You won't believe how much these cost. Take a guess...

[jayb]

Since the beginning of March I've finally been getting good cylinder head castings for the FE Power cylinder head project, and I just got the first set back from my local shop with the valve job done, so I've been working on getting my dyno mule ready to run.  I've been refining the design of my rocker arm system that is required for use with these heads, and thanks to some help from Bill Conley I've got that pretty much dialed in now.  The rocker system does require some special hardware though, in particular the nuts for the head studs on the intake side.  These nuts have a 1/2-20 thread on one side to screw onto the head studs, and a 3/8-16 thread on the other side.  The bar that goes across the head and supports the rocker shafts bolts into these nuts with some 3/8-16 bolts. 

I did this because I didn't want to rely only on bolts into the cylinder head itself to attach this bar, after seeing what happens to some other heads (specifically Blue Thunder High Risers), when a lot of valve spring pressure is used.  Some of you may have seen pictures of the top of the port being ripped right off the head in that case.  Attaching to the head studs is much better, so my system uses that approach.  As a result I need a nut like the one shown in the pictures below:





It's pretty simple.  It is just 13/16" round stock, 1.4" long with a 5/8" hex cut into the top of it, so you can tighten the nut.  The underside is threaded for 1/2-20, and the top is threaded for 3/8-16.  Nothing to it.

I went to ARP and asked how much it was going to cost for 20 prototypes, and a production run of 300.  Take a guess, folks, I'll post the answer tomorrow.  Bottom line is I may be making these myself...

[machoneman]

$4,000 for the first 20 prototypes, then $90 each for the 300 run.

[WConley]

Bob's guess sounds spot-on to what I was thinking for the first 20, though I'd say the 300 "production" pieces would be about $125 each.

You may want to give these guys a call - Coupling Nut Supply.  They claim to make lots of styles of "Reducer Coupling Nuts" and they welcome custom jobs.

http://cnssales.com/?page_id=20

It's always the little things you weren't expecting... 

[57 lima bean]

          Fordytwo dollars a piece.Because 42 is the answer.

[temarey]

Mc Master Carr has 1/2 - 20 grade 8 nuts 1.75 long and thread inserts 1/2 - 20 x 3/8 -16 . Nuts are $22.93 and inserts are 3.93
This might be too long of a package to work for you ,but is a rough idea of realistic cost

[KMcCullah]

Would a change in material/method help with the cost? A chunk of hex material with a turned back end maybe? Versus what appears to be round material with a milled hex? Well that sounded just like bb.

I'm guessing 8k+ total for the first run. Formed threads vs cut threads, ARP is pretty much the shit. 

[jayb]

The material is chrome moly steel, about a buck and quarter for a 1.625" length, which is what you'd need to make the nuts.  Hex stock is more expensive to start with, and it would still have to be cut down because a 13/16" hex would require a socket of the same size, and that won't fit in the counterbores for the head studs.

A lot of you guys are close on the numbers, I must just be cheap because the pricing I got pretty much blew me away.  I will probably end up making these myself, it's just not that hard to do...

[gdaddy01]

nine hundred dollars and some change .

[FElony]

I'm thinking about 3000 cheezburgrz, give or take depending on which cheez. Am I right?

[Dan859]

I'm thinking about 3000 cheezburgrz, give or take depending on which cheez. Am I right?

Where do you come up with this stuff???  LOL!  I'll gladly pay you Thursday for a cheezeburger today!

[FElony]

I'm thinking about 3000 cheezburgrz, give or take depending on which cheez. Am I right?

Where do you come up with this stuff???  LOL!  I'll gladly pay you Thursday for a cheezeburger today!

Simple. The value of a cheezburgr can swing between a buck and ten bucks, depending on which retailer is chosen. Therefore, if Jay says 12 grand cost, I find a retailer that sells cheezburgrs for 4 bucks, and I automatically win his red '69 Cobra. If he says higher or lower, I adjust the value accordingly, down to the penny. I can't lose.

No freebies, Wimpy.   

[Dan859]

No wonder I flunked math.  I forgot to take the Cheezeburger Constant into account.  Life must be endlessly fascinating in FElony world  .   You probably played Calvinball when you were a kid)). 

[TomP]

I will say the 300 production run will be ten cents each... $30 and the 20 prototypes will be ten dollars each... $200

Or are 1964 and Chinese prices not accurate?

[jayb]

$216.80 each for the samples, $25.12 each for a quantity of 300.

I think that is simply ridiculous.  I have to supply 10 of each of these with each pair of cylinder heads.  That will increase the cost of the heads by $250!  Unacceptable.  I will be finding a different alternative, even if it means making them myself.

[TomP]

Yeah that is quite a bunch. A 3/8" nut welded to the top of a 1/2" fine thread nut would even work if it sits on the threads above the nut holding the head down. Or is this to replace the head bolt/stud/nut?