Strange 292 head problem

[metro1]

I removed the heads from another engine and had them reworked at the machine shop. I was installing them today and ran into something I had not experienced before. On the drivers side head the top holes in the head do not exactly line up with the threaded holes in the block. The bolts drag against the front of the holes in the head. I tried it back on the old engine and the same thing. It must be bored wrong. The bolts will go in but the drag will make torqueing it incorrect. I am using ARP bolts which have a smaller shaft diameter except for the top 5/16 so they only scrape there. At this point I could shave a few thousands off of the top part of the bolts but I really don't want to do that. I guess I could open up the front top of the holes in the head. Has anyone ever ran into this?

[paul2748]

If you belong to Y-blocksforever.com I would run this question there if no one here can help you.

[55blacktie]

Metro, were the cylinder head guide pins removed from the block? If the pins were removed or replaced with the wrong pins, that could explain your alignment problem. I've read of head bolts being too short/too long after milling heads or using thicker/thinner head gaskets. The same can also cause alignment issues with the intake manifold, which can require either milling the intake or the intake side of the heads for proper alignment. However, I've never heard of milling/surfacing heads to cause alignment problems with the block. I suppose it's possible more was milled from one end/side of the heads. Try measuring the center pads near the spark plug holes on the exhaust side of the heads. The pads should be 1.010 for heads that have not been surfaced/milled. After measuring the center pads, compare the measurement to the end pads. If they are not the same, that could be your problem. It's not likely that a caliper will give a precise measurement. It's best to use a micrometer that's been calibrated. It might require a return trip to the machine shop.

[metro1]

The other head fits good. On this one the bottom (short bolts) are aligned good and go right in with no interference. It's the top bolts that all scrape the front of the holes on the head. It fits the same way on the engine it came off of. I removed the bolts with an impact so I don't know if they tight before or not. I assume both heads were done the same way at the machine shop . I can't figure why one fits good and the other doesn't. The old engine did have a blown head gasket so maybe it was bad already and didn't get torqued properly. None of the alignment pins were removed. There was a crack in one of my heads so I used these.

[55blacktie]

If you are not a member of y-blocksforever.com, you will not be able to post your question. You can, however, send an email to Ted Eaton ([email protected]). Ted usually replies within 24 hours. Ted can also explain to you the registration process for y-blocksforever.com.

[metro1]

Sponsored Links (Register now to hide all advertisements)

That's a good idea. I'll have to get with Ted and join up.

[KULTULZ]

Originally Posted by metro1

That's a good idea. I'll have to get with Ted and join up.

And come back here and post what you find. I am curious also.

[55blacktie]

Metro, I just reread your original post. Is it possible that the ARP head bolts are the problem, not the heads? There have been a number of complaints regarding the ARP rod bolts not fitting OEM Y-block rods; there isn't sufficient clearance for the bolt heads. A suggested fix has been to grind the bolt heads down for clearance.

Can you check alignment by using the original rod bolts?

[KULTULZ]

A suggested fix has been to grind the bolt heads down for clearance.

I would consult TED EATON before doing this.

[KULTULZ]

The bolts will go in but the drag will make torqueing it incorrect. I am using ARP bolts which have a smaller shaft diameter except for the top 5/16 so they only scrape there.

The bolt shank touches the cyl head hole before the hex cap reached that point?

[55blacktie]

Grinding bolt heads is in reference to the rod bolts, not head bolts. I've read that both Ted Eaton and John Mummert suggested grinding the ARP connecting rod bolt heads to provide rod-to-bolt-head clearance.

In Mummert's YouTube video on their H-beam connecting rods, the difficulty of finding connecting-rod bolts that fit OEM rods is mentioned.

[metro1]

With the washer installed there is 3/16 of the large portion of the shank below the cap that scrapes the side of the hole. I think I'll just open the hole in the area that causes the interference a few thousands with a die grinder and move on. I don't see where it will hurt anything and it will allow the bolts the turn freely.

[55blacktie]

I don't know how thick the casting is in that area, so be careful. I suppose there could be casting flash/residue that's causing an obstruction. There might be just enough difference between the OEM head bolts and the ARPs to cause the interference.

[metro1]

I have a picture of the problem. How do I send it?

