The only way to tell for sure is to have the block sonic tested. If I remember correctly, an "X" marked block would be a good canidate for this process.

This process uses ultarsound to meaure the thickness of the cylinder walls. It is not fool proof though.

I had a C6ME-A block that when sonic'd, didn't have enough metal on two cylinders to go thirty over. However, on the average, most 390 blocks can go to sixty over.

For performance use, the machinest I use does not recommend a wall thichness less than .011 on a thrust side. Obviously though, the more wall thickness, the better.

I'd be taking the other 390 block to the machine shop for professional advice. I am not a machinest by any means. The question to ask is how did that scratch get there? And, what am I going to do to keep that from happening in anything that I build?

Well, time to pop all my morning pills. Good luck with your project!

Tim Johnson aka oldgoofydude

I had a 390 block with the "X". It was not a thick wall block suitable for over-boring to a 428. I seem to remember reading that the "X" indicated a higher nickel content which is good.

As far as the vertical scratch goes, asking a machinist isn't always a good idea. He will usually only give you one answer which is the "right" answer, but without any consideration of $$. I think I would ask him to ball-hone that one cylinder only and then inspect it yourself and consult with him at that point. Sometimes the "fingernail" scratch test isn't accurate and the metal displaced by the scratch can make it feel worse than it really is. If after honing, the scratch is gone or only slightly visible with no "fingernails" catching, it is probably all right. It always seems a shame to go for the rebore over something like this. I had a similar question due to a little etching from coolant due to a blown head gasket. The consensus here was to try it. And I will. Will only be out a bit of $$ on gaskets if it's not OK.

n/m

#2...copper is fine, but you should have put gasket shellac on it.

#1...I'd replace the intake, BUT any radiator stop leak crud will work great on a crack like that. there even used to be product called "Engine Weld" that was great for a cracked block....in a $50 car...chuckle, but it did work. Radiator Leak products can often plug up a radiator, especially if it is already partilly plugged. If you use something like this, use it until the leak stops, then drain the rad and refill with clean water and anti-freeze. By the way, cast iron is usually welded after first heating the casting up in an oven, so it can't be done in the car. It is a specialty practise with often uncertain results.

just from my experiences...throw the end cork gaskets as far as possible when you open the intake gasket set. I use a bead of silicone front and back, always. Also put a thin wiping of silicone around the water ports on both sides of the intake gaskets. This helps with pitted port areas that always happen around the water jacket ports.

a leak like this is easy to repair if you keep the right perspective. first you need to find the end of the crack and use a special screw that you can buy to stop the crack. you but them at any GOOD auto parts store, not kragens or schucks. you drill a hole and the special screw goes in to lock the end of the crack. after i do that i cut a mild groove along the crack and then braze it. use the torch to keep the metal warm as it cools so it does not cool too fast. use a grinder to dress the brass to match the surounding area. after it is cooled use a tap to chase the threads for the fitting. after all of this is done, repaint and use it. the perspective i like to give on a repair like this is the fact that the manifold will never get over about 300 degrees no matter what, brass sticks well and doesn't melt at that temp, and it is only subject to 20 pounds of pressure maximum. if a brass radiator can hold together with just solder then a brazed crack in an intake water passage will last until the earth has cooled to ice. hawkrod

Two days with the Marine-Tex and it seems to be holding. I ran it up to operating temperature a few times and no leaks.
I don't really know what this stuff is made from but it's a heavy grey paste with a clear yellow gel activator (nasty stuff!). 5 to 1 mix and about 6 hours later it sets like stone. File, sand, paint and you're done.
This should hold me until I decide to swap out the intake again. :-/
Thanks again,
Sam

I suspect a rear oil plug is leaking.

Is the bent pushrod on the end of the rockershaft?

Shoe.

If you did lose a press-in plug, you should have also noticed a significant drop in oil pressure, which you didn't mention. If you did have a drop in pressure, and you use hydraulic lifters, one could have collapsed and the pushrod could bend with the excessive lash or even pop out of the rocker and bend. Still, the last main bearing cap can be a little devil what with all the silicone and rubber sticks and nails, etc. And very difficult to change in the car. Are you sure you got it done right? Did the machine shop refinish the crank where the seal goes? Maybe the diameter is too small now. Or maybe there is rust on it that destroys the sealing edge of the seal (which should pint to the front of the engine). On the small blocks, there was sometimes a metal pin to help hold the old fashioned rope seal. This had to be removed when changing to a rubber seal. Something to look for. Oh, and the only time I ever bent a pushrod, it was my own fault during disassembly...don't even ask. Could your engine builder have done this? Let us know what you find out.

On the bent pushrod situation, do you know if the engine was assembled with the crank in the correct position? The crankshaft pully has an "X" position that must be aligned with the pointer before torqueing the rocker shaft bolts. This is a position that has no load on the valve springs. If the springs are loaded while torqueing, you might get a false torque and possible rocker shaft breakage - especially the end lifters.

On a block dated from the later 60s, it's most likely a 428. Since it has a 361/391 bore, yours is usual.

Still, the forums have so far only found "trends" in the markings, and not hard rules. As long as a 15/64" drill bit will not fit between the cylinders at any reachable location from the six core holes, you've likely got a solid starting point. A sonic map will tell you for sure.

