Edelbrock Heads and ARP Bolts?

[timty2]

Hello,

I need a little advice. It is time to re-torque the head bolts on our Aluminum Head 440 and I have a question.

I seem to remember reading a post about using ARP bolts someplace, where it was recommended to loosen each ARP bolt slightly and re-sequence the tightening pattern (As I did when the heads were installed.) The Edelbrock head instructions just recommend re-torquing after "X" amount of miles.

Anyone been here before? Should I just re-torque to the final spec, or should I loosen the bolts first and sneek up on the final setting?

Thanks for any help!
Tim

[72Challenger]

Are you using the ARP bolts? If so, follow their instructions.

[timty2]

Hi 72Challenger,

Yeah, That's what I used. I don't remember seeing a re-torquing instruction, but I will review the sheet tonight to be sure.

[Doug Wilson]

Loosen them, re-lube, re-torque.

[cuda66273]

Does ARP not give a torque angle setting for their head bolts?

Torque angle is the absolute best way to assure perfect torque pressure.

I've been studying up on this method and there really is no substitute, simple and effective.

[Doug Wilson]

That's a new one on me - what is it?

[timty2]

Thanks Doug... I had already made up my mind to do just that. I feel even better now!

I DID find the instructions that came with the bolts and they do not provide any instructions on RE-TORQUE procedures. Only the Edelbrock Head instructions talk about this. So, my plan is to follow the sequence, remove the first bolt, lube, take it to the first torque value, and move to the next, etc. Once all the bolts have had their turn comming out, I will again sneek up on the final value in 2 more steps.

72Challenger: The bolt set that I purchased did not even HINT at the "Torque-Angle" setting you mentioned. I would be very interested in what you know about this. Do you have a link to a site that talks about this? I imagine it involves more sophisticated tools than my clicker wrench!

[72Challenger]

Actually, it was Cuda66273 that mentioned something about that torque angle. I've never heard of it. I do know that ARP recommends using bolt stretch to determine the correct torque, but you couldn't do that on a head bolt. For rod bolts it's the best way.

[cuda66273]

For those of you who don't know about tork angle I will attempt to explain it as simply as possible without having a 3 page post....here we go "Engine Building 101" - tork spec's:

Problem: Tork wrenches no matter how accurate you think your's is can give you a variance in reading by as much as 50% due to friction and or poor thread condition.

Result: If your trying to achieve, say a 7000# load and you have a 50% variance in the tension leaving you with 3500 on one bolt and 12000 on the next how can you expect a head gasket to live? ...and we haven't even factored in the variance you'll get because of heat cycling and compression of the gasket.

In rod bolts the effect is even more serious, let's say your machine shop torks the cap on the rod and they end up with 5000#'s on one bolt and 7500 on the other, then they size the big end to perfection, but they sized it or trued the circle when the cap was pulled into an oval. So you take your rods home and dissassemble for a final cleaning and assemble the engine, but this time you use your tork wrench and you get the same pressure but, on the opposite sides, you've just multiplyed the problem and your installing oval rods on a round crank....not a good thing.

The Cure: Bolts are measured by diameter and thread pitch or the movement of the bolt or nut through one revolution....for you Canadian students a good example would be a M10x1" bolt would move 1 MM with each 360 degrees of revolution.

So now come the engineers who have calculated the spring rate, stretch or tork of the fastener by calculating how many degree's of rotation is required to achieve desired clamp load, hence the term "tork angle" and because the tension is achieved by measuring a distance relative to the thread pitch every bolt is identical in tension.

So now we have round rod ends, evenly clamped head gaskets and our motor runs smoother, longer and with less friction and vibration.

Snap-on makes a tork angle gauge that runs right around $50-60 and is available from any of their dealers. Does this mean your brand new tork wrench is obsolete? No, you will still need to set the bolt to bottom which is usually about 30 ft. #'s then you tighten to the "Torque Angle" spec.

If your building a cheapo throw away motor you can get away with using a tork wrench, but if your building a performance piece there is no substitute for the correct tools. With the precision finishing achieved by CNC generated gaskets, bolt threads and modern metalurgy used in the hardning process a tork angle gauge is almost manditory to make these engines live and perform like we expect...why would anyone spend $300.00 on a set of rod bolts and then use a $20.00 tork wrench on them?

I'll add one more note then dismiss class for the day.....Studs Vs. Bolts, now that you understand how and why tork angle works, think about the variance in friction between a head bolt with it's 1.5" of threads binding and galling it's way down in the head and the 1/2" of threads on the nut screwed down on a stud...I think you can see the advantage here...now add a tork angle load setting and you've got the ultimate seal.

