4.2 head gasket

Randy,

The 4.2 multi-layered gaskets are made by Felpro. The last couple of sets Chris bought were from a source other than the Ford dealer using a Felpro part #.

Since these gaskets are now being advertised in various car magazines like Car Craft as being used on NASCAR engines and being avalible for many Chevy and Ford applications, you may be able to purchase them from Autozone or some of the other major chain stores.

I would not reccomend using them unless you have a freshly decked block and heads (the smoother the better). Without a very flat and smooth surface they will leak compression into the coolant passages under boost.

David
 
David thanks.

My head gaskets are going out.So I have been kicking around
what options I have.Since I know that I will abuse the SC I thought
that I would go with the 4.2 gaskets.

I don't need to do the bottom end on the SC . I have no anti freeze
in the bottom end.So I don't know about if the finish on the block deck
would be good enough for the 4.2 gasket.I am going to just replace
the gasket.

But if i would need to pull the block out to get the deck surfaced .
I think i would just go ahead and build the motor up.

I can't make my mind up to keep it at the h.p. I have or go all out.
I realy don't plan on doing any racing with it,other than entertaining
myself on the county black tops.I might enter a race and make a couple
passes now and then, go to the bleacher and party with others.I will still
race but I never finish the races any more.just like the atmosphere of being
there.
 
Randy,

In order to properly deck a block for both trueness and finish, you'd have to pull the engine and have it disassembled. If you are not at the stage where this is an option for you, then just replace the gaskets with standard Fel-Pro composites, and use ARP studs this time.

I use the 4.2L gaskets currently, and the only way they will seal is with a mirror finish on the heads, and a VERY smooth block finish. Otherwise, you WILL get leakage, like Dave mentioned.

If I were you, and you aren't planning any major modifications, just get the heads refinished, and use the gaskets and fastners I mentioned. You'll be fine with those.
 
I am not looking to throw a wrench in the works. And Bill, Sean was telling me about what happened with your gaskets the first time around. .. I just wanted to note that I was fortunate with the 4.2's. I used a set of Ford bolts and only had the heads milled & it sealed fine. I raced that thing every time I was in it & didn't have a problem. Perhaps my block was in good enough shape in order to seal properly, I don't know. All I did was cookie the block after taking the heads off so it looked clean. So don't take this as stone. As Bill & Dave can attest that one side not properly finished could cause havock.

I just wanted to let everyone know that it still is possible to use and benefit from the 4.2's without taking the block out and finishing it. In fact, my block gave up before the gaskets did. Blew a rod. However, while disassembling the old block, I (being cheap) kept thinking, I could reuse these, they look great! ;)

So what the heck, throw caution into the wind, use the 4.2's and whatever bolts you want (Ford's work fine). Worst case scenario, you spend 4 or 5 hours replacing the gaskets if it doesn't hold.

I still do agree with someone that said finishing head & block with 4.2's & ARP's makes it "Bullett Proof"

Anthony
 
Anthony,

My goal is only to send someone in the "best" direction, albeit your suggestion is still the "right" direction. Although some of us have become quite experienced replacing head gaskets on a regular basis, not everyone wants to experience these reliability issues if they can avoid it. It is always best to try and avoid the trial and error process if possible, as it makes working on the vehicle, and owning it in general, more enjoyable.

Although you were lucky with your block suface being free of manufacturer's defect, a lot of the 3.8L blocks do have block surface issues that should be resolved through the decking process. With the power you're making, I think it's fair to say that you're lucky if you are running stock bolts and a factory block without leakage issues, from either the trueness of the surface, or the head lifting slightly under boost.

As for re-using the gaskets, that's not something I would recommend to others either. Although the gaskets look fine when they come out, they still go through a crushing process when the heads are torqued down, and should not be re-used. Again, just because one person has success with it, doesn't mean that everyone should, or will be so fortunate. Chris Wise had been in contact with Fel-Pro regarding these gaskets when he started using them, and I believe they told him not to re-use them.

There is no point sending someone down the path to failure. These cars are not worth taking shortcuts with.
 
