Rebuilding Cylinder Head

Redfalken

Well-known member
I recently bought a E0BE-6090-BB cylinder head with a cast date of 2H19 (August 19, 1982) to rebuild. I paid $25 for the head and brought it to the machinist to get hot tanked and magnafluxed. It was in good shape and has never been rebuilt.

head.jpg


I found a place north of Seattle that specializes in cast iron repair and got the port divider welded in. The uneven part of the weld should be gone as I'm getting the exhaust port surfaces milled flat.

divider.jpg


I also had him fill in an exhaust manifold bolt hole that was almost stripped and was missing a good part of the tab from when it was cast. I'll bring in a manifold so he can drill and tap a new hole and get it properly aligned.

tab1.jpg

tab2.jpg


There was also a large hole and two bolt holes under the carb base that had an EGR device attached. I had him fill this in as well. I had originally cut the base off the EGR piece and ground it flat. I was going to bolt it on with a gasket and somehow get a fitting in the large hole but I can now just drill and tap for whatever fitting I decide to use to draw vacuum for the PCV and tranny modulator. There was also a tiny crack from the carb opening to the EGR opening that he repaired.

egr.jpg


He heated the head to a dull red and did the welding (using cast iron rods) while it was in a smaller brick oven with torches blowing in on each side to keep it hot. It then went back in the furnace for a slow cool down. The place was called "Cast Iron Repair Specialists" and the guy really knew what he was doing. It cost $100 but was worth it to me.

I've done a lot of searching on this forum and have the latest edition of the "Performance Handbook" but wanted to run my "to do" list by everyone here to see if you have any comments. I plan to do most of my porting and polishing before I take it to the machinist. The guy specializes in heads and I get a feeling that he will do a great job.

Parts supplied:
- Oversized stainless steel valves (1.5" exhaust, 1.75" intake)
- Teflon valve seals
- Head gasket
- Exhaust manifold (to position new bolt hole)

1 - Install hardened valve seats.
2 - Three-angle valve job (Top Cut: 30°, Valve Seat: 45°, Bottom Cut: 60°).
3 - Undercut intake valve 30° (do not undercut exhaust valves).
4 - Install bronze valve guides.
5 - Machine for teflon valve seals.
6 - Unshroud valves (I will smooth the chambers and even volumes).
7 - Mill head .030 to .060 as needed.
8 - Mill exhaust port surfaces as needed.
9 - Drill and tap under carburetor base for vacuum fitting.
10 - Drill and tap front tab for exhaust manifold bolt.
11 - Mill carburetor base surface as much as possible.


Thanks in advance for any comments...
 
Good! I like getting a bargain...

The place was an hour's drive north so a coworker who lives nearby picked it up for me and I didn't get a chance to talk with the welder again. I dropped it off so I could see his setup and go over the details. One thing I noticed was it looked like it had been media blasted. I found a few remnants of the media that look like tiny, round metallic pieces the size of a grain of sand.

Would he have shot peened the entire head? I was thinking maybe since it was superheated and cooled this might be a part of the process to strengthen the iron. I'm not real familiar with shot peening. I've just heard about it being done to push rods after they've been ground to balance.

Anyone see anything to add to my list? It will be a pretty stock engine. Just trying to get a little more power out of it.
 
I appreciate your web site as it outlines so many items. I look forward to following along this build with you. Thanks for sharing.
 
Howdy Back Kenny:

Sounds like a good basic plan. I have some questions for you though.

What is your intended use for this engine? What is your Compression Ratio goal? What head gasket will you be using? What block will this head go on? What carb will you be using? What exhaust?

When porting & polishing, be very careful to not nick the valve seat area. In the intake I'm more concerned with smoothing irregularities and casting ridges. Concentrate on smoothing the transition between as-cast and machined surface transitions. You don't need to get carried away with polishing the intake side. Be sure to port match the exhaust ports to the gasket. Reshape the port divider to match the others. You can smooth and shape the inside of the cast exhaust manifold too.

Your time and effort will be best spent in smoothing and polishing the combustion chamber surfaces.

Keep us posted on your progress.

Adios, David
 
HEY KEN


.....HOWDY AGAIN. THIS IS LEROY FROM SAN JOSE. I THINK THAT HEAD ALREADY HAS HARDENED VALVE SEATS. CHECK IT.

.....I WOULD LIKE TO SEE YOUR CAR AGAIN AND RIDE IN THIS TIME. NEXT TIME YOUR TAKE IT TO A SHOW. GIVE ME A HEADS UP IF IT'S IN CALIF.

.....I LIKE YOUR PIECE ON THE 8" READ END. GREAT JOB.

