Author Topic: Top End Rebuild Advice  (Read 3653 times)

newshelby

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Top End Rebuild Advice
« on: October 21, 2019, 07:52:13 PM »
Hi guys,
Had a miss in #2 cylinder that turned out to be a bent rod and exhaust valve issue so the shop pulled the heads and they are off to a machine shop. Because I hope to only have the shop do this once, we may consider just having the whole top end rebuilt. What advice would you offer for top end rebuild components? Is there a kit that comes highly recommended with all parts necessary? Here is what's in the build now. Should I leave these in or have some parts changed out? Want this puppy to last for the long-haul...

Components:

V6 5003 Guides
SB 2125-2 Int Seat
603-16 Comp Locks
CS1086R Cam
HT 900 Lifters
R x R Cam Bearings
E261Kt3C Rings
CB760P STD Rods
MS863P STD Mains
F-33 Cam Bearings
354Pt30 Pistonds

Machine Steps:

Bore and Tork Plate Hone 30 Over
Mill Heads
Mill Exhaust Manifold

Any ideas on % over stock HP this rebuilt may generate? Any other insights?
Thank you.

1967 eight barrel

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Re: Top End Rebuild Advice
« Reply #1 on: October 22, 2019, 09:15:51 AM »
I wouldn't do a .030 over bore. They make .025 over.  I just went through this mess personally. You're block is done at .060 max.
It would likely leave you at least one more build from the block, maybe two depending on the sonic. You start cutting corners you're going to wind up very unhappy with an absolute dog of a motor.  That cam is complete junk. The spec is .484 lift and 215 duration at .050 on that cam. Who is recommending this stuff too you?
It's going to be a complete slug.  You're going the cheapest route and you're going to be very disappointed with this.  There is no horsepower gain, it's a net loss.

newshelby

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Re: Top End Rebuild Advice
« Reply #2 on: October 22, 2019, 11:07:31 AM »
Sorry I should have been more clear. That build list is what was PREVIOUSLY done, about 1,000 miles and 15 years ago. I’m told the cam number on that build list is not the current one by that number from sealed power (which is for a 460), but a number from a previous TRW catalogue which was from the time of the rebuild that included it and the other parts and processes listed. What I am asking now is what top end rebuild parts or kits should I use (now that the heads are taken out) to make the most durable engine going forward? I’m told by the mechanic, and I believe him, that the lower end is fine and cylinders look great with no scoring. Given that one of the existing push rods bent and exhaust valves is faulty, they want to just replace these and put it back together. However, given that the motor sat so long, would you suggest replacing everything else on the top end? And if so what parts? Thanks

KR Convertible

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Re: Top End Rebuild Advice
« Reply #3 on: October 22, 2019, 11:24:25 AM »
Can you expand on "exhaust valve is faulty"?  Is it bent also?  Seized in the guide?  Did they install hardened exhaust valve seats?

pbf777

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Re: Top End Rebuild Advice
« Reply #4 on: October 22, 2019, 11:43:40 AM »
     It is not possible for any individual with the limited exposure to your project, of a forum, to be able to provide an accurate response to your inquiry.  But, you do state: "I believe him", and this is a good relationship to have, so I would advise following those recommendations and hopefully it it is revealed to be accurate. Consider, so in the middle of perhaps a not so critical surgery on one's self, would you typically ask a sum of some forums' participants as to whether they thought the surgery was necessary, or being executed properly, and or perhaps, should one tack on any other procedures while one is anesthetized?      ???

     Now, with that said, and perhaps such had been concluded, but, I suppose an important consideration is, why is there a bent push rod, and how, is the exhaust valve "faulty"?  Perhaps the perceived answer to these questions may prove to be the solution to your inquiry.         ;)

     Scott.

     

newshelby

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Re: Top End Rebuild Advice
« Reply #5 on: October 22, 2019, 11:45:30 AM »
Hi - I don’t know I will ask him. Also, this mechanic (with 45 years of experience and he seems to know his stuff and came highly recommended) is insisting on NOT using a head gasket because he insists they will inevitably leak and is having the heads machined to insure a tight fit. Has anyone heard of this?

427heaven

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Re: Top End Rebuild Advice
« Reply #6 on: October 22, 2019, 11:48:10 AM »
NewShelby- I will try to help with your dilemma, if you ask 10 people a question you will get 10 different answers. In situations like this one has to work backwards from the given problem. For starters why did the engine start to come unglued... An over zealous right foot, or your components were not up to the task, or an inferior build that had mechanical interference problems, you need answers to those questions. Going forward since you asked what percentage of HP will you get, it appears you are looking for an upgrade there. For a simple answer you need a great machinist, and a good mechanic to help with your build. Don't skimp on the dollars here or you will be very unhappy, purchase to best components you can afford and the rest will all fall into place with your pride and joy. Good Luck with this journey.

