rossman

Just pull it out and check it. It may be worn or broken internally.

Had the exact same thing happen on my car with stock suspension ,Z31t axles, and Modern Motorsports adapters. Stretching out the boot might help but it relies on friction to hold it in place so it may just slide back after some period of time. But, it's worth a shot. I had decided that the differential was flexing too much so I installed TTT mustache bar (previously stock 280z) and ground the corner off the LCA where it comes close to the boot. The car is still on jack stands so I don't know if that combination worked. Installing aftermarket LCAs hadn't crossed my mind until now....

At least you figured it out! All of us that were trying to help assumed that the control setup was good. Take it as a lesson learned; start with the simple stuff first and verify before you move on to the next, more complex possible cause.

I had a pair of the AZC rear brackets that were set up for parking calipers but destroyed them, cutting them off my car. IIRC the brackets were set up for some never developed custom AZC parking caliper not Wilwoods. @Woza01 produced a set of steel rear brackets that did incorporate both the Wilwood brake calipers and parking brake caliper.

Good eye Villeman! That dogleg has been patched for sure. Zoom all the way into the bottom on the dogleg and you can see the crappy body work underneath the paint. Also, it looks like rust bubbles underneath the paint on the left side hatch area. +1 *close up* pictures of the battery tray and underbody, especially the frame rails. I would be very skeptical of anybody who claims a rust free car unless they have the bare metal pictures to prove it. Otherwise, it's all just talk.

Comparing boost numbers between an old L6 and a 2JZ is a bit like comparing apples and oranges. I'm sure your engine is flowing considerably more air than mine at 10 psi, requiring your wastegate to handle a higher volume of air to keep it there.

I'm running a 5lbs spring in the MV-S. I typically run 10 psi but have run 8 psi and 15 psi at times. It seems to be stable but I haven't logged it. No HP numbers yet.

FWIW, my TiAL MV-S 38mm wastegate setup is similar to Softopz's "A" setup above but with it merges into the downpipe a little further down past the second bend. I'm also running a GT35R and have no problems controlling boost.

Chickenman covered it but you might want to also consider your wastegate outlet pipe too. If the outlet is routed to a high pressure or very turbulent location in the exhaust pipe it will affect the efficiency of the wastegate. You could test this pretty easily by dumping to atmosphere like a screamer pipe. If the boost becomes controllable then you found your issue or at least part of your issue.

My engine builder, Rebello recommended 1/2 bottle of Lucas TB Zinc Plus combined with a 50/50 mix of Motorcraft 5W-30 synthetic blend and Penzoil GT Performance Racing Oil 25W-50 engine oils.

Yah, buyer beware! Lucas Engine Break-in Oil Additive - TB Zinc Plus is good stuff: 31,000 PPM Zinc

That's good advice from Gareth. J. The wiring and connectors to the ammeter is a known source of car fires on old 240z's. The ammeter sees full system current all the way up to the gauge. Old corroded wires and connectors build up resistance across the connections leading to heat build-up, melted insulation/connectors and finally fire. I'd recommend ditching the ammeter for a voltmeter. You don't have to pull the dash and there are instructions how to do it on this site.

Awesome build! I'd recommend something different than the T3 front differential mount. That type of mount is known to move around under load.

Ah, I thought the holes in the throttle bodies we're injector holes. It may be ok then. The will still see some fuel so you might want to check them periodically.