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Discussion Starter #1
OK, I am installing my edelbrock heads on my 351W and I have three different torque specs. Which one am I supposed to use?

1) Ford Shop Manual = 95 - 100 Lbs (cast heads)
2) Edelbrock Instructions = 100 - 110 Lbs (Alum heads)
3) ARP Head Bolt Install Inst = 75 (Alum heads)

Which one is right??

ARRRRRGGGGG!
 

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Discussion Starter #3
Thanks, 69RedMach1! Taking them up to 105 (splitting the difference between 100 - 110.
 

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I dunno about the W's, but for the 460 RPM's they make a SPECIFIC headbolt to deal with the tremendous amount of torque they require.
 

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......Re-torque them also..........
This would depend upon the head gasket being used. I'm using ROL head gaskets and they do not need to be re-torqued. That's assuming they are installed correctly (torque and sequence) in the first place.

Once the gasket coating/material is heated, it is sealed. If you re-torque you run the chance of disturbing the initial seal.

I would always follow the instructions that came with the head gasket. Any doubt and check with the gasket maker.

BTW, I've used ROL head gaskets on 3 different engines. Always held up great and no problems. :)
 

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If you read Edelbrock's instructions it says "re-torquing not necessary except in racing conditions." I've run them both ways, they blew when not retorqued and using ARP's specs, they have not had any problems using my method. Granted I run my car pretty hard, but I think Aluminum expands and contracts too much. Besides, every guy I talk to at the track re-torques.
Pete
 

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I use Edelbrock's torque, ARP bolts and methodology. The 100 lbs is for the short bolts, 110 for the longer. If you used 105 on both, don't worry, you'll be fine.
 

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Some basics....
Fastener torque (assuming torque is being applied without angular distortion) is a function of diameter, thread pitch, fastener tensile strength, thread type, thread finish and material the fastener is being threaded into, along with the co-efficient of friction or any lubricants employed.

Given that ARP can quantify all those parameters (no one else can in the case of your application), ARP specs are the ones to be followed.

As far as retorquing is concerned, I've run a variety of o-ringed and non o-ringed blocks/heads over the years and haven't re-torqued my fasteners. It should be noted that I never run bolts, always studs. The most recent heads I've used (Edelbrock RPM's) were installed following ARP specs, not re-torqued. The engine ran for 2.5 seasons before I parked the car. No problems. Gaskets have been Fel-Pro's for as long as I can recall. Compression ratios have never been less than 12:1.

Hope that helps!
 

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Like Pat said, with the ARP studs, they have a fine pitch thread at the top and use a lubricated washer, therefore probably the load developed in the stud at 75 ft-lbs is equivalent to 105 with a bolt and coarse threads, no lubricated washer. I used 75 with no problems although not a super high-powered application. Going to 105 could potentially overload the threads in the block or stretch the shaft.
 
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