Well maybe i should list my mods.I have most of the bolt on MP has to
offer.I am making 250RWHP.My SC has 91,000 miles on the speedo.
.When I take the heads off I plan to clean the bowl area up.
With a serdi cut. And gasket match.I have a flow bench,welder,
if i want to go farther with the heads.

I am tempted to build for the fastest sc,for the shoot out at ST LOUIS.
Connie would be the pilot.

I would like to go all out on the rebuild , .I would want
to make 500+rwhp I don't know where to get some of the machine
work done.I would want to have the cam bearing line bored for torrington
bearings. And do rods,cam,my style roller lifters & pushrods, ect.
.And if I would go that far I would want it done in the next 30 to 45 days.
But I do not think the crank would hold up.

The mods i have now are.
C&L 76MM
MP cold air tube
BBK 75 mm throttle body
MP plenum with some porting
MPII blower
MP 3/4 raised top ported
#42 injectors
intake manifold plenum ported
SCP exhaust with cats

motor is stock, and the head gasket was blown on the last dyno run of the 250.7 rwhp


Anthony,Bill M,David N. & gldiii. Should I go for it. What do you all think?
 
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Should I go for it What do you all think?

Randy,

You know what they say.....Misery loves company.

I say go for it.

David

PS: If going that far, you may want to contact Fred H. for info on the 4.3 billet crank he has in his latest engine. It should be strong enough to handle the power your after.
 
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Randy,

I'm with Dave as far as encouraging you to move forward with your project, as I do think you have enough time before the end of September to put something together.

As for getting in done in 4-6 weeks, that seems impossible. Try finding a machine shop willing to drop everything they're doing just for you....it ain't easy.

You still have to research what components you want, buy/order EVERYTHING you will need etc. Expect to spend 25% than your highest estimate, and see if you can still afford to move forward.

Then....GO FOR IT! You'd have to start immediately.
 
Randy I have to agree with Dave... Go for it man!

I don't believe we've seen 500rwhp but it may not be unobtainable. Also as Dave mentioned, if the crank is a concern as it very well could be a concern, Dr. Fred has a very nice (expensive) crank that could two SC's on top of it if balanced correctly! ... Costly, but very worth it for your goals.

Randy I'm also interested in the list of bolt-on's you will be using to obtain this. Let us know.

And Bill,
However, while disassembling the old block, I (being cheap) kept thinking, I could reuse these, they look great!
If you took that serious about reusing gaskets, please place the wrench down & step away from the vehicle!! ... ::hint hint ";) "::

Anthony
 
Bill M. I own a machine shop.And I would be willing to drop every thing to pursue
this build up.If I deside to do it.But I do not have all the tooling to do all the jobs.
Such as line boring the cam shaft bearing,to install torrington needle bearings,for
the cam to ride in.

I can do the decking of the block,boreing cylinders,and all the head work.

SilverCasket ,Well the bolt ons would be the same bolt ons every one has
or could get.I e-mail DR.Fred today as David N. brought up the billet crank shaft.
He has not got back yet with the me to say if he has a billet 4.3 crank.That would
be a must for me to start.As I do not feel the stock crank would hold.Be cause if
I would build the motor up and did not come up with the HP number.I would
switch to a differrent fuel to get the HP number.
As what I would do differrent in parts.I would install larger dia.head studs, ARP.
The motor would have to be machined to except roller bearings.The valve train
I would start with titanium roller lifters,then put carbonfiber pushrods on them.
I would go with titanium valves, & collars.Try to lightin every part I can.I do have
carboncarbon brake rotors but i beleive they would be a waist on this project.
My back ground is building parts for 800+ HP nitro Harley davidsons.I don't know
a lot about the SC.So I may not be able to meet the goals of 500HP.
I will kick the idea around till the end of the week,talk to some people
and see what is possible and what isn't.I will get some numbers together
and run them through a program i have and see how much air I will need
the heads to flow at.And what type cam profile I will need.
I talk to Stiegemeier this afternoon ,he said it would take $15,000.00 to do it.
That is a lot of money just to win a trophy,at one race.And all I need is to just replace
the head gaskets.I would be better of just slipping a SVO crate motor in that would
make 600hp and it would be half the money.Then put a blower on it if it didn't have
the horse.

