminum welder, have him fill the pock marks and build up the area so it's higher than the surface (because there will be a slight indent where the weld goes so you'll have more welded than you think). He should use a TIG and 5356 Al rod to do this properly.
Then you want to take the heads home and throw them in the oven at about 285degs for 2 hours. Get the head to that temp hold for two hours, and just turn the oven off and let it cool. Don't open the door. This will stress relieve the head after the welding, it's not going to put tons of heat in the head but it's a good safety factor.
Then have the head decked to get a good surface and the heads will be like new. It takes more work to make them perfect but that will get them there. You might have to do a little chamber work when it's all said and done but it's not a huge deal.
Bret
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Joined: Nov 2002
Posts: 1,072
Re: are these heads not usable?
ok here is what the head shop said when i took it to them to have a look at it...
1. too much welding, tempers the head
2. springs are rusty, they will break
3. resurfaced on belt sander and alot was taken, gunna raise compression alot, and might need to 'fit' the intake on, cuz the heads are so low now, they should have been milled, belt sander is caveman stuff he said
4.spring seats arent correctly located on the guide, gunna wear out the seals
5. resurfaced way too much, and it still needs resurfacing since it was done on a belt sander
6. too much welding on the head already
7.did i mention too much welding?
1. too much welding, tempers the head
2. springs are rusty, they will break
3. resurfaced on belt sander and alot was taken, gunna raise compression alot, and might need to 'fit' the intake on, cuz the heads are so low now, they should have been milled, belt sander is caveman stuff he said
4.spring seats arent correctly located on the guide, gunna wear out the seals
5. resurfaced way too much, and it still needs resurfacing since it was done on a belt sander
6. too much welding on the head already
7.did i mention too much welding?
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Joined: Mar 2000
Posts: 2,037
From: 51°N 114°W, 3500' elevation
Re: are these heads not usable?
You should have seen one of my heads after I dropped a valve. Combusion chamber got chewed up real bad but didn't punch a hole through the casting. New valves and seats and a little bit of cleaning them up and I bolted them back on with no problems. When I was done, they still looked worse than those heads.
As long as they pressure test and the damage doesn't pass through the gasket as mentioned above, I'd use them. Just get them resurfaced enough to make sure it's square.
1: So? The head goes through a lot of heat cycles just operating.
2: Get new springs. A little bit of surface rust isn't great but they won't break. Once the engine runs, they'll be covered in oil anyway.
3: Someone surfaced them with a belt sander?? They'll really need to be resurfaced. They could also be angle milled to help get the intake lined up again.
4: Install spring locators
5: Depends on the deck thickness. If it gets too thin then there's not much else that can be done. Production heads are not very thick to begin with. Aftermarket heads usually have a thick deck surface.
6: So?
7: So again?
As long as they pressure test and the damage doesn't pass through the gasket as mentioned above, I'd use them. Just get them resurfaced enough to make sure it's square.
1: So? The head goes through a lot of heat cycles just operating.
2: Get new springs. A little bit of surface rust isn't great but they won't break. Once the engine runs, they'll be covered in oil anyway.
3: Someone surfaced them with a belt sander?? They'll really need to be resurfaced. They could also be angle milled to help get the intake lined up again.
4: Install spring locators
5: Depends on the deck thickness. If it gets too thin then there's not much else that can be done. Production heads are not very thick to begin with. Aftermarket heads usually have a thick deck surface.
6: So?
7: So again?
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Joined: Oct 2002
Posts: 6,518
Re: are these heads not usable?
Originally Posted by Seal
ok here is what the head shop said when i took it to them to have a look at it...
1. too much welding, tempers the head
2. springs are rusty, they will break
3. resurfaced on belt sander and alot was taken, gunna raise compression alot, and might need to 'fit' the intake on, cuz the heads are so low now, they should have been milled, belt sander is caveman stuff he said
4.spring seats arent correctly located on the guide, gunna wear out the seals
5. resurfaced way too much, and it still needs resurfacing since it was done on a belt sander
6. too much welding on the head already
7.did i mention too much welding?
1. too much welding, tempers the head
2. springs are rusty, they will break
3. resurfaced on belt sander and alot was taken, gunna raise compression alot, and might need to 'fit' the intake on, cuz the heads are so low now, they should have been milled, belt sander is caveman stuff he said
4.spring seats arent correctly located on the guide, gunna wear out the seals
5. resurfaced way too much, and it still needs resurfacing since it was done on a belt sander
6. too much welding on the head already
7.did i mention too much welding?
