Hi,
Very good. I agree with your thought on what’s occurring, I’ll detail why. Good precautionary, avoiding Ethylene Glycol’s devastating affects on your bearings.
INTAKE INSTALL ONLY:
On SBF/BBF motor’s, early SBC’s, in addition to using (2) small topside gasket dab(s) of Hi Tack-one in front, one in the rear so gaskets don’t shift, I’ll use a continuous bead of permatex on both sides of 1262’s gasket’s coolant passages, (1) on the head side, (1) on the intake.
Additionally, I was suggesting a very light skim coat to cover up the moderate pitting you’d mentioned of the lower (Corrosion based-?) you previously described to/in addition to the beads around the lower intake to head coolant passages. between intake ports Now, method to avoid much of this...
HEADS INSTALL BEFORE INTAKE:
New heads. Before torquing the heads, you can grab all the intake bolts with the gasket(s) installed, intake bolts finger tight with an additional 5 Ft/lbs in proper sequence with a torque wrench minimizes head creep while they're being torqued down.
The real issue is the head locators doubling as Dowels.
OE’s (2) split pin’s leave quite a bit of slack for creep. The bolts taper up top to bring things in clos-er, studs are the best, but don’t have that same effect.
I’ll run these on most street motors, they really help. Full hollow pins, light taps with a soft hammer & they’re in.
https://www.summitracing.com/parts/tfs-51400420
After your (1st) torque pass of (3) head steps of torquing, back off the intake bolts will avoid interfering with your head torque numbers as little as possible can & do shift significantly, but not after your 1st pass.
Have learned over the years, the 1250’s work better for you than 1262’s.
Snip out the coolant passage crosscorner gasket section.
The Intake & head need be free of all old gasket material, debris, hospital clean surfaces and then torquing the lower needs to be done in the correct center- out crisscross sequence in stages. N.P., will post if you need it..
I’m pretty certain you don’t bother with the cork lower to block gaskets & use a good bead of Permatex. No idea why they even include them, lol.
The printoseal’s are good gaskets but certain (like 1262’s) are purposed as full Competition gaskets, suitable for a motor that’s Blueprinted, with frequent tear downs & higher accuracies.
Their surface area is slim, with a very square race motor they’re great with large port heads (note coverage around the coolant passages is small vs 1250 Gaskets). Not my choice unless I have a motor disassembled in the shop, and dead on alignment on between heads, block, intake is a breeze.
If I see error in a valuable intake, I’ll opt for a known square surface and a >/=32RMS finish value and mill 0.300 off each side and drop 0.25 intake spacers in both vs “making it work with Permatex”. I don’t much like that, to be clear, wrong approach, but things in the real world aren’t always so accurate, it works reliably, done neatly and Permatex remains pliable, shifting with engine’s heat cycles.
What head’s are you running, TrickFlow 170’s, AFR’s?
I hope this helps, not the first I’ve seen & causes lots of headaches.. Laying the intake down & bolting lightly to one head, light behind the motor & looking across it will help gauge things. The OE Ford steel core (Black) gaskets also work well, if lined up tight.
Good luck!
John
**I began drilling 289-460’s decks with (3) 3/8” holes, reaming +.0002 for dowels for a light press if an aftermarket block, protruding 3/16”, heads the same +0.011 over. I’ll only do the block’s holes on a Mill, but made a jig with Tungsten inserts & locators for aligning the holes in the heads with a W letter drill (0.386) to keep alignment tight. Also lines up to cut the required head gasket openings.
That works every time.
