Unhappy Ford Bronco wants GT40 heads

   #1  

CZLoco

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Someone buy my $250 Dell gift card for $200. Black Friday is coming up soon and you know you'll use it on a new laptop or big screen TV!

Someone else find me some GT40 heads for $100 that I can get machined.

Thanks in advance. :D

I fucked up and added a bunch of "cold" water to a warmed-up, running 351W's radiator in my Bronco while the thermostat was open. Now I've got white smoke coming out the tailpipe.

Compression on all eight cylinders is between 155-163, so that's nice.
I added green dye to the radiator water (no coolant in it) and didn't see anything leaking externally.
Just a very slight trace coming out the tailpipe.

Radiator compression test passed with flying colors.
I did notice a leakage at my water-inlet housing, so the Bronco gets a new housing & thermostat soon. Maybe even a new water pump while I'm in there.

She runs smooth & strong still!
So whatever it is, it's a VERY SLIGHT issue.
Head gasket maybe. Cracked head maybe. IDK.

The plan is to limp her along and keep an eye on temps & coolant level until I can afford to swap out the heads.
Not interested in rebuilding my current heads because first, it'll take a couple-three weeks for any machine shop to fix it. And if a head is cracked, I'm down for even longer while I find a replacement.

I'd rather just pick up a set of used heads, get them machined up.
And then swap everything out in one weekend in my driveway.

Can't afford fancy heads till next year.
I hope to eventually do a 408 stroker with goals of ~500HP and 500TQ, somewhere around there.

A set of cast iron GT40 heads will work out great now AND later.
So that's kinda what I have my eye on.
GT40P is a no-go due to needing special headers and I love my current ceramic coated long-tube headers.
 
   #3  

Vegas12

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Take this FWIW.

Standard headers WILL work with P heads, I have done it.

The plug placement makes it tough, but not impossible. ....you cannot use a regular spark plug socket and ratchet.

Just cut a spark plug socket in half and grind flat spots to be able to use an open end wrench on it....3/4" if memory serves.

You'll also need some asbestos boots to keep the plug wires off the headers.

So don't be afraid of P heads and because of their use on Explorers before the 4.6, they're plentiful.
 
   #4  

Vegas12

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Oh, and P heads aren't threaded for the thermoactor(?) hard lines in the back.
 
   #5  

BigGar

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Just as likely your block is cracked, but hey. Do a run of Blue Devil and it will likely fix any minor head gasket leak. The shit is pretty legit. If you ran a pressure check and it passed, then you probably don't have a problem. I dunno. Do you have a radiator pressure test kit? If you pressurize it and there's a combustion chamber leak, it would probably put a good amount into a cylinder and then you'd really notice steam upon startup, unless you hydrolock the engine and bend a rod :)
Either way, I'm not optimistic!
 
   #6  

Snail

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Eddie, try ceramic engine block and head sealer, Moroso is the brand I used to seal a 327 block, it worked.
 
   #7  

Snail

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The big guy got in ahead of me.
 
   #8  

BigGar

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Eddie, try ceramic engine block and head sealer, Moroso is the brand I used to seal a 327 block, it worked.
I've never seen the Moroso branded stuff. I've used a couple others, like the aforementioned Blue Devil with decent results.
 
   #9  

Bandit Man

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Are you sure its not just condensation? Are you just fishing for a reason to change the heads?
 
   #10  
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CZLoco

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Are you sure its not just condensation? Are you just fishing for a reason to change the heads?
Could be partly fishing.
But no, this is beyond condensation.
The green dye coming out the tailpipe, even though it's very slight, is proof the coolant is getting into the combustion chamber. :([

Btw, yes I did pressurize the radiator. It passed with flying colors.
 
   #11  
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CZLoco

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That Blue Devil sealer has been recommended a couple times now.
I thought liquid sealers were the devil (pun intended) for engines.
 
   #13  
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CZLoco

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Can't afford bottom end till the 408 stroker next year.
 
   #15  

Zippy

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...stop putting money into that lump and save for a good engine...

...stop drinking for a while and save the $$$ you spend on booze for a good engine...

...buy one half of the amount of food you eat now and eat in more often...save the $$$ for a good engine...
 
   #17  

Rocco

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Starting from cold with the radiator cap off as the engine heats, look for tiny gas bubbles in the coolant that will confirm a bad gasket or crack. Try draining your oil into a clean pan and look for traces of that dye you added.
 