6R07mi

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Re: Top End Rebuild Advice
« Reply #7 on: October 22, 2019, 12:30:04 PM »
"about 1,000 miles and 15 years ago"

This car appears to not get exercised much, that's less than 100 miles / yr.
What you intend to do with the car would also factor into the repair strategy, IMHO.
If past usage continues going forward,  then would a " repair only what's broken" be logical??

I agree with other comments, a holistic appraisal with knowledgeable machinist / technician with consideration to expected use and budget is prudent.

regards,
jim p
Former owner 6S283, 70 "Boss351", 66 GT 6F07, 67 FB GT
current: 66 GT former day 2 track car 6R07
20+ yrs Ford Parts Mgr, now Meritor Defense

shelbydoug

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Re: Top End Rebuild Advice
« Reply #8 on: October 22, 2019, 01:28:39 PM »
Hi - I don’t know I will ask him. Also, this mechanic (with 45 years of experience and he seems to know his stuff and came highly recommended) is insisting on NOT using a head gasket because he insists they will inevitably leak and is having the heads machined to insure a tight fit. Has anyone heard of this?

No.I never heard of that and in fact, I doubt it.

Head gaskets compressed are normally around .035". There is a clearance that you need to maintain between the top of the piston and the bottom of the head. That number is a minimum of .035".
The top of the pistons are normally around .012" to .015" down in the hole. If you eliminate the head gasket, you will only have at most .015" of clearance. With that clearance, the pistons will hit the heads.

You need a head gasket of at least .020" thick to maintain the minimum piston to head clearance. You can shave material off of the head or block surface but you can't add material too them besides a head gasket.

All surfacing of either would need to consider the "down in the hole" and the intended head gasket thickness.


FE's do have a weak/leaky spot both for oil and water at the extreme ends of the heads. There is both an oil drain back hole there and a water passage.

As a result, surfacing the heads is beyond a good idea, it's almost mandatory to make sure they are as flat as you can get them especially in those areas. This is also where many engine builders will apply head gasket cement even on a head gasket that does not require it.


I'd recommend considering a new cam and looking for one that is a "reproduction" of the 428cj cam. Many manufacturers make them. I don't have a specific part number for you but search on line. Many manufacturers have their catalogs up on the 'net.


You NEED to find the cause of the bent push rod and bent valve. While the heads are off, they should have fresh surfacing to the valve seats and valves.

If the heads have not had hardened valve seats installed DO NOT HAVE THEM INSTALLED. That's a GM thing since GM uses a softer grade of cast iron then Ford does.
In addition, Ford FE heads are very thinly cast between the intake and exhaust ports. You DO NOT want to further weaken them in the valve pocket area. Cutting in for valve seats will weaken the heads there. Not strengthen them.


Personally I'd tell you that if you want to improve the heads while they are apart, have bronze valve guides installed in them. If it turns out that the bent valve is frozen to the cast iron guide, that is further evidence of the need for the bronze guide. The bronze guide will not rust and bond itself to the valve stem.

It wouldn't be a bad idea to change over to stainless valves at this point either.

I'd also change the stock push rods to the hardened type. They will be black vs. silver colored metal. It's pretty difficult to bend them.
68 GT350 Lives Matter!

pbf777

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Re: Top End Rebuild Advice
« Reply #9 on: October 22, 2019, 07:14:17 PM »
is insisting on NOT using a head gasket because he insists they will inevitably leak and is having the heads machined to insure a tight fit. Has anyone heard of this?

     Yes, I have heard of this, but not likely possible in the Ford FE example.  I feel this statement as presented is a miscommunication.      ;) 

     The construction and assembly of an engine with a removable cylinder head(s) not utilizing a gasket was not typical, but also not so uncommon particularly in high performance and expensive engines of long ago; as capable gaskets did not exist, and as such were very susceptible to fairure.  This process did require accurate fitment and often lapping of the surfaces for the required familiarization and sealing qualities, which when all said and done I suspect whether a certain sum of leakage didn't still exist, but one never suffered the failure of a head gasket.  And was more popular in instances of say an iron or steel barrel which could have a brinelling effect into face or receiver of an aluminum alloy or other perhaps yellow metal cylinder head.  Also was (is) more popular with individual cylinder engineering regardless of the number of cylinders the engine (or as also practiced on such devices as air compressors, particularly high pressure units) may exhibit as the fitment/sealing requirement is less exacting, vs say a longer muti-cylinder block & cylinder head unit.

