[scortster]

The guide to first generation (U.S.) Escort/Exp, Lynx/Ln7 cylinder heads:

Intro:
Hello everyone, my name is Sean. Before I begin, let me start off this write-up with a guarantee, and a disclaimer. First off I guarantee that the information in this guide is to the best of my knowledge 100% accurate. All of my resorces are of first hand account. I have spent countless hours for the past year and a half, looking over nearlly 200 heads in junk yards, parts suppliers, and machine shops. There is no hear-say or speculation. So if I did not see it, I did not write it. As for my disclaimer, All I can say is I'm only human and we can all make mistakes. Please!!! If you catch any mistakes or have something you would like to address, feel free to let me know, but I do ask that it be handled in a somewhat professional manner though. I'm not interested in starting any arguments.

Goal:
My goal is to impower the facts, and lay to rest the speculation by starting a permenent collection of information about the 1st gen (1981-1990) heads. My personal focus has been on the uncommon, little known, and unique facts about the heads. I'm not going to just retype every measurment, clearance, and spec that can be found in any service manual. I want to collect info that woun't be found in books like, port shape and size, casting #'s, plant codes, ect.

Help:
If anyone has any additial information or write-ups to share, they are more than welcome and encouage to do so. I'm looking for all the info I can get for this page, so if you have a head sitting around please send me any info you can. (in a PM preferablly).

Genral info:
Some basics on the CVH heads; The abbreviation CVH stands for Compound Valve-angle Hemisphereical chamber head. No wonder it's abbreviated. The CVH engine came in two displacements in the US 1st gens, a 1.6L, and 1.9L. A 1.3L is mentioned in some service manuals, but was never used in the US. There are three different combustion chamber designs; the first is the HEMI, it has a round dome shaped (hemisphrical) chamber. The second is the High Swirl Combustion or HSC, it uses a heart-shaped chamber. Finally the Third is the Lean Burn, or Semi Hemi. and it has a D-shaped dome chamber.

Some more specific aspects;
The CVH heads were cast in six different years: 1981, 83', 85', 87', 88', and 90' in a number of different casting plants. All 1.6L CVH heads are HEMI chamber heads. Also all 1.6L heads have larger exhaust ports than the 1.9L. I know that it has been said many times it the past that only the heads on the turbocharged cars have the large exh. ports, but it's just not true. Actually there is nothing special or different at all about the heads that got put on the turbo cars. All of the 1.9L heads use the smaller exh. ports. Both The HEMI, and The HSC heads use round intake ports. The Lean burn heads use oval ports. All of the HEMI heads share one size intake valve and the one size exhaust valve. The int & exh. valves on the Lean burn and HSC heads are alittle smaller. Also it's a bit insigniffigant, but I found that the HEMI heads have larger thermostat outlets than the HSC or the Lean burn heads.

Casting lable & code info:
The most important thing on a head is the casting lable. It can be located at the top and center of the intake side of the head, and will read something like this: RF-E5EE-A7E. That number holds the key information about that head. Namely the casting year, and the design/application code. The casting year can be identified with the 1st and 2nd digits in the 2nd code group on the lable RF-E5EE-A7E. ford uses an alpabetical lettering code for the tens place (decade) of the year, so A = 1940's, B = 1950's, C = 1960's, D = 70's, E = 80's, F = 90's and so on. The 2nd digit is the specific year code, 1 = 81, 2 = 82......ect. So an RF-E5EE-A7E is a 1985 casting. Now the design code is needed to identifiy that heads engine application group. It is the last code on the lable, so in this case it's A7E
Another lable on the head is the casting plant I.D. It can be found in the upper right hand corner of the intake side. I have seen a number of different plant I.D.'s The most common is: Essex, CAE, NL, DJ, and one that looks like a little pyramid of four lines. and they are followed by a number; 1 - 99. Another code that you may or may not find is the ford part code 6090 between the casting year and the design code: RF-E5EE-6090-A7E. The 6090 is the code for a cylinder head. Hopefully this lable information can be used with good old trial & error, too see the benifits or downsides of using one head over another. For more information about reading Ford casting numbers, just search the web. there are a handfull of great sites on the subject.

Here is a list of all the different casting lables I have gatherd, their corosponding engine group, and some info about the group.

Reference:
HEMI......... Hemispherical chamber

HSC.......... High swirl chamber

LB............. Lean burn, semi-hemi, D shaped dome chamber

Small exhaust port size:..... 35mm high x 32mm wide
Large exhaust port size:..... 40mm high x 39mm wide
HEMI valve dia.:............... int. 41mm, exh. 37mm
HSC valve dia.:.................int. 41mm, exh. 37mm
LB valve dia.:........ int. 39mm, exh. 34mm