I hope I've explained this clearly but if you have any questions...ask away......class dismissed....

[cuda66273]

I guess we should address the original question here....
Re-torque:

I believe and I could be wrong here, but, if you used a tork wrench on the head bolts from the beginning you should use the same wrench. Because of the variances in the pressure applied by the bolts the gasket has probably formed to the twist that you inadvertantly put into the head and block. If you were to use a tork angle gauge you may end up with a poor seal around the bolts that were over tightened and high spots where they were loose.

I would back off the bolts in sequence 1/4 turn and retighten to spec....do not remove the bolt or loosen more than 1/4 turn....you did use moly lube and hardened washers when you installed the heads right?

[timty2]

Hi Cuda66273,

First, thanks for explaining the torque angle concept. Very informative! I'm going to look into this.

The ARP bolts, while they did come with hardend washers, did not provide these tork angle specs. I've always wondered about how precise the torque wrench operation really is. Not all of the force is rotating about the bolt you are tightening, some of it is actually lost by pushing the bolt against the side of the hole/bore. The torque angle setting would seem to remove some of the losses and get you closer to the ideal clamping pressure needed. And, it would seem by using this method, you would not need to re-torque?

The ARP instructions provided two sets of standard torque values, one for use with moly lube, and one for use with 30 wt.

So, given the fact I have used motor oil for 3 separate head installations (2 SB, 1 RB) that have prooven sucessful (at least for me!) I did not use moly lube. Had I had it on hand (and knew BEFORE the project was under way) I probably would have, given this was the first time I used ARP head bolts.

Have you experienced or heard of problems when moly lube isn't used? Any recommendations for me at this point? This is the first set of aluminum heads I have installed, and just want everything to be right!

[cuda66273]

The Professor gives you a "B+".....

It's too late now to try and go back and goop Moly lube under the washers and on the threads but you should be OK if this motor is not over 12:1 compression and the max RPM isn't going to exceed 6400.

Your Felpro performance gaskets should hold just fine...you did use Felpro Performance Gaskets right?

Now that your the proud owner of Aluminum heads you have already marked down in your day timer to change the anti freeze every 12 months so I won't need to remind you next year about this time....did I tell you that I turned 50 yesterday and my memory seems to be failing me at times?....better make sure you have it penciled in....

[Doug Wilson]

my head hrts... again.

He's kidding about his age - he's only 35.

But he looks 25.

[Doug Wilson]

Would someone please tell me what a "tork" wrench is... is it some new kinda pliars. I always use a really good pair of pliars when I put engines and stuff together. Should I get this new kind?

[72Challenger]

Oh, man...

[cuda66273]

Thanks Doug

We gonna see you at the Mopar Nats on Sunday?????

We're heading down on Friday after work...uhhhh well after Holley's off work...us retired types don't worry about that work stuff.....LOL

[Doug Wilson]

I'd love to go, but I don't think I can. Deanna is showing her horses all this week, and they need someone to be there to blame if she doesn't win an event. Kinda like you at the drags!!

[cuda66273]

I can't believe these people don't they check the racer scheduale before they plan these things???

No, I don't need to have anyone there to blame, 98 times out of 100 the finger can be pointed straight back 180 degrees.

Except for that blatent screwing I got last week on that perfect light, the other time the car let me down.....

You'll be missed..............

[RogerH]

Well, to be precise, to torque a bolt is only an approximation into applying load to it. The correct way, for every bolt that gets installed, is to figure out how much you want to stretch it, which in turn is the load on the threads. Which is why engine builders, when tightening down the rod bolts, actually measure the bolt stretch, instead of applied torque. But not every bolt can be assembled in such a way, which is why we have to use torque instead.

Roger

[timty2]

Doug and Cuda: You guys are a crackup! I love this site!

Getting me to laugh is no easy thing lately. Just had another layoff (Round 5 this year) in my division. Down to about 20 people now. High Tech capital equipment is just not selling.

At any rate, Thanks for the B+! I'll take that. The Charger is a bone stock R/T car, right down to the cam... Never opened before except for the intake manifold many years ago. The heads really woke things up!

I did get the recommended fel-pro HG's, so maybe bump me up to an A-?

The shop we had the radiator install the new core recommended we add a ground cable from the head to the radiator or a near-by chassis mount. He said this would help reduce the electrolysis that results from the dissimilar metals involved (Steel/Cast Iron and Aluminum).

Anyone have thoughts on this ? Will this help to extend the coolant change interval to somethng a little less frequent? I added the ground cable anyway... figured that adding the cable can't hurt anything... The charging system has never worked better, by the way... BONUS!

