Holts or Suds

[Prawbly]

After buying some aluminum heads , the cost of a set of studs stopped me cold. I cant afford to pay the price for some U.S. made studs. I figured I would just use bolts. Well a fellow told me not to use a tap to clean the threads because I would damage the original threads. My question is will the standard grade 8 bolts damage the original threads ?

[Scotty's 52 F3]

They make taps specifically for cleaning threads instead of cutting threads. Maybe what he was referring to.

[Prawbly]

That makes sense. I'm still curious about using bolts that have straight cut threads.

[35fordtn]

Why not order a set of Roy Nacewicz studs?? WELL worth the $$

[Prawbly]

Thanks. I went to the site. Looks like a great place. I'm goings to contact them in regards to the studs and aluminum heads. Thanks again - Pat

[Brian]

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One problem [maybe] with using grade 8 bolts is the head size; 5/8" as opposed to 11/16" as original. To overcome that, I have, in the past used Cat bolts, they have 11/16" heads but certainly not a cheap exercise!

[Flowmeister]

I've never regretted a single dollar i've spent with Roy Nacewicz
Great guy, great business, great products.

[JM 35 Sedan]

I second, or would that be third, the suggestion to buy those studs from Roy Nacewicz. I personally would not use bolts, jmho. Call and talk to him about those studs, or any other hardware you may need for your old Ford. Be prepared for a great conversation with one of our premier suppliers in the hobby.

[rockfla]

To answer your question NO Grd 8 bolts would not damage your threads. All commercial bolts, A307/Grd 2, Grd 5 and Grd 8 are a class 2A thread and the tolerances are not that close as to do damage to the treads. The problem with Grd 8 Bolts is, that as previously mentioned, they have what is called a "Finished" head and even with the stud and nut set up to remain stock looking Ford used "Heavy" pattern nuts on the early Flatheads and I suppose Heavy Head Bolts for the 8BA's so your gonna be one wrench size off with Grd 8 Bolts. Commercially the only real bolt available made in a Heavy Head pattern that will handle the heat cycles that head bolts go through would be a material called B7.....BUT finding a B7 bolt the length you will need for the heads could be somewhat tedious depending on your local fastener supplier B7 is a heat treated Grd 5 material so your looking at an approximate tensile of 120,000 psi where Grd 8 and I'm sure ARP studs (and Others) are 150,000 psi (or Higher).

[rockfla]

And B7 bolts would be "stamped" so for Identification purposes in the commercial/industrial market so one would have to turn the "Head Markings" off the bolt to retain a "stock" appearance.

[Ol' Ron]

Most hardware stores sell a 7/16 NC bolt, this along with a hardened washer,is more than adaquite for clamping any flathead cylinder head. Torque to 45 ft/lbs for at least 3 heat cycles. They may not look right, but will work mechanically. However If using high quantities of nitro you may want to find a better bolt.

[rockfla]

To Ole Ron's point
I would say that's true for Grd 5 and up. A307/Grd 2 bolts would be torqued well beyond the published torque values and would most likely stretch a good bit through the many heat cycles of a Flathead. The bigger problem is "MOST" hardware stores sell zinc plated or yellow zinc plated bolts and they are not the best to use in higher temperature application (250 and up) due to the possibility of Hydrogen Embrittlement. So if one were to use say a Grd 5 or Grd 8 bolt I would suggest it be one of plain finish!!!!