     These types that I am referring to are those which exhibit a bolt-on to a cylinder or even muti-cylinder block type cylinder head, which upon inspection would appear to benefit from a sealing gasket, and not units of "monobloc" configuration, or units with cylinder heads "heat-shrunk", with or with out treading or other interference fitment to cylinders types, which many may also not utilize a head gasket at least not as we are envisioning in this discussion anyway..       :)   

     Scott.

427heaven

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Re: Top End Rebuild Advice
« Reply #10 on: October 22, 2019, 10:26:40 PM »
Your mechanic might be a little confused, you need to run head gaskets which ones of what thickness will require a little math to calculate whats best for your application in the future. what he may be thinking is that you can machine the cylinder head exhaust flange and exhaust manifold sealing surfaces to run without gaskets but not head gaskets! Keep us up to date on your fix.

JD

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Re: Top End Rebuild Advice
« Reply #11 on: October 22, 2019, 10:56:17 PM »
Your mechanic might be a little confused, you need to run head gaskets which ones of what thickness will require a little math to calculate whats best for your application in the future. what he may be thinking is that you can machine the cylinder head exhaust flange and exhaust manifold sealing surfaces to run without gaskets but not head gaskets! Keep us up to date on your fix.

^^^^^ yes
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1967 eight barrel

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Re: Top End Rebuild Advice
« Reply #12 on: October 23, 2019, 01:30:52 AM »
The headgaskets most of us who build FE's use are the Felpro 1020.   They're about 86.00 for the pair. They are .041 compressed.
The chances of a valve being bent isn't likely either unless when the engine was started after 15 years it stuck open and made contact with the piston. That I have seen. Your builder and his choices are poor and as I stated. Low performance poor stock replacements.
« Last Edit: October 24, 2019, 12:58:51 AM by 1967 eight barrel »

pbf777

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Re: Top End Rebuild Advice
« Reply #13 on: October 23, 2019, 01:29:50 PM »
     Yes, the Fel-Pro #1020 gasket is popular, and I do use them, along with others over the decades (some of which are no longer available), but I have concluded that this may not be the wise decision. 

      The Ford FE engine was designed originally to utilize a steel shim gasket, and these generally worked well in the original assembly until corrosion may cause a leakage scenario, but then probably due to the lack of proper preparation of the mating surfaces, replacements proved problematic.  The advent of the the softer, more compliant composite material gaskets proved more reliable and popular, particularly in the rebuilding cycle(s).

      Unfortunately, these softer, thicker, more forgiving material gaskets providing better sealing on particularly less than ideal surfaces, tender the negative result of causing greater distortion of the casting components as they are displaced under the clamping loads applied as the retention fasteners are torqued, and the variables created by the expansion and contraction with temperature change.  This effect is compounded as one transitions from the "rebuilder" type to the "racing" type gaskets as along with the "fire-ring" present in the first, the later adds a "combustion sealing ring" of a "pre-flatten steel wire" which is intended to support and increase the clamping load on the "fire-ring" to further aid in the prevention of combustion sealing failure.         ???

     Sounds good, but this accentuates the distortion upon the castings, and when coupled with the substitution of ARP fasteners, particularly studs, with their increased clamping force, at times to the point of failure.  One may witness these failures as cracks about block bolt holes usually migrating to the nearby water passage voids on the decks;  the cylinder heads exhibiting cracks emanating from the deck face to bolt hole juncture following outward to exhaust face and then up the bolt post, this failure being more prone to the shorter head retention fastener positions do to the reduction of elasticity vs. the longer fastener, and reduction of material thickness due to the exhaust face machining, and I have witnessed it most often at the center bolt hole.  In one instance, we had a 427 on the dyno, after completion of the session, on cool-down, I'm standing next to the engine in the process of dismounting it, and I hear a loud crack; I immediately recognized it, and began the search, a crack on the outside of the block between cylinders one and two at the base of the head bolt boss running horizontally about three inches with water leaking!        :o

      Conclusion: With these observations and experiences, we have chosen to use the MLS type gaskets, if the surfaces permit, as they demonstrate far less of this described distortion, and hopefully fewer of said related events.         ;)

      Now the disclaimer: No, they are not concours correct!      ::)

     Scott.
« Last Edit: October 23, 2019, 01:33:47 PM by pbf777 »

1967 eight barrel

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Re: Top End Rebuild Advice
« Reply #14 on: October 24, 2019, 01:06:36 AM »
If you talk to the four FE builders most commonly known they are not using MLS gaskets. They are far too picky about surface finish. Brent, Blair, Brown and Robotnic are fans of the 1020. I have never had one leak. I don't use studs for the reason alone that it makes it all but impossible to remove a head in a shock tower car. I do use ARP bolts with the same torque specifications as Ford required. No one uses steel shim anymore. Not even for a stock rebuild. They are just too prone to compromised coolant and oil leakage.