"Then you want to take the heads home and throw them in the oven at about 285degs for 2 hours. Get the head to that temp hold for two hours, and just turn the oven off and let it cool. Don't open the door. This will stress relieve the head after the welding, it's not going to put tons of heat in the head but it's a good safety factor."
That will take care of it..... You can either do that or hit it with a blunt air chisel, but I like the heating idea to stress relieve the head.
This is not some cave man trick, it works. Learned this thru heat treaters and some very good engine builders.
Bret
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Joined: Oct 1999
Posts: 356
From: Oakland City, IN
Re: are these heads not usable?
It looks like they were cut down like .015-.025 or so. I suspect that someone was trying to build up a very high compression drag motor (with the welding up of the lower coolant passeges, maybe an alcohol motor?). Why they would choose to put this effort into an LT1 head is anybody's guess, but these heads are far from "trash".
As far as the valve springs go though, if you can't have them tested (seat and open pressures) then I wouldn't run them anyway. I subscribe to the first rule of engine building, which is to trust NO ONE. Get some new springs and seats, have these resurfaced JUST enough to make them smooth (shouldn't be more than a couple thou) and clean up those chambers, and run the bejeezuz out of 'em. I've seen a LOT worse looking stuff go another round.
OBTW, one thing you're gonna have to check if you DO run these is your pushrod length.
Dave C.
As far as the valve springs go though, if you can't have them tested (seat and open pressures) then I wouldn't run them anyway. I subscribe to the first rule of engine building, which is to trust NO ONE. Get some new springs and seats, have these resurfaced JUST enough to make them smooth (shouldn't be more than a couple thou) and clean up those chambers, and run the bejeezuz out of 'em. I've seen a LOT worse looking stuff go another round.
OBTW, one thing you're gonna have to check if you DO run these is your pushrod length.
Dave C.
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Joined: Jul 2000
Posts: 520
From: MD
Re: are these heads not usable?
Real world there isn’t a good reason to worry about heat treat/temper when you weld up those divots. When you weld them the cold head will self quench the areas that you weld and you’ll locally anneal the aluminum (make it soft). Let them sit a little bit (Aluminum tempers just sitting, faster if you try to work it or give it a little bit of heat) or the first time the engine goes through a heat/cool cycle and they will temper evening out the whole head anyway.
If it was me, and I was really worried about he integrity of the whole head and thickness of some spots I’d take and throw the whole thing in the oven at between 250 and 400*F (probably if it was me I’d get it up to around 400* giving me more time to work) and then weld all the divots shut with either a MIG or TIG (probably a MIG equipped for welding aluminum would be best, it’s faster and will put less heat into the base metal), then cover them up and let them cool as slowely as possible (throw them back in the oven, cover them with a pile of welding gloves/welding blanket and then some towels or even burry them in a big pile of kitty litter, whatever to get them to hold some heat for a while and to cool slowly and evenly). That will take care of any temper issues that anyone might think that they have, but more importantly, it will put less localized stress on the head making it less likey that your welding will cause any warping or cracking, even if you have to do a lot of it.
After that get it decked flat, grind any remaining welds protruding into the chambers… and it will be as good as new, or at least as good as a new slightly excessively decked head.
If it was me, and I was really worried about he integrity of the whole head and thickness of some spots I’d take and throw the whole thing in the oven at between 250 and 400*F (probably if it was me I’d get it up to around 400* giving me more time to work) and then weld all the divots shut with either a MIG or TIG (probably a MIG equipped for welding aluminum would be best, it’s faster and will put less heat into the base metal), then cover them up and let them cool as slowely as possible (throw them back in the oven, cover them with a pile of welding gloves/welding blanket and then some towels or even burry them in a big pile of kitty litter, whatever to get them to hold some heat for a while and to cool slowly and evenly). That will take care of any temper issues that anyone might think that they have, but more importantly, it will put less localized stress on the head making it less likey that your welding will cause any warping or cracking, even if you have to do a lot of it.
After that get it decked flat, grind any remaining welds protruding into the chambers… and it will be as good as new, or at least as good as a new slightly excessively decked head.
Last edited by WS6 TA; Jan 25, 2005 at 12:22 PM.