[KULTULZ]

Originally Posted by 55blacktie

Grinding bolt heads is in reference to the rod bolts, not head bolts. I've read that both Ted Eaton and John Mummert suggested grinding the ARP connecting rod bolt heads to provide rod-to-bolt-head clearance.

My thought is that either the block deck and/or the cyl head itself has been wrongly angle cut.

If one goes to grind on the fastener, it may weaken it or if the fastener is found to be defective itself, you will not be able to return them.

The problem is on one side of the short assy. I would want to know how TED or JOHN interprets this before going neanderthal.

On the drivers side head the top holes in the head do not exactly line up with the threaded holes in the block. The bolts drag against the front of the holes in the head. I tried it back on the old engine and the same thing. It must be bored wrong. The bolts will go in but the drag will make torqueing it incorrect. I am using ARP bolts which have a smaller shaft diameter except for the top 5/16 so they only scrape there.

[KULTULZ]

Question and thread continued @ y-blocks forever.com -

- http://forums.y-blocksforever.com/Topic165303.aspx

I need to know the answer myself.

[KULTULZ]

A quick couple replies already -

TED wrote -

From the description you give for the friend’s cylinder head, it was resurfaced without care to ensure that the deck surface was square to the grinding or cutting tool when the head was resurfaced. If that is indeed the case, then the angle between the head surface and the intake mating surface will be different. If one cylinder head bolts down fine, then use that angle as a comparison to the deck to intake angle on the head that’s having a head bolt issue. Another telltale would be if the head bolt hole at the bottom of the head is not square with the deck surface of the head. A machined bar that fits the head bolt hole at the bottom of the head would help to determine that either with some layout dye or a square or a dial indicator. Several options there.

And then there is mention of the intake not fitting correctly as is.

[metro1]

Thanks Kultulz. I saw the replies on the other site. I contacted Ted today and he gave me a time to sign up tonight. It's not really off that much so I think I'll use the other guys suggestion and take out a little with a burr grinder in the affected area and hope for the best outcome.

[metro1]

image0 (4).jpeg All of the top bolts look like this. This is without the washers. They go in fine until they get to the top larger part of the bolt.

[55blacktie]

I would use a sanding roll instead of a burr grinder, being careful to only remove the amount of material necessary. check your progress frequently.

[KULTULZ]

If you decide to go that route, check closely for vacuum and coolant leak(s) when you install the intake.

Have you thought of going back to the machine shop and see if they will deck it correctly?

[KULTULZ]

... don't ask ...

[KULTULZ]

Originally Posted by metro1

I saw the replies on the other site. I contacted Ted today and he gave me a time to sign up tonight. It's not really off that much so I think I'll use the other guys suggestion and take out a little with a burr grinder in the affected area and hope for the best outcome.

I would use a sanding roll instead of a burr grinder, being careful to only remove the amount of material necessary. check your progress frequently.

What the man says. Be very careful here as you do not want to gouge the material possibly leading to material weakening/stress cracks.

I understand it is not a HI-PO build but still ...

ADDENDUM -

More knowledge from TED -

As a general rule, always check the head bolt holes in the blocks for being threaded deep enough. I will install the bolts first without the washers to ensure that the bolts do go deep enough and then reinstall with the washers. The ARP washers have a bevel on one side and that bevel must go up and against the head of the bolt.

[KULTULZ]

metro1,

They want the CYL HEAD CASTING ID NO over on the other forum if YOU can supply it.

[metro1]

The numbers I see are ECL6090 with an "A" over top of the 0 . Other number 4BA.

[55blacktie]

Sponsored Links (Register now to hide all advertisements)

ECL-A heads were original equipment on 1955 272 Fords and 292 Mercurys. They have a lower static compression ratio (7.6) than the ECL-B/C heads (8.5) as found on 55 Tbirds and 4-barrel 292 Mercurys. Your ECL-A heads, although having the same valve sizes, must have larger combustion chambers, which would explain the difference in compression ratios.

[Gene F]

Would the 8.5's happen to also be the ones used on the 312 T-birds THAT LEFT THE FACTORY AS 312'S?

[metro1]

The ones that were on the engine are ED-ECZ C

[55blacktie]

Those heads have 73cc combustion chambers, used on 56 272 pickups, and have a static compression ratio of 8.5. They have the same valve sizes as the ECL heads.

