1966 Barracuda

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Glenn66

Glenn66

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Hello ALL !!
I have a 1966 Plymouth Barracuda. 273 V8. I am having work done on the vehicle and when they removed the heads (original), they found a crack in each of the heads. BOO !! I had replaced the intake with WEI 8022 Stealth intake manifold and running headers from Doug's Headers: Part # D450. Which all matched and fit perfectly. My question to you all out there is:
Where can I find a set of 273 heads for replacement and to rebuild? Will a set of 318 heads fit with what I am running? Or is there another reasonable option? I'm no gear head so I need layman's terms ... LOL..
Thank you ahead of time for all you help.

Glenn
 
You can look for original Mopar heads. Numbers that will work well are:178,234,920, and 675. Also the mid to late 80's #302 casting. Stay away from the 340-360 heads because the larger valves may come in contact with the small cylinders of the 273 .
 
toolmanmike said:
You can look for original Mopar heads. Numbers that will work well are:178,234,920, and 675. Also the mid to late 80's #302 casting. Stay away from the 340-360 heads because the larger valves may come in contact with the small cylinders of the 273 .
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Hey there Toolmanmike,
thanks for the response. Like I stated... im no gear head so when you say look at original mopar heads with those numbers you mentioned? what do the numbers mean and how do I look those up. My apologies... just not to savy on this stuff.

Thank you
 
Glenn66 said:
THANK YOU SO VERY MUCH
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So for example in looking at the casting numbers on that page:
2658920 – 1967, 318 LA-series small-block, 1.78/1.50 valves
A set of heads from a 318 with the cast 920 would be a match?
 
If you’d like a set from a 66, and you’re near Michigan, you can come by and get a set from one of these motors I’m going to junk.
 
Just an FYI- those newer style heads Mike talked about- 302 (last 3 digits of the part casting number) are available thru part houses rebuilt. What the application is I’m not sure but Summit Racing can help. Ask around here what they came on factory and you may find a set quicker than you think. Good luck!
 
Syleng1 said:
Just an FYI- those newer style heads Mike talked about- 302 (last 3 digits of the part casting number) are available thru part houses rebuilt. What the application is I’m not sure but Summit Racing can help. Ask around here what they came on factory and you may find a set quicker than you think. Good luck!
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Thank you I will contact Summit.
 
Rock Auto is usually who sells the remanufactured 302 heads. If you go on their website to look....use an 88 D100 Dodge pickup with a 318 as your vehicle. They have a $50 core charge per head, so if you don't have the same casting number heads to send back....you would have to eat the core charge! There are several members here that live in CA, and may be able to help if they see this thread. Good luck to you.
 
JDMopar said:
Rock Auto is usually who sells the remanufactured 302 heads. If you go on their website to look....use an 88 D100 Dodge pickup with a 318 as your vehicle. They have a $50 core charge per head, so if you don't have the same casting number heads to send back....you would have to eat the core charge! There are several members here that live in CA, and may be able to help if they see this thread. Good luck to you.
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Thank you JDMopar. Also I believe I have domed pistons they are not flat.
 
Glenn66 said:
Thank you JDMopar. Also I believe I have domed pistons they are not flat.
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They were replaced when the engine was being rebuilt. Will that matter as for the type of head or just make sure a thicker head gaskets are installed. I appreciate everyone's help and input very much. You all are great.
 
Hit me up, I got an old set on a 64 273 in the garage. Your new intake isn't going to fit though.....302's are the hot ticket. Small chamber, better chamber shape and the correct intake bolt angle/size. Just check valve seats for cracks. Any 318 head will work...
 
pishta said:
Hit me up, I got an old set on a 64 273 in the garage. Your new intake isn't going to fit though.....302's are the hot ticket. Small chamber, better chamber shape and the correct intake bolt angle/size. Just check valve seats for cracks. Any 318 head will work...
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Thank you Pishta I'll be calling Summit today.
 
The Commando pistons should work fine. They will have 2 valve reliefs, and the lower compression pistons will have 4 valve reliefs. Unless Cometic makes a really thin head gasket, .028 is the thinnest gasket I have seen advertised. The factory gaskets were thinner than that, I think? The intake you ordered will work perfect on the late model 302 heads, but you can easily make it work on 64-65 273 heads if the ones @pishta has are good. You can file the holes in the intake, and use wedge washers under the bolt heads. If you do end up buying a set of 302 heads from Rock Auto, you should still take them to a good machine shop and get them checked. You may need to get valve springs to match your cam, and get a good 3 angle valve job done before you put them on. Good luck with the build. :)
 
JDMopar said:
The Commando pistons should work fine. They will have 2 valve reliefs, and the lower compression pistons will have 4 valve reliefs. Unless Cometic makes a really thin head gasket, .028 is the thinnest gasket I have seen advertised. The factory gaskets were thinner than that, I think? The intake you ordered will work perfect on the late model 302 heads, but you can easily make it work on 64-65 273 heads if the ones @pishta has are good. You can file the holes in the intake, and use wedge washers under the bolt heads. If you do end up buying a set of 302 heads from Rock Auto, you should still take them to a good machine shop and get them checked. You may need to get valve springs to match your cam, and get a good 3 angle valve job done before you put them on. Good luck with the build. :)
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Thank you JD for the info. Much appreciated
 
one more note: the 302's are "closed" chamber heads (not fully round where the combustion chamber is) as well as the original 273 heads and the 273-4 pistons are +.0129 proud of the deck on a blueprinted motor. Never gonna happen but check your 4bbl piston to head clearance with your head gasket of choice. Most all the head gaskets sold today are at least .020 compressed thickness, some are up to .044 so this should not be an issue on a stock block. Decked blocks beware!
 
pishta said:
one more note: the 302's are "closed" chamber heads (not fully round where the combustion chamber is) as well as the original 273 heads and the 273-4 pistons are +.0129 proud of the deck on a blueprinted motor. Never gonna happen but check your 4bbl piston to head clearance with your head gasket of choice. Most all the head gaskets sold today are at least .020 compressed thickness, some are up to .044 so this should not be an issue on a stock block. Decked blocks beware!
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THANK YOU FOR ALL THE INFO!! GREAT STUFF!.
 
Not to slander pishta, but, I wouldn't use 315 heads. They're even more crack prone than the 920's and you have to do the mods to the intake to get them to work. There are much better heads out there. Keep in mind that if you change to another casting number, you may change the compression ratio. In some cases, drastically. Also, the later smog port heads will need to have plugs installed in those ports. or you will have exhaust leaks. You say you have headers, so, there should be no exhaust interference that stock manifolds have on smog heads. Should you change back to stock manifolds, you'll need to grind part of the head casting on the driver's side or you will break ears off the manifold.
 
cudamark said:
Not to slander pishta, but, I wouldn't use 315 heads. They're even more crack prone than the 920's and you have to do the mods to the intake to get them to work. There are much better heads out there. Keep in mind that if you change to another casting number, you may change the compression ratio. In some cases, drastically. Also, the later smog port heads will need to have plugs installed in those ports. or you will have exhaust leaks. You say you have headers, so, there should be no exhaust interference that stock manifolds have on smog heads. Should you change back to stock manifolds, you'll need to grind part of the head casting on the driver's side or you will break ears off the manifold.
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Thank you
 
Any pictures of the cracks? I find it a bit unusual for both heads to be cracked. I've disassembled a few 273 motors and have never seen a cracked head. Where are the cracks? Just sayin...
 
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