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Discussion Starter · #1 ·
Ok

I was putting on my new aluminum heads and tightening the last stud bolt and it tore the threads out of the block, I went and got a heli coil kit, but my quesstion is how far can i drill into the block, and does the width matter? It is the hole that is closest to the back of the motor on the passanger side of the block.

Also, I used a fel pro 1003 head gasket, can i reuse it? I did not start the motor almost has it completly torquued down through.
 

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You will be able to re-use the gasket, just make sure it is reinstalled the same, same side up as now. The head bolt holes on an SBC all go clear through the deck surface and into the water jacket, the deck surface is only about 1/2" thick. You don't have to worry about drilling too far unless you have a 10" long drill bit and you're clueless.

If you can and have the ability/equipment like a drill press or vertical mill, make a tap guide plate out of a piece of 3/8-1/2" or so aluminum or steel plate. Drill and tap the plate with the helicoil tap and use it to keep the tap guided and perpendicular/square to the block face. Makes things alot easier.
 

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Discussion Starter · #3 ·
ericnova72 said:
You will be able to re-use the gasket, just make sure it is reinstalled the same, same side up as now. The head bolt holes on an SBC all go clear through the deck surface and into the water jacket, the deck surface is only about 1/2" thick. You don't have to worry about drilling too far unless you have a 10" long drill bit and you're clueless.

If you can and have the ability/equipment like a drill press or vertical mill, make a tap guide plate out of a piece of 3/8-1/2" or so aluminum or steel plate. Drill and tap the plate with the helicoil tap and use it to keep the tap guided and perpendicular/square to the block face. Makes things alot easier.

So you would not recomend, drilling and tapping it on the engine stand?

Should I just take it to a machine shop?
 

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Discussion Starter · #4 ·
Also on the head gasket, I was using the higher torque specs because I did not use arp's assembly lube, but motor oil (I called arp and they recommended this) I have decided since I pulled out the threads with the higher torque specs that i am going to buy the arp assembly lube so i can run the lower torque specs.

If i reuse the head gasket is there going to be a issue since i will be torqing the heads down with less torque than i did on the first attempt?
 

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You don't use oil OR ARP assembly lube on head bolts, it has to be a sealer because all the bolts thread into the water jacket. Red or Copper RTV silicone, #2 Permatex, White Teflon plumbers paste, or ARP thread sealer . Oil or ARP moly will leak water and should not be used on SBC's.

You can drill and tap on the stand without a problem. Making a guide block if you had the equipment was just a suggestion to help ensure that the hole gets tapped straight. If you need to do it without a guide block, thread two or three head bolts into other holes near the one you are fixing so that you can eyeball along them like a gunsight to ensure you start the tap straight.

The head gasket will be fine as long as the coating doesn't peel when you remove it. It hasn't been heat set yet.

A tip to ensure head gasket seal is to torque them all up, let the engine sit overnight, and then go back through the bolt sequence in order and lossen each one and retorque each one one bolt at a time. If you observe closely, you will find that most of the bolts will now turn another 1/8 turn farther to reach your torque figure because the gasket and bolts "relax overnight. :thumbup:
 

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Discussion Starter · #6 ·
Thanks for the tips, about the oil, arp recommends oil or their lube is used on the nut to stud portion of the stud (i am using as arp stud kit).

Can the tip to see if the head gasket set still work with studs?
 

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Didn't know you had studs so yes, you use oil or ARP moly on the upper end threads. The tip about next day retorque applies whether you are using studs or bolts, it is mostly the gasket that relaxes overnight from the bolt torque. It will be more noticable on the long bolts than the short outer bolts.

If you pull a thread out of the block using studs, it won't matter what lube was used at the upper end, it was still going to pull because the block threads weren't in good enough shape to hold.
 

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pittbull7934 said:
Also on the head gasket, I was using the higher torque specs because I did not use arp's assembly lube, but motor oil (I called arp and they recommended this) I have decided since I pulled out the threads with the higher torque specs that i am going to buy the arp assembly lube so i can run the lower torque specs.

If i reuse the head gasket is there going to be a issue since i will be torqing the heads down with less torque than i did on the first attempt?
ARP steered you wrong, their lube and oil should be torqued the same spec as oil, but the Chevy has a lot of bolts that pass into the cooling jacket, they need a sealer not just lube. I and bunches of other guys use plane old Teflon plumbers pipe joint paste with factory torque specs on the head bolts, this insures coolant doesn't get up the threads causing corrosion in the threads if not leakage from the bolt head. Remember to lube under the bolt head or if using hardened washers under the washer as well.

The general problem with torque specs is it's a secondary means of measurement about what you're trying to accomplish. Your trying to take the fastener to the edge of it's yield point which is intended to insure that the clamping load on the fastener is greater than the working load of the parts it's holding together, otherwise the fastener will back out and loosen its clamping force. Torque is a measure of the force required to get the fastener into this plastic deformation state and is arrived at by testing how much force needs to be applied to stretch the bolt into its yield curve. Unfortunately, torque is also a measure of those things that affect friction between the threads of the fastened and the fastener, so condition, cleanliness, and quality of the threads count, as does lubrication. Also the friction that develops between the seating surface of its head and the item being clamped, so lube needs to also be under the head of the bolt or nut being used. So torque can vary all over the place compared to the actual forces trying to stretch the bolt.

One of the problems you get into with high strength fasteners is that the OEM engineers design the fastener they use to fail before the threads in expensive items like engine blocks. When you go to aftermarket fasteners, you will find them to be stronger than the material they are threading into, so when an over force event happens it's items like the engine block that fail before the fastener. In my opinion, unless your building a race engine that needs to take all the potential strength the castings have, the use of extra strong fasteners for non racing applications is a lot like spitting into the wind, eventually you're going to be left with a good but relatively inexpensive to purchase bolt and an expensive to repair or replace busted casting.

Bogie
 

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Good point on fastener strength, Bogie. I use the factory small head pre-sealer'ed bolts on every SBC I can (EVEN 700 hp nitrous sniffers) and try to steer others the same way after seeing results of head bolt stretch tests and clamp load . Studs just aren't worth the money when installed in stock blocks.
 

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19.95QUOTE=pittbull7934]I Don't have any head bolts, the studs came with the motor. Can you recommend a good set of head bolts?[/QUOTE]

No need to replace the studs since you already have them, it isn't that big an issue, just not really worth paying extra for on most engines. Your bolt hole would have stripped even with bolts more then likely, it is a fairly common occurence with blocks that are now 20-30+ years old and bolts threaded into water jackets.

If you want the bolts, www.competitionproducts.com Part # HB8201 $19.95/set for both heads(34 pcs)pre sealed with built-in underhead washer, 1/2" wrench head, one thread longer than stock for use with seperate washer too, and also fits VORTEC head. Part # 8205 is hardened washer for aluminum heads (34pcs), $9.95 set.

These are American made.
 
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