[metro1]

Will the difference in comp. ratio cause a noticeable performance drop?

[55blacktie]

On a completely stock engine? No. If you have a good quench area (.040-.045), you should get good results running on 87. As originally built, the pistons were about .020 below deck; with the original head gaskets having a compressed thickness of .025, the quench would have been .045. Aftermarket cast pistons can be .035 below deck (assuming the block hasn't been surfaced). Replacing the OEM gaskets with composite gaskets that have a compressed thickness of .046, results in a quench of .081, which could be prone to detonation. The composite gaskets provide a better seal, particularly if the block deck and head surfaces aren't perfect. A zero-decked block with composite head gaskets will provide a decent quench.

[metro1]

I did see an 060 on top of the pistons which I assume is .060 oversize.

[miker98038]

It may be in one of your other posts, I didn’t see it in this one. This is the link to the head casting number and other info from John Mummert’s site. It’s got a variety of other head info, and if you look around his site much more info.

http://www.ford-y-block.com/cylinderheadchart.htm

55blacktie pretty well covered the compression question.

I’d be getting to the bottom of the question on those heads though. Finding out why they appear to be out of kilter, and getting it all squared away first. If it’s minor, fine. But if it’s off enough that the intake doesn’t seat properly you’re going to be chasing vacuum leaks, or water leaks, or possibly head gasket sealing problems.

This is not the time to say “we don’t have time to do it right, but we’ll have time to do it over”

[55blacktie]

Yes, "060" indicates that the pistons are .060 oversize.

[KULTULZ]

Originally Posted by Gene F

Would the 8.5's happen to also be the ones used on the 312 T-birds THAT LEFT THE FACTORY AS 312'S?

You mean original factory assembly before who knows what service/repair/modifications were done to the engine? What year BIRD are we talking about?

[KULTULZ]

Originally Posted by metro1

I removed the heads from another engine and had them reworked at the machine shop. I was installing them today and ran into something I had not experienced before. On the drivers side head the top holes in the head do not exactly line up with the threaded holes in the block. The bolts drag against the front of the holes in the head. I tried it back on the old engine and the same thing. It must be bored wrong.

The head was at some point decked incorrectly as it will not fit correctly on either block.

To correct this, the head will have to be re-surfaced square and depending on the amount of material required to be removed to accomplish this will/may raise the CR on that one bank due to lessening CC as cast by the factory. The other head would also have to be cut to match this one are the engine will be operating with different CR from side to side.

Another thing to remember is even though the head has a distinct CASTING ID NO, it may have gone through differing machining protocols to meet the assembled engine needed calibration (may be differing combustion chamber volumes). In short, one would have to CC the combustion chambers to see it it is in calibration for a particular engine or has been possibly previously machined.

Now we are getting into selective fit and/or blueprinting and that equates to $$$. It is going to make a difference whether the car will be a driver, street/strip or especially competition.

Due to the age of these engines and parts, they need to go on the forensics table to verify exactly what you have to work with before spending the big bucks.

Case in point, recently watched a U2 short about a guy with a 396 CHEVELLE (and you respected these damn things back in the day). Somewhere he had lost his take-off heads and was wanting to bring the car back to numbers correct. Finally found a set (CASTING ID correct and DATE CODES within a few days of one another) on FleaPay and when he got them ($$$) they were pure junk.

- !!! CYA !!! -

[55blacktie]

According to Ted Eaton, milling the ECL heads .0063=1cc reduction in combustion chamber volume.

[miker98038]

If you go to the link to Mummert’s site, you’ll see the “factory” compression spec for various heads and the variance from using them on a 292 vs a 312. Keep in mind few if any engines from the factory would actually cc out to meet the advertised compression ratio.

Then you add the over bore, and it changes again. My bored and stroked 292 (320 cid) with the Mummert heads cc’s out at around 10.75 static. Which starts the whole conversation between static and dynamic ratio. We can ignore that here.

I wouldn’t worry much about slight compression variations even from one bank to another. It won’t be a problem on a stock or mildly modified street engine. I would be more concerned about things being “square” as I stated above.

[Gene F]

Originally Posted by KULTULZ

You mean original factory assembly before who knows what service/repair/modifications were done to the engine? What year BIRD are we talking about?

