1981 Canadian EL vs 1981 US EK Heads (PICTURES!)

[2ndGenGuy]

Okay everybody, this is what you've all been waiting for! I got my Canadian EL head back from the shop. Boy is she purdy. Clean enough to eat off of. Here's the pics side by side of the original head from my 1981 US Accord with the EK1, vs the head I picked up from Mike (guyhatesmycar) up in Canada off of his EL engine.

The clean one is the Canadian head. The dirty one is the American one.
Please note that these are both 1981 model year heads.
The Canadian one has no CVCC, and is from a 1602 EL block.
The American one does have CVCC, and is from a 1751 EK1 block.

I have no idea what the earlier American EL heads with CVCC looked like. I'm sure they looked like a combination of these two heads.

This will probably make sense as to why the 1602 Canadian cars put out the same horsepower as the 1751 US cars.



Note the different port layout. Exhaust ports are on top in this picture (because the head is upside down). The exhaust ports are more evenly spaced. I believe that this flows better in through the exhaust system. Also notice that the ports on the EL head are quite a bit bigger, but it may be hard to tell by looking at these pictures. Just trust me on this one.



Here's the combustion chambers. Big difference here being the lack of CVCC auxillary valve. Notice on the Canadian head, the spark plug goes directly into the combustion chamber, instead of into the pre-chamber.



The spark plug holes had to be cast differently. Obviously this is due to the relocation of the spark plug tip, from the pre-chamber on the US head to the combustion chamber on the Canadian head.



Here's the distributor side. Looks pretty much the same on both heads. Distributor, thermostat and housings are interchangable.



This side is pretty much identical. Different cam gears were used. The Canadian head has a cam gear that looks suspiscously like the one on the '95 Civic that I replaced the head gasket on... Hmm, might an adjustable cam gear for the D16 work for this?



Here's a top down view. Quite similar in design of the head itself. But note again, the lack of CVCC aux valves and rockers. Also the cam only needs 8 lobes on the Canadian head instead of 12, so I think this also makes it more durable.



Here's another view of the CVCC valve area. Just for more reference.

Again, a big thanks to guyhatesmycar for just GIVING me this cylinder head. Sure made this project loads more fun, and should give me a little performance bump.

[Hash_man_Se_i]

Thats pretty cool... I learned something today.

Good luck with your build

[79cord]

Wow, your EL head must virtually be '82 spec. What was its build date?
I think you've gone a step newer between your EK & EL heads!
My Accord & Prelude EL heads, brought into Aust. in Sept. '79, Dec '79, Dec '80 are all more like your EK casting but without the CVCC valves/rockers etc. with intake ports outermost, & exhausts below!
I thought that was a 2nd gen change -intake & exhaust valves swapping places...along with revisions to water/oil gallery paths from head to block.
Obviously Honda was very busy making revisions during this period...& the evolution from 1st to 2nd gen engines more progressive.
I thought most of the model year changes occured around October...& my Dec. '80 Prelude has the revised floor & g/shift like the '81's too....

[Cheeseburger]

dam sweet!!!!

[offthahook]

Like whoa. That head looks sweet! I assume you're putting a new timing belt and water pump on too. That dual spade connector even looks yummy. I wanna say is what kicks the fans on, but I'm not sure. The whole thing looks freaking good. The block will look so good after it's all cleaned up too. Pretty much, the thing will shine. I had never seen a Canadian head up close like that. That's cool to see them side by side. Hold onto the old head for sure! Just think where that head was a couple months ago and how you resurrected it. nice.

[2ndGenGuy]

Wow, your EL head must virtually be '82 spec. What was its build date?
I think you've gone a step newer between your EK & EL heads!
My Accord & Prelude EL heads, brought into Aust. in Sept. '79, Dec '79, Dec '80 are all more like your EK casting but without the CVCC valves/rockers etc. with intake ports outermost, & exhausts below!
I thought that was a 2nd gen change -intake & exhaust valves swapping places...along with revisions to water/oil gallery paths from head to block.
Obviously Honda was very busy making revisions during this period...& the evolution from 1st to 2nd gen engines more progressive.
I thought most of the model year changes occured around October...& my Dec. '80 Prelude has the revised floor & g/shift like the '81's too....

How can I tell the dates on the head? From the original car you mean?

[Ichiban]

Sorry to break this to you John, but that is a 1983 EL1602 head. The engine originally came out of my parent's 83 sedan, got swapped into my 83 hatch, drove across the country and back, came out, sat, went into the 81 and blew up.

It should give you a nice compression boost, a better burn and more flow. We should build some shorty 4-1 headers for it. What are you gonna use for carb/intake?

