[punkin]

Hello all,

I hope this isn't too basic a question but,....here goes.

I'm installing an Aluminum motor into my car...a couple things just occurred to me.

#1 - When adding brackets and accessories (oil filter housing, headers, front pulley brackets), should I use anti-seize compound? My understanding is aluminum is rather prone to galling.

#2 - Expanding on item #1, should I be strictly be using stainless fasteners to avoid the battle of the slow steady migration of the valence electrons?

#3 - Again with the Aluminum block and a 4L80e transmission. This is on the Chevy bolt pattern so no adapter plates are being used. What fastener should I use here? How long, washer (y/n), grade 8 steel or stainless?

Thanks very much for considering these questions.

[Chief of the 60's]

If you ever plan on taking it apart.... YES

I use Grade 8 on just about everything.

Stainless comes in at about a Grade 5.5, some people claim less.

[prostreet64]

I would say yes to using anti seize on those bolts. I don't have aluminum heads or block but I can say that the anti seize does work because after many years, in some cases, I have never had a problem getting header bolts loose and the coating looks about the same as when I put in on. With dissimilar metals it will be a big help.

[i82much]

i say helicoil everything or use studs.

[punkin]

helicoil everything? I didn't see that coming. I suspect you've had some bad experiences?

[Chief of the 60's]

Originally Posted by punkin

helicoil everything? I didn't see that coming. I suspect you've had some bad experiences?

It was GM's repair on that junk Cadillac NorthStar engine.

You see, when you torque a bolt that is screwed into aluminum, all the force pulls on the threads, pulling the threads out. That is what GM did on the NorthStar. People think those engines blew head gaskets when it was the head bolts pulling out of the block causing the head gasket to push out.

By installing a Heli-Coil and using studs, all the torque force is pulling on the threads of the hardened steel stud, not on the aluminum threads. The Heli-Coil is better insurance for longevity.

GM called the Heli-Coil repair procedure, "inserts". Although GM did not go all the way and use studs.

[i82much]

Originally Posted by punkin

helicoil everything? I didn't see that coming. I suspect you've had some bad experiences?

just a stripped header bolt hole on some edelbrock heads. wasn’t stripped too bad so I was able to use a stud and a nut as an alternative. but after that happened, i did some reading and sounds like some engine builders will heli-coil those header bolts as SOP.

i may be wrong but it seems like not such a bad idea for any hole in aluminum? especially for something that gets removed often like accessories, intake, or headers.

[punkin]

Thanks guys. That gives me something to think about. A lot easier now before it's in the car.

Thanks!

[Chief of the 60's]

Or after damage is done.

[lust4speed]

I'd stick with the anti-seize. I have run an All Pontiac aluminum block for 6 years and used ant-sieze when originally putting it together. Only real consideration is to make sure you use the correct length bolts when bolting things on. A bolt with 3/8" thread engagement will survive in a cast iron block but will be a failure point in aluminum. All Pontiac and Kaufman were very generous in supplying very deep threaded holes and appropriate bolts is all you will need. If I have a choice of 1" of thread contact into aluminum or drilling and inserting a heli-coil that's a half inch long or shorter, I'll stay with the full length threads.

[Scarebird]

No reason not to use anti-seize on ALL fasteners, especially in high corrosive environments. Years ago I fabbed seafood processing equipment; when they came back off season from Alaska for modification or repair you could always tell where it was not used

It's cheap, especially compared to your time and knuckle skin.

[Chief of the 60's]

About 150 bucks for an ARP head stud kit is cheap insurance.

Jus' sayin'

[78w72]

something to remember when using anti seize or any lube on threads is to lower the torque rating compared to the dry number. i think its like 5 or 10%.

[Chief of the 60's]

These guys don't recommend any torque changes. I'm going with what they say.

[78w72]

Originally Posted by Chief of the 60's

These guys don't recommend any torque changes. I'm going with what they say.

uh, not entirely true... ARP fastener lubricant specifically states its designed for use with their bolts & studs & the torque ratings they give are not for other bolts or lubes. i just called their tech support & they confirmed this & also confirmed that dry vs wet torque ratings on factory or aftermarket grade 5 or 8 bolts can vary greatly based on the lube used & thread pitch etc. so better go with what they say...

but we are talking about anti seize here not ARP thread lube, my comment was just pointing out a well known fact that wet vs dry torque ratings are different. are you suggesting otherwise?

https://www.google.com/search?source...4dUDCAk&uact=5

[mgarblik]

Just so folks don't get too worried about torque specs., dry vs wet, what lubes and so forth: Factory torque specs. unless otherwise specified are given with clean fasteners in good condition, lightly oiled. This has always been convenient because the fasteners come in huge bins and were not treated for rust or corrosion in our ancient engines. So it was grab and go on the assembly line. The one common exception is the wheel lug nut torque spec. That is to be clean and dry. Of course there are many different sealers, thread lockers and procedures on modern engines, but they don't really apply to our old stuff. On our old engines, the fasteners were way oversized and the fastener torque well below the elastic range or at the very beginning of it. I would use anti-seize as you wish and retain the factory torque specs. True you will get more clamp load, but it should not pull threads or break fasteners due to the large safety factor built in. Concerning ARP lube. As mentioned, their lube is to be used with their fasteners and their specific torque values. It is molly based and slippery. One note of caution with anti-seize: It is petroleum based and not recommended for rubber brake parts as it will cause swelling. It is also very difficult to remove from clothing and can make a hell of a mess.

[78w72]

Originally Posted by mgarblik

It is also very difficult to remove from clothing and can make a hell of a mess.

yep.

good points on the dry vs wet torque ratings, i just wanted to point out that they are different.

& some reputable places list lots of locations that are dry, so if using any lube on threads be aware the torque is different from dry, especially on an aluminum block that may be a concern.

http://www.wallaceracing.com/torque-engine-specs.html