I was using Doorman 3" long studs to hold the max wedge style rocker stands and the drivers side front stud broke after about 200 street miles? Do I have bad luck, or is there a problem running about 770+ open spring pressures on these Victor heads?

Shaft broke because the stud broke. I'm not sure what grade a Dorman stud is but I don't use them for anything significant. You can buy individual studs directly from ARP. Tell them what size you want. My paired T&D's had 2 studs on each mounting bridge that I thought should be longer. Bought new ones from ARP, reasonable.
Doug

When I had my Stage 6's I had rocker issues until I added these

and changed the studs to 7/16"


http://www.timesert.com/html/bigsert.html



Chris. .

Scrap the Dorman. Cheap material for such a build.
Step up on quality bolts and there strength.

I agree the stud went first... not sure if it
was loose or just weak

Probably a reason Dorman is at the hardware store, and ARP is at the Speedshop.



...and I stand corrected

http://www.summitracing.com/parts/rnb-675-099

...but I'd probably been looking more this direction

http://www.summitracing.com/parts/arp-aj3-15l

to my knowledge all those hardware/auto store studs are grade 5.

99% of the bolts in my car are grade 8 or above
except for some sheet metal screws

[quote=Chris'sBarracuda]
When I had my Stage 6's I had rocker issues until I added these

and changed the studs to 7/16"

Another stage 6... pulled the threads, bent broke the shaft. the heads weren't drilled deep enough for a longer bolt/ more thread engagement. Fixed it the same way as Chris.

Jim, you have ARP fasteners on everything else in/on that engine. Why did you go Doorman for the rocker shafts?

another prob Trendz is using those factory hold downs. They'll elongate the shafts over time and the rockers won't slide off the shafts.... found that out the hard way before going to aluminum hold downs with more surface area...

With race cars after they hit a certain point you can spend a lot of money hopefully once the first time or do it on the cheap MANY times. The choice is yours.

I used studs with 120k psi rating.

When I ordered the studs from Summit, they did not have a 3" long ARP, and the Dorman studs I used are advertised as Grade 8? I even checked their catalog.

These were torqued to 35ft/lbs, do you think I need more pre-load?
ARP shows 45 ft/lbs for 3/8", 180,000 psi bolts?

I did order some ARP studs to replace these.

The heads have already been modified with 3/4" long timesert thread inserts, after milling the stock shafts off and using the Max wedge type rocker stands/hold downs. I'm not sure how I could goto 7/16" with the reduced diameter T&D shafts and have the rockers oil through the rocker shaft?

How much would it cost to have ARP make some custom studs???

FWIW, I ordered these: ARP-AJ3000-5B
Summit has the material listed wrong as 4037?

This is the description from ARP:
Stud, 8740 Chromoly, Black Oxide, 3/8-16 in. Base Thread, 3/8-24 in. Top Thread, 3.0 in. Length, Each

These ARP individual studs are made from 8740 chromoly steel with 190,000 psi tensile strength. They are precision centerless-ground and thread-rolled to Mil-S-8879 specs and have a black oxide finish. A nut and washer are sold separately.

yes, but note that nasty "pinch" on the Dorman stud where the threaded part meets the non threaded part.... I'm betting you won't see that on an ARP, and hopefully the ARP isn't threaded most of the length like the Dorman.

Hmmm, got me thinkin' as I run a couple of Dorman studs on my Victor/Sharp setup. I don't remember why but, like you, I'm sure it was because I couldn't find the right length ARP at the time. Dorman did list as grade 8. Are those stands positively located or just located by the studs? I remember your center rocker stand issues from a few years ago which prompted me to install inserts deeper in head before bolting them on. Thanks for posting back then. I hope your valve train issues go away soon...

What I didn't like about the ARP 3" studs was that they are not threaded long enough on either end.

http://www.mcmaster.com/#standard-threaded-rods/=yfs8yu

If those don't work I'll use some grade 9 stuff:

http://www.mcmaster.com/#standard-cap-screws/=yfscrf

Sorry to see you are having problems again!

I ended up using the indy rocker studs that allowed me to have full thread engagement in the victor heads using the T&D rockers.

I got an E-mail from ARP and they said this part number:

PN: AJ3.050-1LB is an 8740 stud with .825" of 3/8-16 and .850" of 3/8-24. Torque would be 50 ft/lbs using the ARP Ultra Torque Lube.

Best regards,

Alan Nichols
Sales & Technical

Automotive Racing Products
1863 Eastman Ave.
Ventura, CA 93003
Toll Free: 800-826-3045


So, I ordered some of these too.

I think part of the problem was not enough pre-load on the studs with only 35 ft/lbs?

Can you be certain valvetrain instability didn't break the stud and the shaft?