[timty2]

Thanks RogerH...

As in most things in life, there are always comprimises. Nice explanation.

I was just tinkin' over hea... Maybe the electrolysis topic should be a new post?

[cuda66273]

I had one going a couple of weeks agao on electrolysis...dissolved one of my freeze plugs in less than a year...

My Brother, who owns a Forklift Company in Canada tells me to use water soluble oil to help prevent this...about 2 oz.

You can have a A- only if you promise me you'll change that antifreeze every year...ground strap or not.


Did Doug ever tell you Guy's that he shaved his head so he could look like me??


BTW..hey Doug, you looked alot better bald, kinda like me....

[cuda66273]

Hey Roger,
Haven't heard much from you lately? Hope you've been busy getting my Super Victor sample manifold ready...LOL...sure would look good on the new 915 J heads I'm working on...

I should have clearified my post I was really referring to head bolt tork and main bearings caps, I guess my example of rod ovaling was a poor choice. You are absolutely correct a stretch gauge is the best way to tighten rod bearing caps.

Anyhow I'm sure everyone got the main gist of it.

Mopar Nats this weekend here in the Pacific NW....we'll be out to defend our PRO title from 2001, should be easy with the new "Edelbrock" decals on the window....

[Nightri1]

OK you guys got it all except for one thing I did not see mentioned. Anti-freeze AND distilled water. This is the recommended mix to help reduce corrosion of the heads and radiator. You can use tap water but the distilled IS better.

[1972roadrunner]

i haven't heard of using distilled water in the radiator, but i have heard of using it in a battery when the acid level gets low for any reason.... makes sense though...chlorine and whatever is in tap water is bad for engines!

[RogerH]

cuda......

Yeah, I have been busy lately. I was working a lot on the Super Victor, but have been doing a lot on a new Honda manifold lately. We ran into a stumbling block with the Super Victor, the engine we received from Herb McCandless didn't make the power we were looking for, after looking into the engine, it appears we have the wrong heads on the engine. They were supposed to be the fully port and polished ones that flowed 300+ cfm, and I guess Indy had sent Herb just a mild polished one that barely flowed 270cfm intake, 180 exhaust. So we are going to fix the head problem and run the prototype again. So maybe by the end of next week, or the following week, we will have some good numbers!

Yeah....I bet those Edelbrock stickers make you run about .2 sec quicker!

Roger

[cuda66273]

Great I'll dial a 12.07 in the first round...thanks

BTW what kind of head flow will my Air Gap manifold handle?

[RogerH]

cuda....

Well, I wish I could answer that one. The truth is, we do not flow test intake manifolds. Sometimes during development, we will flow test some, but they are mainly late model EFI type manifolds. The issues with flow testing is that more than just flow numbers will determine how well a manifold will work on an engine.

I would think that for a Air-Gap manifold, which is an RPM manifold, I would use this manifold to go with a street used high performance engine. When you get into drag racing with big cams and turning higher sustained revs, a single plane manifold would be better.

There really isn't any easy answer, you really need to look at the application of the manifold, rather than just flow numbers.

Roger

[AndyF]

Hey Roger, would you find the ding-a-ling there at Edelbrock who specified angled valve cover bolts on the big block aluminum head and give him a good whipping for me?

Please drill and tap those holes 90 degrees to the valve cover rails so a person can use long bolts or studs with cast valve covers!

[cuda66273]

Roger,

The Dual plane design seems to work good on my small cube engine ....without a little help on the bottom end I'd need to launch at 6000 and I shift at 6200....that's a tough one....

HEY!, the decals worked!

Friday grudge racing: We went 5 straight

Saturday Points race:Got to the semi's ...and the pay window! Car ran 4 passes at 12.300! Broke out in round 5 12.298...took the stripe by .008.

Sunday Mopar Nats: I lifted at the stripe racing the Vitamin D Dodge and let him around me by .0022....if I hadn't have lifted she would have run 12.346 on a 12.34 dial....instead of the 12.366....gave it to him.
The track was bad all morning I spun in all 3 TnT's and couldn't get a dial time...just guessed, I should have trusted the car...oh well.

We got to the semi's again in the consey round and where we raced a 16 sec. car, got on the convertor too soon, backed off and hit it again and lost concentration .....the big red one.

Saturdays great run put us on the bubble for Team Woodburn and the Division 6 Regional Finals, keep your fingers crossed for us...2 more races to go.

That last round Sunday was an endurance test...94 degrees, 34% humidity and 9 minutes between rounds, I guess I'm getting too old to recover in 9 minutes after 3 minutes in a microwave....temp inside car was 118 degrees!