   #23  

LE05BUSA

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The problem is Ford, in their infinite wisdom, has different bell housing bolt patterns between the 351 and 460.....they even changed the bolt pattern on the mod motors where they don't match either series.
Not all...
 
   #24  

Vegas12

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The only one I can recall was there was 1 bastard 400 that had the small (windsor) bell housing pattern.....not a popular motor. Which is funny because the 351C had the small pattern and the 351M/400 had the big block pattern....and they were all the same series of motors.

And there are baby (small block) C6 transmissions.
 
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   #25  
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CZLoco

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Run a leak down on it. That will offer a little more info than a compression test will
You know, I was gonna just for the heck of it but couldn't find a way to put oil in the cylinders without making a mess. I shoulda just done it anyway before I put it all back together. But figured the dry test good results made the wet test irrelevenat.

Does the coolant pass thru the intake manifold on that lump?
Yep!

Starting from cold with the radiator cap off as the engine heats, look for tiny gas bubbles in the coolant that will confirm a bad gasket or crack. Try draining your oil into a clean pan and look for traces of that dye you added.
No bubbles! No milk on the oil or tranny dipsticks.
Good idea about draining the oil and checking for dye!!!

I have a tool that detects combustion gasses in the cooling system. It is like this on, but $nap On brand.

FIT Combustion Gas Leak Detector Cooling System Tester Co2 Checking in Radiator | eBay
I've got the cheaper tool, called the "Block Tester".
If the fluid in the tool changes from blue to yellow, that means you have Co2 in the radiator. If it turns from blue to green, then you have "trace amounts of Co2". Or just leftover gasses from a random leak. Mine was green. Not the full blown yellow.


DUDE!
He posted on FB also and I messaged him yesterday about it.
No response yet. :fu:
Thanks for the link. :up:
 
   #26  
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CZLoco

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Hey, I can't afford to get new heads or even have mine rebuilt right now, so ya'll need to get over this long-block suggestion thing :D
Someone buy my dang Dell gift certificate already.
That'll pay for gaskets, thermostat & water pump & head bolts & misc. :)
 
   #27  

LE05BUSA

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The only one I can recall was there was 1 bastard 400 that had the small (windsor) bell housing pattern.....not a popular motor. Which is funny because the 351C had the small pattern and the 351M/400 had the big block pattern....and they were all the same series of motors.

And there are baby (small block) C6 transmissions.
'91-'92 4.6 2V (Crown Vic, Grand Marquis, and Lincoln TC) have Windsor/Cleveland bellhousing bolt pattern.

'71-'73 400M has Windsor/Cleveland bellhousing bolt pattern.

I built a few hot 400M's for circle track customers with 351C TRW flat tops, bushed stock rods with ARP bolts, and quench chamber 351C 4V heads with filled intakes and port plates. They can make pretty good power.
 
   #28  
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CZLoco

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Hey, someone on the Bronco forum just mentioned that lower intake manifold leaks are common.

GetBent4x4 said:
Lower intake leak is common on a 351 and the coolant sits in the front valley below the t-stat.
And Google says:

A Coolant leaking internally from the intake manifold gasket or cylinder head gasket can end up in one of two places: mixed with the engine oil or burned with the air-fuel mixture in the exhaust.
Sheeit, if all my issues are from a simple lower intake manifold leak and I don't have to pull the heads yet, that would be sweeet.
 
   #29  
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CZLoco

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I do have that pool of coolant under my thermostat housing.
I assumed it was the housing itself but maybe it's coming from the lower intake manifold.
 
   #30  

Vegas12

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'91-'92 4.6 2V (Crown Vic, Grand Marquis, and Lincoln TC) have Windsor/Cleveland bellhousing bolt pattern.

'71-'73 400M has Windsor/Cleveland bellhousing bolt pattern.

I built a few hot 400M's for circle track customers with 351C TRW flat tops, bushed stock rods with ARP bolts, and quench chamber 351C 4V heads with filled intakes and port plates. They can make pretty good power.

I'd already mentioned the bastard 400's (It's a 400, not 400M) but the vast majority were the 460 pattern.....the 400 was specifically built to replace the 460, until it wasn't. The 351M was the same block as the 400 and they needed the M to distinguish it from the other two 351's.....three 351's if you count the 352 FE (same bore and stroke)

Never heard of the 2 years of MOD motors being small block patterns ...if so, Ford changed it later to it's own pattern.....which makes ZERO sense as usual.