LIVE IN GRACE

LEROY POLL
 
For now I'll just be putting the head on my existing `69 200 block, Weber 32/36 DGEV, stock cast iron manifold. I bought a Fel-Pro gasket. Eventually I'll put more thought into rebuilding a block and putting on some headers as well as picking out a cam. Just need some more $$$

I want to end up with an engine that has a decent amount of power but I won't be burning rubber. Mileage is a concern but my commute is pretty short so I don't really spend a bundle on fuel. I want it to run smooth and be reliable. I like it to look as stock as possible but do as many modern improvements as I can. It's my daily driver.

I've never ported before but I did get a DVD on eBay with a pretty good demonstration of the process and have read about it quite a bit. I've got a nice die grinder, carbide bits and I'll order a porting kit. Gotta get a variable speed control for the die grinder too.

Hi Leroy...I hope I can make it back down to CA sometime for a show. From what I understand, the seats were induction hardened, meaning just the surface of the iron is hardened with heat. When the head was heated up to weld, that basically ruined that hardening. Also, since I'm putting in larger valves, I'll need to have the openings enlarged so hardened seat inserts will be put in.
 
Do all the porting and relieving before you have the seats installed. Pay particular attention to the valve pockets and guides. They are terribly restrictive.

When working the exhaust ports, try to make them taller. They have a slight downward turn at the end of the runner and benefit from working them that way as opposed to making them a lot wider to match the manifold. Port the manifold to match the exhaust ports.
 
Kenny,

When I had my head in the machine shop for its rebuild, pretty much the same as you are having done, the machinists questioned me on a few things.
First, was the teflon seals, he said they do work good, yet sometimes too good and not allowing any oil at the stem of the valve. More heat/stress he acknowledged and said the bronze valve guides would be enough with the regular umbrella seals, or maybe he was just lazy and did not want to machine for them. Also the price for the machining would have been way more, but money was no object at that time and I wanted to do it right. He did manage to keep my head for, I think 8 weeks before returning it to me finished. He was retired and took his time, and for over four counties here in Texas he was reknown for his work. He did a wonderful job though and only charged me $450.00, I guess he felt bad for having it soo long...sorry, ranting away, now back to you.
The other was hardened valve seats, this was a D5** head and had none, so I asked him to machine for those, too being I was going turbo with this engine. Again maybe he was lazy and did not want to burden with it, but he said if it wasn't a daily driver with 100 mile round trip, don't worry about hardened seats. So I took his advice and did not have it done. Cost would have been greater, also and alot more time involved.
The only other thing I can remember was him talking about the one piece retainers I was going to use instead of the stock one (the ones from the 4.0 V6). He mentioned that they do not let the springs rotate while on the head as well as the two piece,which help with spring distortions. I think that is what he said.
I also did not use the port divider, either. He said he did not think it would really make a difference in his mind, maybe only a place for more heat transfer vs. its potential for flow characteristics.
Now take into mind this is what the machinist said to me, not that it is right or wrong or whether it makes no difference at all. I thought I would just share what I went through during my rebuild. Best of luck to ya.

Anybody care to elaborate about what this machinist was telling me?

Kirk
ps. nice deal on the cast iron weld, mine was $150 and ended up cracking.
 
Redfalken":38u3ei28 said:
I was going to bolt it on with a gasket and somehow get a fitting in the large hole

Funny^

Just flip it 180*
EGRblockoff.jpg
 
Howdy back All:

Kenny- On CR, I'd plan now on whether you plan to build the shortblock with a zero deck height. If you do, decking the block .025" to .030" will raise the CR. In figuring your goal CR, I'd plan my head milling based on the future block decking plan. IIWY I'd plan for the zero deck height to maximise the quench effect in the combustion process.

Kirk- I think your greyhair is a hard core traditionalist. He is giving you the basic Ford Falcon six cylinder basic-to-the-core line. All of your suggestions to him had him thinking outside of his comfort box. In fact, the port divider, seat inserts, bronze guides and teflon seals and one piece retainers will have a marginal return at best and are really only worth the money if you feel the need or as performance levels go up.

Adios, David
 
Howdy Again:

I ran some numbers on the CR calculator-

If your were to put the stock E0 head, with the chamber volume reduced to 52 ccs by milling it .050", and used a .050" thick FelPro head gasket, assuming a .025" deck height and a standard bore, your CR will be 8.5:1.

When you rebuild the block assuming a .030" overbore, 6.5 cc dished pistons, zero deck height with the same chamber volumes and head gasket thickness as above your CR will jump to 9.2:1.

With a stock cam and 85 octane gas, that might be a bit too high. However with a mild performance cam, to bleed off some cylinder pressure, and some cleaning up of the chambers, and an occasional shot of 91 octane gas through those hot Seattle summers, you might be safe with a 9.2 CR.

If you feel this CR is too high, I'd mill less, leaving a little more chamber volume, and plan for a zero deck clearance on the block build.

What is your CR goal?