[79cord]

But are the two heads interchangeable -assuming you also have the different intake/exhaust manifolds. I've heard too many claims that they weren't due to "oil & coolant path revisions" with matching different head gaskets -though these certainly look virtually the same. I've also heard that the revised intake/exhaust positions were applied during '81.
And that most of the compression ratio raise between 1st & 2nd gen EL engines was more domed Pistons?
What a headache.

[offthahook]

Man the year to year changes are still killing me! I would say if there is ANY doubt, you should get the intake and exhaust manifolds from guyhatesmycar (or some other Canadian Accord) and see how they line up. A little revision in any oil or coolant passage between the heads and you're in trouble. You could build your engine and test it out of the car to see how she goes. Probably a little bit of a headache, but it would be some peace of mind. I don't even know if the intake and exhaust manifolds would work in your 1G Accord. Aren't you glad you still have your original head just in case something happens with this swap? I'm not sure we have too many people who have ever tried this swap that looks like it would "work on paper."

I would look for any and all casting numbers and letters and maybe call your local Honda dealer. They probably won't have the answer, but they can call tech. support and check for you and verify the date code. Man you are learning on this project. Where are all the old Honda engineers??? Not that they could even tell us what would work or not. As thorough as John has been, I think he'll get it right, not just close enough. A machine shop may have date code markings books, but I don't know if they will have the old Honda stuff. Keep us posted; this is so interesting.

[2ndGenGuy]

Sorry to break this to you John, but that is a 1983 EL1602 head. The engine originally came out of my parent's 83 sedan, got swapped into my 83 hatch, drove across the country and back, came out, sat, went into the 81 and blew up.
It should give you a nice compression boost, a better burn and more flow. We should build some shorty 4-1 headers for it. What are you gonna use for carb/intake?

Oooh snap. I didn't realize it was from 1983. Bah well. Its a better head either way. I hope that 79Cord is wrong and that this head will go on with no problem. The oil and coolant passages look the same so far, but I guess I should match my old head gasket up to be sure. I think I remember you telling me now that it's from an '83. The bolt patterns look the same. Now I gotta figure out how to get that intake / exhaust gasket.

Well the good news is that the '83's probably had the best head in the true Honda E-series engines. The ES2, I kinda don't consider an e-series engine, more like an A-series than anything.

For the carb / intake, I'm going to use the stock manifold, and find a Weber adapter plate that will work on it. Then I'll take the 32/36 from my Sedan and pop it on. Or I'll buy a used 32/36 and run with it for a while, until I get the 84 torn apart ready for it's new engine / brakes / interior / suspension / paint.

[2ndGenGuy]

Man the year to year changes are still killing me! I would say if there is ANY doubt, you should get the intake and exhaust manifolds from guyhatesmycar (or some other Canadian Accord) and see how they line up. A little revision in any oil or coolant passage between the heads and you're in trouble. You could build your engine and test it out of the car to see how she goes. Probably a little bit of a headache, but it would be some peace of mind. I don't even know if the intake and exhaust manifolds would work in your 1G Accord. Aren't you glad you still have your original head just in case something happens with this swap? I'm not sure we have too many people who have ever tried this swap that looks like it would "work on paper."

I would look for any and all casting numbers and letters and maybe call your local Honda dealer. They probably won't have the answer, but they can call tech. support and check for you and verify the date code. Man you are learning on this project. Where are all the old Honda engineers??? Not that they could even tell us what would work or not. As thorough as John has been, I think he'll get it right, not just close enough. A machine shop may have date code markings books, but I don't know if they will have the old Honda stuff. Keep us posted; this is so interesting.

I would love to test it outside the car, I just don't know how I could do it. I'd need a hefty stand to keep the engine from spinning itself through the garage wall. Then I'd need a fuel pump, and +12v, and all kinds of mess. I think it would be easier to try it out in the car, and swap the head in the car as well. It's a pretty painless job, especially when you've got an aftermarket carb.

Luckily, Mike and I were thinking enough that early morning to get the exhaust and intake manifolds too. You shoulda seen the US Customs people all confused why I would drive so far for some old used Honda parts. The just don't understand.

All they asked me was "You bringing back any Marijuana, son? Any drugs???" All I wanted to say was "Dude, I live in fucking Olympia, meth house capitol of the world, and home of Evergreen State College, the MOST STONED COLLEGE ON THE PLANET. The state forest 10 minutes away has more Marijuana plantations than you ever new existed! If I wanted drugs, I woudln't need to drive 9 hours." But I didn't. And he proceeded to search my car.

[Ichiban]

Uh, hey, In the picture the bottom row (manfold side) of bolt holes looks sorta different between the two heads?

[79cord]

Looks like they might have moved a little & added another two outboard a little closer to the centerline - I hope something can be machined to reconnect?
Pain.
Might have to rename this whole thread 81-83 conversion!