Thread Starter
Registered User
Joined: Nov 2002
Posts: 1,072
Re: are these heads not usable?
see guys, the main problem is that these heads were decked too much for my use (a turbo motor where i need low compression) and they need to be resurfaced AGAIN....
the guy said it has been resurfaced to much that my intake might not even fit right cuz the heads are so low... and with so much decking, and my 560 lift cam, and these big valves which sit 50 over they might hit my pistons...
the guy said it has been resurfaced to much that my intake might not even fit right cuz the heads are so low... and with so much decking, and my 560 lift cam, and these big valves which sit 50 over they might hit my pistons...
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Joined: Aug 2001
Posts: 222
Re: are these heads not usable?
Originally Posted by WS6 TA
Real world there isn’t a good reason to worry about heat treat/temper when you weld up those divots. When you weld them the cold head will self quench the areas that you weld and you’ll locally anneal the aluminum (make it soft). Let them sit a little bit (Aluminum tempers just sitting, faster if you try to work it or give it a little bit of heat) or the first time the engine goes through a heat/cool cycle and they will temper evening out the whole head anyway.
If it was me, and I was really worried about he integrity of the whole head and thickness of some spots I’d take and throw the whole thing in the oven at between 250 and 400*F (probably if it was me I’d get it up to around 400* giving me more time to work) and then weld all the divots shut with either a MIG or TIG (probably a MIG equipped for welding aluminum would be best, it’s faster and will put less heat into the base metal), then cover them up and let them cool as slowely as possible (throw them back in the oven, cover them with a pile of welding gloves/welding blanket and then some towels or even burry them in a big pile of kitty litter, whatever to get them to hold some heat for a while and to cool slowly and evenly). That will take care of any temper issues that anyone might think that they have, but more importantly, it will put less localized stress on the head making it less likey that your welding will cause any warping or cracking, even if you have to do a lot of it.
After that get it decked flat, grind any remaining welds protruding into the chambers… and it will be as good as new, or at least as good as a new slightly excessively decked head.
If it was me, and I was really worried about he integrity of the whole head and thickness of some spots I’d take and throw the whole thing in the oven at between 250 and 400*F (probably if it was me I’d get it up to around 400* giving me more time to work) and then weld all the divots shut with either a MIG or TIG (probably a MIG equipped for welding aluminum would be best, it’s faster and will put less heat into the base metal), then cover them up and let them cool as slowely as possible (throw them back in the oven, cover them with a pile of welding gloves/welding blanket and then some towels or even burry them in a big pile of kitty litter, whatever to get them to hold some heat for a while and to cool slowly and evenly). That will take care of any temper issues that anyone might think that they have, but more importantly, it will put less localized stress on the head making it less likey that your welding will cause any warping or cracking, even if you have to do a lot of it.
After that get it decked flat, grind any remaining welds protruding into the chambers… and it will be as good as new, or at least as good as a new slightly excessively decked head.
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Joined: Oct 2002
Posts: 6,518
Re: are these heads not usable?
Gettin heat in the head is part of it..... Most guys who weld up a full chamber and start over with a new chamber design really need this. Now the problem is it's going to take you about 45-60mins a chamber so that head is going to get tons of heat in it, and most guys use a 3/32nd TIG and have to throw helium at it and a special coated tungsten tip so you keep the tip cold enough not to melt. If your not screwing around you use a 3/16 tip and a big TIG to get the job done.
A MIG might help when you are doing a whole cylinder but doing what he needs probably needs to be done with a TIG since it's just small little spots.
BTW anyone who has welded up a full chamberin a head to this point would understand stress relieving the head. It's close to what WS6 TA said but the specs on that are specific, this is straight from one of the biggest heat treaters in the NE. The slower the cool the better that's a good point. If you don't stress relieve the head you are going to be chasing the **** out of it with the cutter on the decking machine since it will be so warped it's funny.
Bret
A MIG might help when you are doing a whole cylinder but doing what he needs probably needs to be done with a TIG since it's just small little spots.
BTW anyone who has welded up a full chamberin a head to this point would understand stress relieving the head. It's close to what WS6 TA said but the specs on that are specific, this is straight from one of the biggest heat treaters in the NE. The slower the cool the better that's a good point. If you don't stress relieve the head you are going to be chasing the **** out of it with the cutter on the decking machine since it will be so warped it's funny.
Bret