Forkspear

Anyone know anything about these hardened head bolts? At $130 they are much cheaper than studs.

http://www.mightydiesel.com/store/pr...oducts_id=1011

Forkspear

No one has tried using hardened bolts instead of studs????????

92smokin blacky

I've heard of them before and have heard pretty good things about them. I'm sure they'd probably be better than using stock bolts, and definately cheaper than studs, might be worth trying out. But I think if you were pushin over 50-60 lbs of boost I think it would be worth it to spend the extra coin for studs.

stillsmokin209

I wouldn't use those if you paid me.
Allen heads for studs? What a joke.
Torque to stock specs it says. So where does the extra clamping force come from? Their super duper "hardened material"? Please. I would take stock bolts torqued to 125+ any day. Studs are around $400, do that or stick with stock bolts.

ARbowhunter7

Allen heads are not completely uncommon on custom non-metric head studs. I recently saw a set of 9/16" studs from Keating Machine that had a huge allen head.

The appeal of these hardened bolts is not extra clamping force, it's their resistance to the "head bolt stretch" that is associated with stocker head bolts. The hardened bolts can be torqued to 125, also.

Also, ARP's for a 12v are $500, plus install. Could get close to $1,000 out the door, depending on the shop.

That said, I'd go for the studs over hardened bolts any day of the week. O-ring it at the same time. If you're going to do it, do it right.

Forkspear

Sounds like retorquing the stock bolts is the way to go then. Allen head bolts are no problem. I changed a head gasket on a 91 turbo eclipse that had allen head bolts from the factory. Its just a different design.

in the red

i have them on my puller and nurmous other trucks i have worked on i get mine local and sell the for 100 bucks my puller has seen 50+ pounds of boost on numorous hook for over four years. i torqued them to stock which is 90 pounds 90 degrees and have checked them with torgue wrench and have seen up to 135lbs till started to turn again. they will not stretch like a stock bolt just my two cents

stillsmokin209

I stand corrected. If they came from keating I would have not one problem using them. That being said the bolts in question are not from keating.

Clamping force is what holds the head down, resistance to stretch is what keeps it there. Stock bolts can also be torqued to 125 ft/lbs.

$500 for standard 2000 series studs?
http://www.kjbmotorsports.com/engine...rphead12v.html
Try $400.
And since when do studs cost $500 to install? Machining the rockers is not nearly that much, and install can be done in your driveway.

There is more than one way to do it right. As I recall keating and garmon are both partial toward headbolts. Seem to work fine on morrisons pro stock truck.
Studs are a piece of mind and do offer a greater tensile strength and clamping force over a factory bolt, but when done right bolts can hold their own.

Factory bolts or reputable studs. I don't trust the bolts in question.

ARbowhunter7

The bolts in question...I probably wouldn't trust them either with stratospheric boost. I wasn't making the case for them at all, I was just clearing up their selling point and appeal. If you would reread my original post, I recommended the studs with an o-ring job.

But you are correct, Darrens truck seems to hold the boost fine, as well as Jeff Prince's truck that Keating did the headwork on. These trucks make more boost than most of ours put together. I just would rather go the head stud route, myself.

BTW, good find on the studs. I haven't seen them that cheap.

stillsmokin209

Studs and orings are hard to beat, I'm with ya on that. My p pumped 24v runs fire rings and arp 625's. Not a single problem there. Before that arp 2000's held 60psi for over a year on the stock gasket. With the 1990 I now have I'm going the bolt route, since I don't plan on much power, and it's a budget thing as well.

As for the bolts in question, their just not my style. To each his own though.
To the OP, studs or factory bolts, your choice man. Both work well.

Forkspear

Anyone have links to other bolts? These were all I could find.