Surprised at the choice of a 400 block for your build....while you get the 4" stroke, the bigger mains and lack of intake manifold choices really hindered those builds compared to a 351.
 
   #31  
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CZLoco

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351 Cleveland big block 351 Winsor small block & 351 M.... small block are the only ones I'd heard of.

Dunno what "M" stands for.
Never heard of a 352.
 
   #32  

Vegas12

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351 Cleveland big block 351 Winsor small block & 351 M.... small block are the only ones I'd heard of.

Dunno what "M" stands for.
Never heard of a 352.
Negative....IF Ford used big block or small block, the Cleveland is 100% small block.(same head bolt pattern, same bell housing, same motor mounts etc.)

Ford goes by series, the general public has made them big or small blocks.(335 series, Windsor, FE, 385 ETC....)


The M stands for Midland, Modified, Mistake.....it depends who you talk to.

The 351M/400 are tall deck Clevelands(335 series) with bigger mains....same main size as Windsors

The 352 is an FE motor....same family as 332, 360, 390, 427, 428.....I'm sure I'm missing a few
 
   #33  

Vegas12

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And the 351M, while you called it a small block, has a TALLER deck, uses the "big block" bell housing and motor mounts vs. the 351C which you mistakingly called a big block.

Won't even get into Ford changing balances and firing orders on the same motors depending on year...

Ford is confusing as FUCK!!
 
   #34  

LE05BUSA

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Price Engineering spacers and you can use any 351C 4V intake, though the old Edelbrock Torquer was always the manifold of choice...ported of course. 3.25 main was ok, provided you didn't spin them much past 6500, which you didn't really need to. A little over 11.5:1 with a fairly aggressive solid flat tappet camshaft would make ~570hp and ~550lb-ft @ 65-6600rpm. A decent package overall and something unlikely to be claimed.
 
   #35  

Vegas12

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Sounds like a decent package....

I have a couple 4 bolt Cleveland blocks that I want to build someday....with the aftermarket heads and stroker kits currently available, it should be a real screamer.
 
   #36  
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CZLoco

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EFI and my only two new intake manifold choices are the $900 Edelbrock or TrickFlow setups.
I'll be doing the Edelbrock "Truck" intake next year.

Cobra 351 GT40 intake and the Lightning 351 intake are the only used performance choices but are even more expensive than the new choices I mentioned above.
 
   #37  

LE05BUSA

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If you are going to do a stroker, buy the Trick Flow upper and lower and convert to mass air at the same time.
 
   #38  

BilletMan

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In my opinion, he should just buy a fresh rebuild and bolt it in......maybe save racing aspirations for something worth racing. That Bronco works really well with its stock engine...
 
   #39  

hagrid

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The front half of the driveline wont handle much more than the OEM power output.
 
   #41  

Snail

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Get a centrifugal blower.
 
   #43  

Snail

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Put the little one on the crank and the big one on the blower so it won't slip the belt and get mo power.
 
   #45  

Snail

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Will a 1987 Ford F250 International diesel engine pop in there? I have a runner.
 
   #46  

Master-Cylinder

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Yes.......it's a 351 Windsor.

The Cleveland (335 series) have the dry manifold.

Well then, I'd look there. I have not only a cooling system pressure tester, but a vacuum tester too. I use
both on a questionable unit.
 
   #49  

sailUSVI

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In my opinion, he should just buy a fresh rebuild and bolt it in......maybe save racing aspirations for something worth racing. That Bronco works really well with its stock engine...
This is a good idea....not wanting to be dream killer but a higher HP engine in a stock drivetrain just doesn’t work very well.
 
   #50  
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CZLoco

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Well if things work out according to "the dream", then the front & rear will get upgraded to 4:10 gears and various better parts, just prior to the engine upgrade. :)
It's all a long ways off still.
I already posted a few months back asking for advice on gearing & lockers & splines & stuff.
Got a great education from ya'll. :up:

For now, I've convinced myself the head gasket & heads are fine.
And I'm gonna see how just replacing the intake gaskets and thermostat housing work out for me.
Will do the water pump at the same time.
Got my parts list all set.

1572889475960.png

The oily looking valve cover gaskets are getting replaced just because I can't stand looking at that filth all over the valve covers.
I'll clean the covers up real good while I have them off.
And take a look at the rocker arms & stuffs.
 
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