[2ndGenGuy]

Shit. Now I have to go out and look at them. I thought I checked all that though...

Holy fucking shit. Not only does that middle one not line up. Neither does the top and bottom bolts on that same side. The fucked part is that they're only about 2mm off. Why oh god why didn't I think to match up the head gasket on this before hand... I thought that I did though... What the fuck... All the oil and water passages line up just fine, maybe thats all that I was looking at... Fucking Honda.

[79cord]

Sorry to hear the anguish.
So you get a 2g block or clean up the old head.
My last experiance of it was finding the different flywheel to crankshaft bolt sizes during 1980 doing the Manual/Auto swap on my Prelude leading me to discover the '81 G/shift linkage revisions. No external differences & registered the same year but all I got off the parts car I bought for the conversion was the pedal box & hydraulic clutch! -Floor, g/shift linkage, g/box & flywheel were different !
Then there was the different rr 1/4 & fuel door between '78-9 Accord, & the different rear suspension arm, & the.....

[offthahook]

Man, I was afraid of this. Honda always seems to make it just a little bit off so you can't easily swap stuff out. I've run into these "slight differences" quite a few times. Could you use the intake and exhaust manifolds form the Canadian model with the US block? I'm trying to remember if that would work or not. CVCC and non CVCC... can they coexist? If push comes to shove, at least you have the original head. Hope that doesn't happen, but we're in uncharted territory here. Damnit.

[2ndGenGuy]

Yeah I'm bummed. I'm wondering if I can't have the holes machined to work. I bet that if somebody did it though, the holes would go right through into the exhaust or intake ports. Or maybe there's enough clearance. You would think that without the CVCC stuff that there would be more room for things.

Funny, this also means that they changed the block too. Just enough to screw you again. Damnit, I wish I would have checked beforehand. Lesson learned.

[offthahook]

Yeah I'm bummed. I'm wondering if I can't have the holes machined to work. I bet that if somebody did it though, the holes would go right through into the exhaust or intake ports. Or maybe there's enough clearance. You would think that without the CVCC stuff that there would be more room for things.

Funny, this also means that they changed the block too. Just enough to screw you again. Damnit, I wish I would have checked beforehand. Lesson learned.

Beware. This is where Hondas do not fare well with modding of any kind. It's possible a good machinist could do something like this, but Honda tolerances are usually VERY VERY narrow on all components. That's why kids modding their Civics always run into trouble. When I rebuilt my 78 Accord in 1989 it was hard. Just finding anyone familiar with a Honda was hard, much less an engine block assembly. The year to year changes killed me then-- 1976-1981 Accords were not all the same as I found out. That's why it is a huge sense of accomplishment to modify anything Honda (not mufflers and CAI type stuff), especially the old stuff. You'll hit snags like this and the answer is just not out there because no one has done it.

I guess you could try to get a Canadian head from an 81 or go get the block from the car where your head is from. Did that engine blow so hard that the block is unusable? I know, it's a lot more time and effort though. I guess nothing worth having comes easily! At this point, I would not try to mod. that fresh head to "make it work". I would also look into getting the stock EK 1751 head worked over. Man, maybe my "stock OEM" mentaility is a good thing. I think you're still on target to getting that non CVCC motor in your 1G, but it may take longer. Don't blame Honda; they never intended their products to be swapped and they do not like their products to be swapped. They think ahead too much sometimes.

[79cord]

I doubt you'd have any problems with a US 2nd gen EK block. The two engines were allways closely related & Honda.co.jp lists a 1602 CVCC engine which would have had to have been a hybrid.

[offthahook]

I doubt you'd have any problems with a US 2nd gen EK block. The two engines were allways closely related & Honda.co.jp lists a 1602 CVCC engine which would have had to have been a hybrid.

Probably true, but we are finding that "close" isn't always doable. It's like Honda just varies different markets with slight variations that seem trivial, but are just enough to make it not really doable. This old stuff changes minute to minute it seems! Trial and error is the only way to know fore sure I suppose.

[Ichiban]

John, slap the head gasket (that fits the block) onto the deck of the head. If push comes to shove, ship the head back to me and I'll relocate the holes and fix the counterbores so the bolt heads still fit. May want to run a washer over the tops of the holes though. It's just the bottom edge and center holes right? The rest still line up?

Mike

Edit: Looking at the pictures it seems like the bottom edge, center and edge holes. As it looks like, they need to be relocated straight up towards the center of the head approx 3mm, I can't see it interfering with the ports at all, just possibly the water jacket on the center hole. I was thinking if there is port or passage interference, I could ream the holes oversize and install a pressed in sleeve to keep out the coolant/exhaust/intake mixture etc.