Small Thermostat outlet: 31mm
Large thermostat outlet: 38mm

---------------------------------------------------------------
81' - 82' 1.6L carb; (HEMI):
All:
round intake ports, 34mm high x 29mm wide
large exh. ports
large therm. outlet

castings:
RF-E1EE-6090-A4C
RF-E1EE-6090-A5C
RF-E1EE-6090-A6C
RF-E1EE-6090-A7C
RF-E1EE-6090-A8C
-----------------------------------------------------------------------
83' - 85' 1.6L carb, carb HO, EFI, EFI Turbo; (HEMI):
Ford part stock #: E3FZ-60490-A
Just so it's clear, I've seen everyone of the head castings in this group in a turbo application
All:
round intake ports, 36mm high x 32mm wide
large exh. ports
large therm. outlet

castings:
RF-E3EE-6090-A4A
RF-E3EE-6090-A5A
RF-E3EE-6090-A6A
RF-E3EE-6090-A7A
RF-E3EE-A7A
------------------------------------------------------------------------------
85 1/2' - 86' 1.9L carb; (HSC)
All:
round intake ports, 36mm high x 31mm wide
small exh. ports
small therm. outlet

castings:
RF-E5EE-A4E
RF-E5EE-A5E
RF-E5EE-A6E
RF-E5EE-A7E
RF-E5EE-A5A
RF-E5EE-AF
RF-E5EE-AH
RF-E5EE-BB
---------------------------------------------------------------------------
85 1/2' - 86' 1.9L EFI: (HEMI):
All:
round intake ports, 37mm high x 33 mm wide
small exh. ports
large therm. outlet

castings:
RF-E5EE-F4A
RF-E5EE-F7A
RF-E5EE-FA
RF-E5EE-FB
-----------------------------------------------------------------
87'- 88 1/2' 1.9L CFI; (LB):
All:
oval intake ports, 37mm high x 28mm wide
small exh. ports
small therm. outlet

castings:
RF-E7EE-D4C
RF-E7EE-D4F
RF-E7EE-D7C
RF-E7EE-D7E
RF-E7EE-D7F
RF-E7EE-A7E
RF-E7EE-A
------------------------------------------------------------------------
89' - 90' 1.9L CFI; (LB):
These are the same as the previous Lean burns, but all the ones I saw had roller cams.

castings:
RF-E8EE-A7A
RF-E8EE-AA
RF-F0EE-A7E
RF-F0EE-B7A
RF-F0EE-B74
------------------------------------------------------------------
87' - 90' 1.9L EFI; (HEMI):
All:
round intake ports, 37mm high x 33 mm wide
small exh. ports
large therm. outlet

castings:
RF-E7EE-G4A
RF-E7EE-G4D
RF-E7EE-G4E
RF-E7EE-GB
RF-E7EE-GC
RF-E7EE-G7A
RF-E7EE-G7C
RF-E7EE-G7D
-------------------------------------------------------------
Here are a few block castings I found also also:

Castings:
E5EE-AA
E5EE-BE
E7EE-BB
E7EE-FA
E8EE-AA

------------------------------------------------------------------
I try too update this regularly as I find more information, I hope to build a web page so I can be more specific and and show pics to help better explain the information I'm sharing.
Thanks for reading, Sean....................

 

[gt19ho]

God im glad to made it over here sean. This man knows his 1st gen head guys. This needs a sticky post haste.

 

[highanddry]

I've never seen you on here before and I already vote you "contributor of the month." And I hate 1st gens to boot. Nice write-up.

 

[rudedog]

This is a great write-up Sean!! As you can see from my avatar I own an '89Lx, it's been sitting in my back yard for about 3 years, while I've been trying to iron-out title problems. Now that It's leagal to drive on the street (registered,etc.) it became my daily driver so I could mod my Taurus, although I find myself doing both cars at the same time. The little thing really does run excellent for having 130,000 on the ODO, anyway, I see you have the specs for the 1.9. Is there any room for MAJOR improvement by doing any kind of port/polish, extrude hone, any machine work, does anyone sell bolt on power modifiers? From what I see it looks like the heads are designed from the factory very well already.

 

[Jeffescortlx]

Awsome job! Now can you do the same with the 2nd and 3rd gen SOHC's???

 

[CIRCLESCORT]

Will the '83 -'85 1.6l carb head work with the domed 1.9 HO pistons ? Will all of the hemi type heads work with the domed pistons ?
I like the idea of larger exhaust ports for circle track racing !

 

[scortster]

Sorry to keep you guys waiting so long, I haven't been on in a while.

performance gains?

What engine are you going too run? 1.9l CFI or EFI HO

Awsome job! Now can you do the same with the 2nd and 3rd gen SOHC's???

Thanks Jeff, I wish I could have the free time to do the same reserch for you 2nd and 3rd Gen guys, Unfurtunatlly I hardly seem too have enough time for myself anymore.

Will the '83 -'85 1.6l carb head work with the domed 1.9 HO pistons ? Will all of the hemi type heads work with the domed pistons ?
I like the idea of larger exhaust ports for circle track racing !

Yes, all of the HEMI heads can be intercanged.

