Hey guys...

I'm about to put the heads on my 393, and I was wondering what kind of bolt lubricant ya like to use.....

 

I usually just use clean motor oil when I install heads (or anything where proper torque is critical). But I am an old-fashioned kind of guy. Hey, it's worked for 80+ years, right?

 

NONE, DONT USE LUBE.!!!!!!
do as the headgasket/manual tells you, lubw will put more clamping force on the part at the same amount of tourque, example. wheel studs, I did this in school this semester, and we did one dry, one with oil, one with anti-seize. but first tourqued them all dry, took them off and put the lube on them, re-tourqued to the same torque, and guess what! the ones with lube had turned farther, therefor making more clamping force. A bad thing. when Ford (or any manufacturer) wants you to use lube they tell you very clearly. I just went trough it with my truck, and this is what fel-pro tells you to do, wire brush the old bolts, or buy new (your supposed to buy new but I cant see doing it when there not torque to yeilds). and run a thread chaser into the holes in the block, making sure you go deep enough to go past the point where the bolt will thread on. thats it. if you use lubrication you are more likely to have a problem down the road, leaky gasket, snapped bolt, streached bolt (ecpecially torque to yeild) and that will lead to failure of the gasket and or warpage of the head. so dont use anything. expecially on something that is so torque critical. Just telling you what Ford is teaching me.

 

Well, in all the instructions, including the instructions that came with the headgasket...as well as my head bolts...say to use lubricant. The point of the lubricant is to make it easier for the bolt to turn for a more accurate torque reading. If it took 10 ft-lbs to turn the bolt, and you applied 100 ft-lbs to that bolt in it's application, the item being torqued would only actually recieve 90 ft-lbs of torque. If it required 100, u'd be that 10ft-lbs shy.

 

If the instructions say lube it, then do so. It DOES make a difference in the "preload", or clamping force. The torque reading is only a means to an end, not an end result itself.

I used to work for an aerospace fastener company and we applied special tread lubes to get the correct preload at the recommended torque.

Jim

 

If you are using ARP fasteners I always use their lube and their torq spec's

 

I am using ARP fasteners...thanks.

 

If you are using arp bolts, then use their moly lube and their torque specs.

In response to ATC_250SX, not using lube on bolts is a bad thing, not a good thing. Most torque specs are used with a lube of some sort. Torqueing a bolt without lube gives inconsistant readings. That's why everything is going to torque to yield bolts. It takes out the the variables of torquing to get a certain amount of stretch in the bolt for the best holding power.

Actually if you don't use lube, you are more likely to have problems down the road.

 

well, I said if the manufacturer reccomends it, I know when I did mine I looked on alldata and ford dosent want you to use lubricant, and from what ive been tought so far, they say only to use lube when its reccomended by the manufacturer. so in this case the head gaskets, and bolt manufacturers wnat you yo use it then use it. they probly even reccomend the specific lubricant. Im not going to continue, im not hear to start wars about things, I was just telling you what I have been taught, and thats all. but he didnt mention above that the makers of the gaskets and bolts said to use lubricant. and there are cirtaint things like for example Lug nuts, that you are not supposed to use lube. if you dont belive me, try the task I outlined before, and you will see the results I saw, for yourself. the further the bolt turns, the more clamping force, regardless of tourque. that may be why ARP wants you to use lubricant. who knows. but I usually follow fords tourque specs, I guess its all about personal preferance.

 

the only question i'm thinking about here is do the head bolts on your motor go into the cooling jacket or are the blind taped?

 

This is a 393, so I am assuming it is a 351W stroker. Then he would have blind holes.

 

ATC_250SX, no need to get defensive

I didn't mention what the instructions said simply because I thought it was common to lube those bolts...I'm still new to engine building.

It's a 351 based 393 stroker

 

I should mention the Felpro gasket instructions should state adding something like an extra 10 lbs of torq added to the head bolts on the intake side (under the valve covers). This is because when you tighten down the intake it unloads the head bolts on that side. ARP dosent state this on their instructions. This exta bit of torq should be added though. You have to figure the percentage differance though between the Flpro extra torq and the lubed ARP torq. Like the 10 lbs becomes 8 lbs more.

 

Does it matter that I am not using felpro gaskets....?

 

No the gasket mfg dosent matter I knew about this issue long before Felpro added it to their instructions. I did learn of it from Felpro through were I work.