Studs for WD45

ACnightmare · May 1, 2012

I"m looking for studs for a WD45. My headbolts are not holding anymore. Anyone know where I can find some and what size would be needed?

Sweeper · May 2, 2012

Get them from ARP.

wi50 · May 2, 2012

I have a complete set of ARP studs and nuts for the Allis 4" tall heads on hand. I'll look at the bags when I get to the shop tomorrow afternoon and post the quantity and part number of each item so you can order them.

ACnightmare · May 3, 2012

Thank you for the advice. I look forward to your information wi50

Aaron SEIA · May 3, 2012

Don't mean to hijack a thread but I've got a question. How do the studs work better than the original bolts? If they are the same diameter and torqued the same what am I missing? Tougher material that doesn't stretch under high horsepower?
AaronSEIA

wi50 · May 3, 2012

Aaron,
In simple terms a stud will hold more than a bolt as the torque applied is pulling rather than twisted. Also these ARP studs are made of better material. Fastners are nothing more than a spring in a sense.

Now for the part numbers and quantities.

12 nuts, 1/2-20 thread, part # 300-8304
2 nuts 7/16-20 thread, part # 300-8303
3 studs, 7/16X5.25 length, ARP AP5250-1LB
3 studs, 1/2X4.625 length, ARP AR46201LB-ARP
5 studs, 1/2X5.250 length, ARP AR5-250-1LB
4 studs, 1/2X5.750 length, ARP AR5-750-1LB

The studs use a 1/2X13 thread on the base, and a 1/2X20 thread on top, the 7/16 studs use a 7/16X14 thread on the base and a 7/16X20 thread on top. Nuts are 12 point. It's a quick way to blow the better part of $200 to keep the head on.

Those are the part numbers from Summit Raceing, I typically order them from Summit and they ship direct from ARP so it takes a little while. Last time it took about 2 weeks. I've got the part numbers of different rod bolts that I use also from ARP when putting good bolts in some of these old tractor rods also if you want.

VicS · May 3, 2012

It's because of the fine threaded nut on top. 20
threads per inch will clamp tighter at 100 ft lbs.
than 13 threads per inch.

Anonymous-0 · May 4, 2012

(quoted from post at 19:06:41 05/03/12) It's because of the fine threaded nut on top. 20
threads per inch will clamp tighter at 100 ft lbs.
than 13 threads per inch.

yeap , grade 8 1/2 inch allthread will hold 90ft lbs for those on the cheap just replace them everytime you stretch them .ps if the engine is dieing and rolling backwards head gasket pushes out no matter what .

ACnightmare · May 7, 2012

Thank you so much that saved me a ton of time and
headache

Studs for WD45

ACnightmare

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Sweeper

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wi50

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ACnightmare

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Aaron SEIA

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wi50

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VicS

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Anonymous-0

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ACnightmare

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