Don Terrill’s Speed-Talk

jcisworthy, here is some information you may want to consider. MSC Industrial Supply recently introduced a High Strength / High quality line of Bolts identified as " Bowmalloy " these Fasteners are produced from an Alloy Steel that the molecular make up is undisclosed. These are features that make them superior to common every day bolts ... 180,000 to 200,000 PSI Tensile Strength ( varies with size ). 190,000 average . Precise Rolled threads. The heads of the bolts are 20 percent taller/higher than Grade 8 . Bolt Heads are marked with 12 markings indicating an Alloy Steel makeup . These are made in the USA only . In my MSC Big Book they are on page 1988 . Or you can view them at MSCdirect.com. Mark H.

Maybe try places like aircraft spruce or other aircraft suppliers.. they might have stuff you can match up to what you need..

Check with Jeff at Lee machine/extreme studs in rushville IN. He does a lot of pulling tractor and truck stuff. He’ll make anything up custom, if can get him dimensions. His stuff is on pulling tractor engines making 250 lb of boost

Specialty Fasteners, Chino Ca. stock ARP.

Thank you for the replies and great information everyone

Come on gang!

Where dealing with a Aluminum head here!

Even if the OP could get his hands on 400,000 psi studs it just would not F.ing matter, especially if it boils down to just plain needing to get another head bolt in place.

The extra head bolt is absolutely the best option.

I am in kind of a dilemma where the customer doesn't want to pay more money to add extra bolts and has it in his head, if he ever wants to use different head?? there are holes in the block into water he has to deal with.

Not sure what heads he will use, maybe, sometime in the future, if the stars align but that is what I am dealing with. Kind of like, I'm saving that for someday and your family has to get rid of all your junk you never used after you die, lol. Don't get me wrong, I love junk lol

I would imagine I could talk him into extra bolts if I spend a day doing it for no cost to him but maybe not. I am really at the point where if he is adamantly opposed to extra bolts, its on him if it does not seal. I cannot guarantee these heads will seal without them. I recommended extra head bolts and he had a cow, so I suggested maybe studs would be slightly better.

Will counter-boring the block's threads like some OEMs, and chamfer/countersinking the head, distribute the load a bit better & away from directly around the bolt/stud?
Won't spotfacing the head for a larger hardened washer help?

Really, are there any inadequate OEM head bolts/studs?

Wasn't it BS a few years ago about better finishes on fasteners & blocks & heads along with better lubes, causing fasteners to stretch/snap from over-tightening? Torquing, not torque-angle tightening on regular or TTY fasteners.

With only 8 psi of boost your not even going to double the hp of a NA 400 Hp motor, so in thinking this all over again I am getting the feeling that the tune was off enough to make for detonation in the cylinders your having issues with.

This should be able to be seen on the spark plugs under magnification as little silver purple balls on the plug.
This is basted off and melted piston.

In a worse enough case you would find distressed rod bearings.

I would hope the Indy head was designed to deal with at least 800 Hp, I can’t see how it could not be!

I mentioned earlier, the tune was off and lean. I feel that is the real issue here but out of caution and not wanting to do this again, I was suggesting something better to the customer.

I think the bolts will be fine with a good tune but I guess I am a little gun shy with these heads

The problem with adding the extra bolt (I use a 3/8" stud) to an existing engine is this is fairly close to the bore and it distorts the bore a touch. This is one of those things you should do with a torque plate.

Yeah Ken, I already had that in mind. I made a simple drill jig this morning so I do not have to put an engine in the mill. Only thing left to do with it press the drill bushings in when I get them next week.

I will give the bolts another try with this one and torque them to 110. I think without being lean it will seal and hold.

Engine is done and gone. Head bolts sealed up. I torqued them to the factory iron head spec of 110 lb/ft

Failure was due to pushing pump gas too hard. 110 octane and everything was fine. Best pull listed below

SPS Technology's may have exactly what you need.