My turbine housing and manifold went over to my friend's shop so he can machine everything. He took off 0.100" from the end of the manifold that mates with the head!
The middle between cyl 2 and 3 was the highest point. I recalled never having this surface machined when I bought the manifold and installed it. I had the T3 flange machined instead. I wonder if its been out from when it was cast at Treadstone? Oh well, its fixed now.
I also had the T3 flange machined to within 0.001". Perfectly flat! (I don't use a T3 gasket as I always blow 'em out).
first pass on the bridgeport. Damn. Looks warped.
that's much better
I then looked at my ARP bolts and realized that the threads were fucked. Hmm. What do I do next? New bolts are about $15.00. The answer? Something more expensive and known to not loosen up. I spent my lunch break one Friday searching all over the internet for my answer. I found it and it resided in California. I remembered hearing about these guys in the mid 1990s when I was restoring my Chevelle. Lots of guys use their fasteners for bolting headers to small and big block chevy heads. I didn't see the bolt I needed for my application but their website said they do custom work and also do US Military contracts. Hmm. Why not give 'em a call?
10minutes later I had four 10mm locking bolts being USPS Priority shipped to my door. Glenn at
Stage8 Fasteners was super helpful and put together a custom turbo flange bolt kit for me.
The standard #3903 turbo flange kit but with 10mm 1.5pitch bolts instead of 1.25pitch bolts. They are probably going to make this a separate kit number as I am not the first to call them asking for a 10mm 1.5 pitch bolt. 4130 chro-moly hardened steel bolts (25mm length) with stainless steel 'teardrop' locking tabs and c-clips.
The design works like this
1) You install the bolts without anything on the threads (loc tite, etc..) and torque them down to 30-40ft-lbs
2) You install the asymmetric teardrop tabs so that the tab is facing the item you are bolting down. The orientation of the teardrop is such so that when the bolt starts to loosen (turns counter clock-wise when looking at the head) the teardrop comes in contact with the item being bolted down and the bolt does not rotate anymore. The teardrops are 12point which interlock on the 6point bolt head. They are ever-so-slightly asymmetric so that if one orientation doesn't work you can flip it over and it should line up.
3) Once satisfied then push the teardrop down until it bottoms out on the bolt head flange and insert the c-clip in the groove within the bolt head.
4) Done. It'll never back out now.
No more messing with NordLock washers. No more messing with loc-tite or anything else. This is a mechanical means of locking the bolt. Unless the threads in the exhaust manifold shear there is no way this will back out prematurely. Especially if properly torqued down.
The downside is a set of four bolts cost me $52 shipped. Now, before you freak out about the price think about how much it will cost you (both time and materials) to redo the T3 bolts on your turbine flange two or three times. More than $52, right? Yup. When put into that perspective this cost is nothing.
Okay. So now that my flanges are machined its time to reassemble.
At this point in the game I realized I forgot one thing... The bolt heads are HUGE. The size of the bolt head flange is about the diameter of a nickel. They require a 14mm socket. My turbine flange did not have a flat face for the bolt to be properly torqued down onto. I didn't have these bolts in my possession when at the machine shop. Knowing that the critically stressed part of the bolt is the fillet from the bolt neck to the bolt head flange I knew to get the proper pre-load and torque I needed the bolt head to sit on a flat surface. Out comes my angle grinder and about an hour's worth of very delicate grinding on the turbine flange to ensure flat surface.
Now we can torque this flange down proper. I used 40-45ft-lbs even though I was told 30-40ft-lbs.
as you can see I took quite a bit of material off in areas.
Also note the orientation of the teardrops.
Not to within 0.001" but good enough for an angle grinder. Note the slot machined into the bolt head for the c-clip.
I like this picture. This is about as much as I can do to match Tyler and Chris.
all done
all re-assembled and properly clocked. time to go back in the car.
(some Agnostic Front playing on the iPhone)
Enjoy!
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Originally Posted by Dan[FN]6262
. Thanks nofearhawk. But to add more to the thread, these won't fit into my current manifold. My machinist is more than likely going to have to cut the bolts down some because I don't want the bolts ending up in the runners (tapping too far). Dan may know how deep I can have my machinist tap, if he chimes in.
"Amy" 
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