Adios, David
 
Kirk...I'll probably go ahead with the mods I described. I've heard mostly positive talk about them and I can't see that they would do more harm than good (but I'm a real newbie with rebuilding an engine). The guy who's going to do my machine work specializes in heads (Hill Machine Headworks) and he seems pretty receptive to doing the work. He didn't charge me for the hot tank and magnaflux and his ears perked up when I told him there was a port divider available. Last year I had him mill a warped exhaust manifold and he did a great job, fair price and didn't take forever.

Linc...flip it 180 degrees...brilliant!! I never would have thought of that.

Lot's of great stuff to think about David. A 9.2 CR does seem a bit high from what I've read. Maybe I should just get the head milled .030? What does your calculator put the CR at if I did that and put it on my current block (.025 deck height, standard bore and FelPro gasket)? I usually run Chevron Plus with an 89 octane rating. And I do plan on a zero deck height. I've also rebuilt an adjustable rocker arm assembly to put on it.

Has anyone heard of grinding a smooth groove in the quench area going from the middle, outer edge to the chamber area (splitting it in half) to improve the quench effect? Maybe it's supposed to direct the swirl and turbulance into the chamber more efficiently???
 
Redfalken":39aam4p3 said:
Has anyone heard of grinding a smooth groove in the quench area going from the middle, outer edge to the chamber area (splitting it in half) to improve the quench effect? Maybe it's supposed to direct the swirl and turbulance into the chamber more efficiently???

I wouldn't. Perfect quench would be having the engine built so the piston comes within .001" from hitting the head at max RPM (don't laugh, some racers do!)

If you got custom pistons that mirror-imaged the combustion chamber the groove might work, but off the shelf pistons just have a plain ol' round shaped dish.

I think 89 octane would be just fine in a 9:1 engine, IMHO.

When doing some port work, do what you can to unshroud the valves the best you can.
 
Howdy Kenny:

Just milling the head .030" to achieve a 57 cc volume chamber, stock bore, FelPro head gasket at .050" compressed thickness, and .025" deck height gives a CR of 8.1:1.

With a rebuilt block overbore of .030", deck height of zero, and all else the same CR increases to 8.6:1. With a stock cam and 89 octane gas that's well within the comfort zone for the fat air around Seattle.

If you intend to step up the cam, even a little, I'd suggest a little more CR.

The "Groove" tech sounds very interesting. I'm doubtful of a noticeable difference with a Ford sixes combustion chambers inefficiencies and inconsistancies. If- the chamber-to-piston dish shape where more similar, creating a higher quench-to-bore ratio, and if a .035" head gasket were available, then- the groove technology would have a greater effect. The only way to know the degree of the effects of the modification is to do controlled before and after testing, noting the changes. Would you want to put your engine together, test it, remove the head for the groove modification, reinstall and test again?

If you decide to try it, be sure to post results. It is an interesting idea.

My Santa wish list still has (1) a .035" compressed thickness head gasket and (2) cast replacement pistons with a dish that mirrors the combustion chamber of the head. Until these two items become available quench related combustion efficiency of our engine is marginal, at best.

Kenny, the modifications and upgrades you have planned will help to make for a very nice street engine.

What do you think?

Merry Christmas everyone.

Adios, David
 
That sounds like a great plan David. Thanks for crunching the numbers and all your advice! It sounds like taking .030 off the head will give me a workable CR until I get around to rebuilding a block and at that point I can have a little more taken off depending on which cam I go with.

Sounds like the mod to the quench area wouldn't be something I want to get into but it's interesting to read about people stepping outside of the box a little.

I've ordered my variable speed control for the die grinder and I'll probably order a porting kit today. I was going to order the valves but it seems the Classic Inlines site is down right now. I'll check back later.

Thanks again for everyone's help and I'll let you know when I get photos and comments on my website.
 
A couple more questions for anyone out there.

First, a few adjusters on my rocker assembly (I'm using an early one for solid lifters) seemed kind of loose so I was going to put jam nuts on. I got some 7/16" - 20 but they seem like the wrong thread?? Or is it just that the jam nut threads are fresh and the adjuster will fit tight if I force it. Also, is there room for a jam nut that's almost 1/4" thick? And will the added weight be bad?

Next, I bought a set of ARP head studs and got the part number 132-4001 (for the set with hex head nuts) from customer service off their website. I was going to put one through the head to see how it looked but it's too thick for the hole. The box lists it for Chevy Inline Six, `62 and up. Anyone know the correct part number or specs?

Last thing, would it be a good idea to repair or replace the spark plug threads? When the head was shot peened the threads got roughed up but maybe that's not a big deal. I was reading about a product called "Time-Sert" that looks much better than a heli-coil. www.timesert.com I haven't tried torqueing in plugs yet to test the threads but just wanted to know if anyone does anything to the plug holes during a rebuild. Also, do you chamfer the surface where the plugs seat? Is it a 45 degree angle?

Thanks again. As soon as the valves arrive, it's off to the machine shop!
 
Back
Top