RANDY
 
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Enough said then !! Sounds like a good plan to me.. In fact Randy, that 15k Steg mentioned could be possible being you will be completing most of the work. And only needing to do it all once. I've put that much in just in the last 8 months. But that was going with all the bolt ons and then a new bottom end & the heads/cam combo. A few other things of course. If I had to do it again, I don't even think I could trim that number down. And that was with me doing all the work.

There isn't too much I can help with on the maching end for you. But if you stick with the 3.8, go with more air on your intake. I think you said you have all the MP bolt ons. Also look into the 90mafs from Ford.

Sounds like you have a good idea what your looking for.

Good Luck,
Anthony
 
After checking into some parts that I would want to use.I have found
that a better crank is not avalible.It sounds like a billet crank would take
two month or longer to get.If it takes that long they do not excist,

So i am back to just replacing the head gasket,and leaving the motor
stock.After adding the parts I can't get, and the price of the parts that I can buy.
The horse power to dollar power are not there.

If I would mod the SC any more it would be with a 600hp crate motor
from ford and then I would supercharge it.For half the price of a sc
build up that wouldn't run but about 300 miles at a time.And I would
have three times the power with a blown crate motor.

THANK FOR THE HELP ALL RANDY BAKER
 
Maybe next time

It was fun to imagine a 500rwhp SC while it lasted.

Hope it goes well Randy. Talk to you soon,
Anthony
 
SilverCasket,I still would like to do it,but my time line is short.
And some of the SC vendors that I made contact with, don't have
the time.Or parts in stock.

RANDY
 
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I need to fine me another SC engine.So I can take my time and
build it up.

I was reading in a earler thread from our neighbors up north
about installing 4.2 head gaskets.They had used copper spray
sealer to seal 4.2 head gaskets.I haven't found any info if
this was successful.

If I would refinish the head deck.And would use some of the old
shellac brown sealer. If that would work on the block ,to seal the
head gasket?

I havent had hands on look at the 4.2 head gasket.It should have
a crush fire ring for sealing.So the part that will leak is around the
water or oil passages.Would there be room to recess the water &
oil passages in the heads to install rubber o-ring in the heads.So
I wouldn't have a problem with weap leakage,when the aluminum
heads cool down?

Is that the problem with the 4.2 head gasket seal,weapage of anti-
freeze,But the fire ring will seal just fine?
 
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Is that the problem with the 4.2 head gasket seal,weapage of anti-freeze,But the fire ring will seal just fine?

Randy,

The ones that I have seen leaked at the combustion ring and into the coolant passages. There is no leaking into oil passages. Here is a picture of the head that leaked on my first set of these gaskets. It leaked in an area that had a slight amount of pitting (dark spots far right). I found out later that the heads were not decked after porting. We took them to a local machine shop and 3 hours later we were putting the car back together, and they haven't leaked since.


leak.jpg



When the 4.2 multi-layer gaskets leak, it only happens under max boost (dyno or track) and really isn't something you would know was happening if not for overflowing the coolant tank at the track. When the engine cools the coolant would be sucked back into the radiator and the tank would empty back to normal levels. It never leaked or weeped like copper gaskets. I drove mine for about two months before figuring out it was leaking.

We changed the gaskets on Chris' engine about 4 times before figuring out that the deck of his block was slightly warped (IMO, from overheating ) and the gaskets even with 1/2 studs and sealing spray, would not last more than a week before they started leaking. He found out they were warped when he sent the block to be tested for leaks. Once the block was decked the leaks stopped.

My block is not machined super smooth and has slight milling cutter serations that apparently will seal without using copper spray, but if doing another engine I would get the deck and heads as smooth as glass to insure a good seal.

David
 
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David N. My head gasket are not blown.but they leak at full boost.
I first notice it on mine, when on my way to my last dyno tune. And
during the last dyno tune.the coolant tank would fill up.And that may
be were my 20hp was that i didn't see on the dyno sheet.

I am just looking for the stongest way to fix it .With out taking the
block out,till this winter.Be cause I am kicking around trying to add
more volume of air.But not much more in boost.With the stock internal
SC motor.Test the junk parts i have ,and a couple idea. before spending more money.

Thanks for the picture I see that one idea I had will not work.

Randy
 
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