I personally would not recommend using a earlier casting for your application. Although the the exhaust ports are larger on the 1.6L heads, the intake ports are substancially smaller than the 1.9L HO ports. The larger exhaust ports are good for a HP gain at the top end, with a price of some low to mid range torque. The CVH's really like to breath in, But sense you are unable to do any porting work too the intake you wouldn't be able take advantage of the larger exh. ports.
In my opinion, you a best off running a the late model 1.9L HO head. They have the largest smoothest designed intake ports, and the smaller exh. ports won't be a harm to performance.

 

[rudedog]

Well I guess that I have the CFI now, it's bone stock. What would be the best combo to go with?

 

[scortster]

Well as far as performance goes the 1.9 HO motor swap is the "best combo", But like most of us a swap usually isn't an option. Here are couple suggestions for getting some more power out of the CFI motor.

Starting with a freshly rebuilt motor is aways best, but it's not necasary.
You should first do a general tune-up including a cylinder compression to make sure that the engine is in overall good mechanical condition. If everything checks out, it's on modifing.

One of the easiest was too get power is to increace the stock base timing. Stock setting is 8* BTDC, I found that running about 14* BTDC gave the best results for me. Make sure to run at least mid-grade gas with the higher timing thought, regular pinged under acceleration.

Another fairly easy way is to replace the exhaust manifold with a tubular header from a GT. The header makes a nice differance in the power band, that I feel is well worth the effort to do. Depending on your emissions laws, you will need a Catalytic converter. The header will delete the cat on the CFI setup. A high flow converter is a good replacment and upgrade.

A 1.9 HO cam swap is also good. The cam is not a very radical change from the CFI cam, it offers slightly higher lift, longer duration and a bit more overlap. In my experiance the GT cam mosty shifts the power band up alittle. It show more HP in the upper revs (3500+ RPM), but you lose just a tiny bit of low end torque before 2000 RPM. The cam is a nice compliment to the header and up'd timming. Let me also add that if you decide to do the cam swap, you should replace the old lifters with a new set. If the lifters in the car are the originals, it's a good bet their shot.

Now opioinally speaking, I do not beleve the CFI motor to be worth expensive modifications like porting, exc. Though there is room for improvment, the cost and time v.s. the overall gain would most likly leave you with buyers remorse.

Turbocharging is also possiable on the CFI, and has been done before succesfully. I have no personal experiance with a turbo CFI setup so I really couldn't be much help there.

Hopefully this helps, and if you've got any other questions feel free to ask.

Sean....................

 

[rudedog]

Thanks alot Sean, just what I was looking for!

 

[Recrdholdr]

Scortster.. Just thought I'd let you know that the 81-82 1.6l head also cam in a A7C and A8C version.. Nearly Identical in every aspect though..

 

[scortster]

Thanks for the info Recrdholdr. Seems like every time I turn around, there are more castings #'s to add to this thing.
"WHEN WILL THE MADNESS END? WHEN I ASK YOU. WHEN!.............."

:lol:

 

[stealth83]

heads

is it possible to switch over from a 1.6 carb 2 a turbo head and if so is it even feasable...

 

[CIRCLESCORT]

How much can be safely milled off of an '87 HO head ?
Can there be enough removed to realign the cam timing ?
It seems that I have removed .050 and the resilt was about 1/2 tooth off on the cam timing which tells me that .100 would realign the belt again. At .050 I left the cam retarded and it was really strong on the top end but really softened the bottom.


PLEASE HELP !
I don't have time for trial and error !

Thanks in advance
Rob

 

[scortster]

Re: heads

is it possible to switch over from a 1.6 carb 2 a turbo head and if so is it even feasable...

Sure it's possible, the two heads are almost identical. There isn't anything to be gain though, unless you are replacing an earlier casting (say an '81) with a later one ( '83 & up). The int. ports on the later heads are a little bigger.

 

[scortster]

How much can be safely milled off of an '87 HO head ?
Can there be enough removed to realign the cam timing ?
It seems that I have removed .050 and the resilt was about 1/2 tooth off on the cam timing which tells me that .100 would realign the belt again. At .050 I left the cam retarded and it was really strong on the top end but really softened the bottom.

PLEASE HELP !
I don't have time for trial and error !

Thanks in advance
Rob

I think .075, .100 is more than I would ever personally push a head. I'm not an authority on skiming heads to there limits though. You should toss that question out to the crowd here. I'm sure someone around here will know better.

The head can not be milled enough to bring the cam back in to alignment. To make a one tooth differents you would have to mill something like .250 off the head.

 

[CIRCLESCORT]

PIE R SQUARE ?

Your right, I did a little measuring and a little math, it would be something like .250 to return the cam into correct timing. If my math is correct, .040 would retard the cam 2deg. at the crankshaft, completely acceptable for circle track racing, moving the power range a little closer to the top.

 

[scortster]

PIE R SQUARE ?

What the heck are they teaching in school? Everyone knows that pies 'r round, cakes 'r square. :lol:

 

[Russell]

Some excellent info dude................I just learned more about my '90 1.9HO in 10 min, than in the 2 yrs I've owned it. We need to print some stickers.....YES it's got a HEMI!

 

[rpricew]

Nice post!

Thank you