Myself and another member(Bill) have been working with ARP for a head stud that utilizes a better material than the standard 190,000psi head stud.

This stronger stud is for those who run very high compression ratios, boost, or No2.

Lead time for the studs is 6 weeks.

In order to obtain this pricing, 5 sets need to be purchased. We have 4 spoken for at the moment. If we reach 10 sets then the price drops slightly.

The head studs will consist of the ARP 2000 material and contain studs, nuts, and washers.

The cut off for this buy will be Thursday, March 4, 2010 (Unless of course we don't have the additional set to meet the ARP level)

Cost for the set will be $180 plus shipping.

Bill and I will handle the finances with ARP with all of the studs being shipped to a central location for distribution. We will be posting this over on FABO as well. If you are interested, please confirm via PM to me and I will confirm your request.



This is what a lifting head gasket looks like even with the block o-ringed.




We tried for the 260,000psi material but these were still in the neighborhood of $400 per set if 10 sets were sold.

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11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

I'll be in for a set Espically in 6 weeks.

low on cash now.



Greg

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http://www.youtube.com/hyperpack

Is the problem really the stud strength? Will the 15.8% increase in tensile strength cure the problem?

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Joshua

I still expect these to be marginal at best with the boost level I want to run. 7/16" is small and there are only 4 bolts per cylinder. I think the 4 bolts per cyl is the real limiting factor. It's the best we can do unless we want to go $400/set.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

7 from now. That's if ARP keeps their word.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

There was a fellow that built a blown 225 once and he upgraded to 1/2" studs.

_________________
Joshua

We researched it and decided against it. See Below.

Exner Geek
TBI Slant 6


Joined: 20 Jul 2008
Posts: 163
Location: St. Louis Park, MN
Post subject: (Sat May 30, 2009 7:16 pm)


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Several racers have fitted 1/2" studs and it definately can be done. When you rethread a 7/16 hole for 1/2" you will find that the hole is already larger than called for with a 1/2" tap, that means the threads will not be shaped quite right and it will not be as strong as it could be. A machinist that I respect recommended not to do it for that reason. I do know that Mark Goodman and others did it anyway and were able to torque the nuts to 95# or more which should help to hold the head down. The tapping must be done with some precision, probably on a milling machine or the studs will not be perfectly straight. I am sure that ARP has a half inch stud that could be used, you just have to find another applcation with a similar length. Before a 7/16" kit for Slant 6s was available we used to buy the kit for the 455" Oldsmobile, maybe that or a similar motor had a 1/2" stud available. You may also have to enlarge the bolt holes in the heads slightly.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Update.

We have commitments for six, possibly seven sets.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Yeah, having only 4 bolts per cylinder does present challenges from time to time. On the Chevy 6's that i've built for several Comp Eliminator guys, through the evolution of their engine programs going from 7/16 to 1/2 head studs is a real must, especially with the ultra high compression these engines have. But in cases where you don't have the ability to perform or do this, when using an O-ringed block also machining a reciever groove in the deck of the head will help prevent the cylinder pressure from seeping between the gasket. I've also done quite a few NMCA turbo 5.0 Mustangs that have exceeded 20 lbs. of boost, and only have 4 bolts per cylinder and use 7/16 head studs. So, this is some crossover technology that will also help in your situation. Also, many of the newer LS series Chevy V8's are also produced with 4 bolts/cyl., and they are machining the head bolt holes in the block out to a much larger metric o/s thread, this way they are removing all the existing threads of the smaller bolt size, and the new holes start out with the correct tap drill size before rethreading. This could also be a possibility for you as well. I dont think that staying at 7/16 will be of much benefit for you unless you also do the reciever groove mod. Its not the strength of the bolts or studs that is the problem, its their lack of being able to sqeeze the gasket tight enough. A 1/2 bolt or stud will apply quite a bit more clamping force to the gaskets than a 7/16 can be made to. Just some thoughts to consider. Keep us posted on your results.

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There's no such thing as too much cam....only not enough engine!

Unfortunately, my block was done before I realized the issue. I would have tried larger studs if I had known at the time. Oh well, next one. Might try and see if there is a metric one that would work.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

Maybe you could look into the reciever groove option. I think that this could still be helpful for you.

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There's no such thing as too much cam....only not enough engine!

Tomorrow (thursday)is the last day if anyone wants in on this.

_________________
11.02 @ 120.56
http://www.youtube.com/watch?v=EAxRmoDgsdY
Chassis dyno
http://www.youtube.com/watch?v=wd6hFGzLJMc

What about a 9/16 fine threaded stud?

Hole size for the threads is 33/64, just over the 1/2 size...

Or a
M14x1mm 13mm drill
M14x1.25mm 12.8mm drill

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes

9/16 fine was what I was/am going to use.
I checked a junk block and it looks like there is enough on the head and block both.
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

Remember that the stud is screwing into cast iron. A coarse thread is required due to the brittle nature of cast iron.

It may be possible to use a HeliCoil or equivalent in the block to obtain 75% thread engagement.

Ken