GTSBoy

Apples and donkeys. The R32 speedo is mechanical. How does a spinning magnet in a cup turn the cup twice as hard as it usually does?

That actually sounds worse!

What else have you done just before that? Don't say "nothing", because dead shorts don't appear from nowhere.

Hack up and epoxy bodge job? Nasty.

I just wanted to bring this slightly back on track, and also disagree slightly with Tao. If Tao was talking about the Z32 AFM in the cooler piping - I would not do that. The old Hitachi plastic tube AFMs are not supposed to be put into pressure pipework. They are not really mechanically strong enough for it. The modern card style AFMs are easy to fit to pipework and everything about that installation is strong enough to handle boost.

Yuh, so while I'm usually the guy explaining how the speedo and related shit works, I recently experienced something which blew my mind and I can't think of how it happened. So, I'm casting it out to the braintrust to see if there's any reasonable explanation. Here's the story. I drove the car (R32 GTSt, R33 turbo gearbox) away from home, and the first time I noticed the speedo was once I was out onto the 60km road about 1km and 5 turns from home. I'm doing maybe 60 km/h. The speedo is reading ~120 km/h. I'm all "WTF is this?". I roll down the road and out onto the 80km section, where the speedo is gleefully telling me that I'm doing at least 150, even though I'm pretty sure I haven't even caught up to the mix of sheeple and mad dream boats doing anything from 70 to 100. I accelerate to see what happens and the speedo happily winds off the dial at 180. I stop at some lights. Take off, and......the speedo is back to normal. The brain is doing about 500 km/h trying to work out how this could come about. The R32 speedo is a cable drive. The connection is purely mechanical, right up until you get to the spinny magnet and drum bizzo in the speedo head. It's not like there could be an electronic fault that was double sensing rising and falling edges of the waveform or anything like that. The cup in the speedo head had to literally be getting dragged around against its spring with enough force to make it read about double what was really happening. So, has anyone got any brainwaves as to what the bloody hell could cause that to happen in the real, actual, physical world? The speedo drive was built from a Navara drive about 10 years ago when the car's big birthday transplants happened. The drive cable is only a few years old, having snapped after ~25 years of service. The back of the speedo housing is hale and hearty, no bits broken off IIRC.

Yeah, like, just drill holes from the discharge point of the compressor wheel back to the inlet.....nah that won't f**k up the compressor efficiency at all. It is not a smart thing to do.

Rotary idle brap tune brah.

Who knows? depends what's not right. The real problem is that it is currently working even though something is not right. That means that you have something else not right to compensate. So, you might at some point in the future make a change to something that you would have no reason to suspect would cause a lean out and destructo, but because of what you have now being twisted in some way, puts you at risk of unexpected destructo.

Why would you want to f**k with the efficiency of the compressor in that way?

Yeah, it's not fine. Might be worth a little dig to see if it's going to come unstuck at some point and ruin your day.

We don't all live in the soviet socialist republic of Andrewsistan (formerly the republic of Bracksistan) Greg. The rest of us can get away with a bit of dose. Even if it is totally juvenile.

The qty of energy lost off the turbine housing compared to the qty of energy flowing through the turbine and doing work is.... a tiny fraction. People worry about things that are not real.

No. Is there a strong vacuum signal on that vac line on the pressure reg when you pull it off? If there is not, suspect the source. If there is, then suspect the reg. But something is defo f**ked.

Note my nope is in response to OP question, not Murray's point.

Nope. It is an air mass flow meter. It will measure the mass of the air, regardless of its temperature or pressure (OK, within sensible temperature and pressure limits) regardless of where in the intake tract it is place. The air mass rate being sucked into the turbo is the same as the air mass rate being blown out of the turbo, at all times (ignoring during blow off valve events).

Put it in the cold side pipe from the intercooler and win at life.

And if you do not follow the above advice, please at least f**k off the 1920s vintage Z32 AFM in favour of a modern card style one.

And besides which.....anyone who gives their turbo a hot breakfast then shuts it off hot deserves it to get coked up.

Colour me confused. How can you remove the dampener to see what the idle pressure is? I feel that you are confusing the wording or the physical location of these devices. The dampeners are upstream (and perhaps on) the rail. The reg is at the outlet of the rail and is the very last physical device in the fuel system other than the return line to the tank. Do us a favour. Locate the real, actual pressure reg. Remove the vac line from it and tell us the idling fuel pressure then.

Why no twin EFR7163 or VK56 or LS3 transplant options?

Coking is not a thing on a running turbo that has cooling (ie sufficient oil and/or water flow).

It would take someone to be familiar with how much volume of fuel flow they expect to see out the back of the reg at idle load to b able to tell if what they were seeing was normal or not. The correct way to diagnose fuel pressure problems is to plum a fuel pressure gauge into the fuel line in the engine bay before the fuel rail. Anything else is just guesswork. And, by the very definition f being a back pressure regulator, the fuel pressure regulator, if undersized for the pump (or, perhaps a little blocked) will cause high pressure at idle and maybe low pressure up top. The low pressure not being the fault of the reg, but of the pump or other restriction on the supply side (not the return side).

EMAP is exhaust manifold pressure. Boost is inlet manifold pressure. For making really good power, you would prefer EMAP to be lower than the boost pressure. When EMAP exceeds boost pressure, it adds more flow restriction to the engine, driving more reversion of hot exhaust gases back into the cylinder, which just generally makes absolutely everything about trying to make power worse. 1:1 is an expression of the ratio of EMAP to boost pressure.

I can't imagine that the repair/write off status would make it any harder to re-register than otherwise. Butt I can't peak for any state that has this pink slip blue slip bullshit. Here in SA we do things the old fashioned way. Regency identity inspection followed by Regency technical inspection followed by "fix this list of shit and come back".