I guess I am asking if a person has a 312, that was shipped out of the factory as a 292 and the heads were put back on it, what compression is that upgraded 292 likely to be? I feel like the 312's that left the factory that way are superior to a 292 that has been punched out. I keep telling people yes they are a 312 CID, but they are not the same engine that you think they are when you refer to a "Thunderbird 312".

[KULTULZ]

Originally Posted by metro1

The numbers I see are ECL6090 with an "A" over top of the 0 . Other number 4BA.

To Wit -

[KULTULZ]

Originally Posted by Gene F

I guess I am asking if a person has a 312, that was shipped out of the factory as a 292 and the heads were put back on it, what compression is that upgraded 292 likely to be? I feel like the 312's that left the factory that way are superior to a 292 that has been punched out. I keep telling people yes they are a 312 CID, but they are not the same engine that you think they are when you refer to a "Thunderbird 312".

IF a person took a 292 and built it into a 312, it is a 312 (CI).

IF a person did the same and claimed the engine was numbers correct for a particular classic car - /and/or dedicated restoration or possible survivor -, then it would be fraud (IMO) (unless very careful about CASTING and DATE CODES) (maybe)(and was not declared to be the original engine).

CR/HP would be determined by parts chosen and modified. The year of the engine would determine how much you could get away with (say 1957 assembly as compared to 1956).

To find true CR, one would have to CC the heads and cylinders. Even the use of different style head gaskets would affect final CR.

Does that help?

[KULTULZ]

Originally Posted by miker98038

I wouldn’t worry much about slight compression variations even from one bank to another. It won’t be a problem on a stock or mildly modified street engine. I would be more concerned about things being “square” as I stated above.

I would worry as if I took the heads to a machine shop and either they failed to notice/check the actual cause of the malady, you are out of a lot of money.

If just a sight difference between the banks, it may not be noticeable but a large difference will (rough idle/spark plug readings). How well does an engine run with one or two dead/near dead cylinders?

Whatever one's interpretation may be, it was good Yankee money spent for the incorrect outcome. Now will the shop stand behind it's work?

Would I assemble the engine with that head? No way (especially a customer's car). Grind down head bolts and pray she sits down correctly? You are just begging for it.

[55blacktie]

It's a good idea to involve the shop that did the heads before you do anything to them. They might fail to accept responsibility and blame it on you.

[miker98038]

I went back and reread this, and all I found is the machine shop “reworked” the heads. I guess that could mean a lot of things, from hot tanked and lapped to milled, guide’s, guides cut for keeper clearance, etc. I could go on. So that’s a business problem to me. Did you get what you paid for? Still a problem.

I’m still more concerned (I don’t know the term) that everything is in spec -straight and true-flat-fits properly.

[KULTULZ]

The whole damn thing is just enough to p!ss you off, ain't it?

[58Yeoman]

Sponsored Links (Register now to hide all advertisements)

^^Yes, it is enough to piss you off.^^

I'd never put it together that way and hope that it's okay. You will ALWAYS be thinking "is it going to hold?"

When I was into VW's in the 70's, I had all my heads done by a local shop. I took four pair of heads to be done, they did a great job. My mistake was taking a pair of 1200cc dual port heads to be redone. I paid for the job, but had no use for the heads. I ate the cost and never used them. Just the cost of doing business.

If the machine shop can't/won't fix the problem, I'd be looking for another head.

[55blacktie]

And another machine shop.

[KULTULZ]

... chirp ... chirp ... chirp ...

[KULTULZ]

Originally Posted by KULTULZ

Case in point, recently watched a U2 short about a guy with a 396 CHEVELLE (and you respected these damn things back in the day). Somewhere he had lost his take-off heads and was wanting to bring the car back to numbers correct. Finally found a set (CASTING ID correct and DATE CODES within a few days of one another) on FleaPay and when he got them ($$$) they were pure junk.

Here is the video -

- https://www.youtube.com/watch?v=1RJ78O8KrA4

[55blacktie]

I was a senior in HS in 1973 and owned a 1969 SS396/w 375-horse L78 (same engine rated 425 in 65) and L88 427 cam. Needless to say, breaking the tires loose was easier done than said. I didn't keep it long, however, because I couldn't afford $10 per day for gas. My folks didn't appreciate the raw-gas smell in the garage.