Shoe.

the centerline of the crank is a little lower so the trans crossmember hangs a little lower to keep the back of the trans pointing in the right direction. hawkrod

here is one to look at; http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1858801356&rd=1

It sounds like you really don't have any oil pressure. It may be one of the press-in plugs became dislodged. Or, one of the cam retaining bolts became loose. Remember that with a drill, the dist is not installed and you will lose some oil pressure around the feed for the dist lubrication. It doesn't take much oil pressure to keep bearings alive if you aren't hard on the engine, so you may have caught things in time to avoid a lot of $$. I suspect that you have the dubious pleasure of dismantling things till you find a problem. Personally I suspect a cam retaining plate bolt has loosened. that could even be the tick you heard...hitting on the large sprocket, or probably a lifer as the oil pressure is actually low. "Intermittent" sounds like a screw loose vs a plug coming out. With the pan off and a mini-light (one of those ones on the end of a thin flexible shaft), you can see up there to check, or take the front cover off. Sounds like you have a bit of elbow grease ahead of you, but no major pain money-wise except gaskets.

Pulled the intake and everything was fine. Used the drill and could hear oil gurgling out near the front of the engine some of the time. Pressure varied from 0 to 38 pounds with a low of 8 pounds common and an average of about 28 pounds, but again sometimes there was no pressure at all. (Noted I blocked the holes to the rocker arms shafts.)

Pulled the timing chain cover and everything was correct there also. Ran the pressure check and no sign of a leak and again the oil pressure varied widely.

I had another 390 engine on an engine stand that has been recently rebuilt so I pulled the distributor installed the gauge and used the drill to find out what the pressure should be if
everything was OK. Got 68 pounds in just a second or two compared to the 20 seconds it took to get 18 pounds on the problem one. It took about a minute to get oil to come out around the rocker arms and the pressure was very steady.

Went back to the problem engine and it took about a minute before the gauge moved.

I'll pull the engine out next weekend I guess.

Don't know of any "S" manifolds before '66. It's iron right? 406 and 427 manifolds are alum. The "S" was used on the regular engines too, not just the GTs.

The "S" intake was available in either 2-barrel or 4-barrel form. The two are identical except for the carb flange.

There is also the large thermostat and small thermostat variation of the "S" intake.

It was used most often on cars from 1966-1971, but some pickups have been seen with them. Pickup trucks more often got the "T" design.

Though it was used on the 390GT, it's not a performance intake, just a smooth running luxury liner hauler. Obviously, it's quite a common intake.

Shoe.

1966 - 67 352, 390, 410 or 428
Valves 2.02 intake, 1.55 exhaust.
Standard FE heads for the time.

Royce Peterson

The C7ME block is useless info. These block markings do not indicate anything except it was cast fbetween 1967 and about 1972 - it could be anything, from 330 to 428, including a sideoiler 427. I'm suspecting it's an overbored 352/360/390 block.

There were no special performance 390 rods made from the time C6 rods were forged. Hell, it's the rods that defined the SCJ in the first place and they would have to be LeMans type, not C6AE-C rods.

1U crank is not an SCJ crank. The SCJ crank is balanced differently than other 410/428 cranks and generally got the 1UA marking.

The SCJ did not get special heads. It got standard CJ heads.

Avoid this auction like the plague. There are plenty more surprises once should you win it, an none will be good.

You can do better on the price if you look, too.

Shoe.

n/m

Randy Deliseo in currently the high bidder. If he is in on the deal, you might look at it and ask the seller some questions. Those date codes are hard to find.

Here's a few thoughts from my painpill laced mind that might be useful.

The CJ and SCJ blocks have a "C" etched at the back of the block. It looks like somebody took a nail and scribbled it in by hand. Standard 428 blocks have a sloppy "H" on the back.

Ask the seller to send you a picture of the back of the block so you can see if it has this etch or not.

BEWARE though! Real scumball scammers have been known to take metal filings from the same casting, mix them with clear epoxy, and make false letters and numbers. Then they can be either painted over or dirtied up tp hide the forgery

If you can physically inspect the part, ask to scrap the casting numbers with a pocket knife. The epoxy will peel, real cast in numbers obviously won't. A scammer will definately object to this. An honest seller might object until you tell him that you are just protecting your investment.

If you it looks funney and you aren't allowed to check, walk away.

Standard CJ's had C7AE-B rod casting that had been drilled out to accept a 13/32" rod bolt. Take a 9/16" socket to check as the standard 390 rod bolt uses a 9/16" nut.

As Shoe stated, C6AE-C rods are a standard production rod. Nothing special. The SCJ used cap screw rods with the casting number C6AE-E.

The SCJ engine, because of it's heavier rods and pistons used a crankshaft spacer with a counter balance cast in that looks like a hatchet. No hatchet counter balance, no SCJ as far as I'm concerned.

As Shoe mentioned the SCJ had a unique crankshaft.

You would do well to listen to Shoe's advice on this one.

Gotta run! Hope this helps!

Tim Johnson

On a business trip to Lyons, NY, I visited Delisio's shop. He won the auction in question. He needed the heads for an early project and the block for a 68 lightweight Mustang restoration. The first 50 were built on December 20, 1967. The date code on the block in the auction was L20 which would be correct for the car. The first 50 CJ Mustang Lightweights had regular passenge car blocks and C8AE 6090 J heads . Delisio has done 8 of the original 50. I saw the engine and it was CJ heads and 4V low riser intake. Just in case you were interested. John