joshuaho96

Adjusting the idle screw is usually (emphasis on usually) just covering up deeper issues. Stuff like the cold start valve not closing properly. Throttle shaft seals on the way out. Coolant temp sensors getting out of spec. Coolant temp sensors especially can be a bear to diagnose because they can fail subtly. My dad just spent weeks chasing down his high idle. He cleaned the coolant temp sensor and everything but the resistance curve just drifts over time and if it's been 20+ years they also get super slow to respond as well. Has a massive effect on fuel economy as if it's off the ECU is going to run richer and command high idle for far longer than it should otherwise.

It's more like on average the things I see a lot of things going wrong. Yes, usually the people who reach out are the ones who are having problems but on average it feels like mechanics and tuners here aren't really competent. I swing between thinking my standards are just way too high and wondering whether people really are just this dumb. I just had the strangest 10+ reply argument on a Facebook group over someone insisting that the factory R34 GTT boost control solenoid reduces boost pressure to 5 psi when it's on and raises boost pressure to 7 psi when it's off despite showing the exact plumbing in the factory service manual and the solenoid behavior detailed in the FSM.

I say it often, none of this stuff is really Skyline-specific per se. But in general there's not a lot of people who actually know what they're doing. A lot of people charging like they do. Agile software development probably isn't the greatest idea for an engine controller.

For me at least the reason why it bothers me is because it's indicative of a deeper problem. And that will nag at me forever. Especially because I have tailpipe emissions testing + evap leak testing every 2 years.

The RPM is just a target, the ECU will adjust things to try and hit that target but it's by no means guaranteed. If the IACV duty cycle is 0 or something like that and it's actually closing up fully then the idle is as low as it can physically go without reducing ignition timing. The problem can be something like the cold start valve in the IACV not closing fully, worn throttle shaft seals, torn rubber diaphragm in the brake booster allowing unmetered air, etc.

If it's been tuned idle rpm can be changed.

The bumper you're talking about looks like this: Rear wing is this different version which is more GTR-esque:

That is the option code, not the VIN. Regardless all of that production is considered series 2: https://gtr-registry.com/en-ecr33-vin-table.php

Type "M2" means it's a series 2. I would not be shocked to learn that the production changeover was somewhat lax and a late 12/95 production car actually got mostly series 2 parts with a bit of series 1 leftover. Post the VIN and it'll be easier to investigate.

As a general rule removing rubber fuel hose is so difficult I would replace it if it hasn't been done in the last 5 years. The risk you damage the liner or one of the inner layers is pretty high if it's not almost brand new. BMW's recommendations around coolant hoses is similar. My R33's fuel hoses at the fuel tank were so perished that they were ready to burst FYI.

Yeah, that's what he's referring to as far as I can tell. His profile picture shows what he's talking about. Two fuel hoses at the front of the manifold but it's terribly zoomed in.

I really doubt there's a restrictor. Most likely it's just marked so you orient the hose if there's something special about it like sheathing positioned in a specific area to avoid rubbing a hole into it. Or they don't want you to mix up which hose goes where. The one with the filter goes to the fuel rail, then the regulator. Then on the way back it goes through the damper. If there was a restrictor on the damper line it would artificially raise fuel pressure and reduce the ability of the FPR to actually regulate pressure.

I have seen a case where the starter motor shorting against the casing caused a massive voltage drop + so much EMI that it caused all the sensors to spew garbage data at the ECU. Test the battery to make sure it has acceptable CCA/capacity first, I have gotten "brand new" batteries before that couldn't even power a 10W light bulb without dying probably because it sat in a warehouse too long without being charged. Only easy way to diagnose this 100% is put an oscilloscope on the battery and also look at key sensors to see if there's any clues.

There's a bunch of smaller shops that don't quite attract Singer money but are still hiring from that same pool of labor. Those are the body shops that you go to when you can't afford a Singer, but your old Porsche needs some serious bodywork. You can't exactly take those cars to the usual insurance body shops. When I say restomod, I mean they'll do something other than 100% OEM/OEM-equivalent aftermarket parts R&R. In the Porsche world this would be stuff like taking a 50k 964, doing a bunch of deferred maintenance/unwinding the nightmares the previous owners did to the car because a lot of people that own these cars tended to be penny wise, pound foolish types, then maybe some relatively simple off the shelf modifications to things like suspension, transmission, engine, headlights, etc. and you've spent 130k USD. When even the worst houses in the poor neighborhoods are worth 1M USD and the nice houses in wealthy neighborhoods are worth 3-10M USD suddenly 130k spent on a 50k car seems cheap.

If you talk to restoration/restomod specialists in the coastal US they will turn their noses up at 150k USD jobs. Things are mildly insane here these days.

My advice is if you need a big build done do it in Japan. The yen rate is so favorable and there are shops that can be genuinely trusted and not micromanaged/carefully monitored every step of the way. Garage Yoshida is obviously my preferred option but they're so busy these days and all interaction with new customers has to be mediated through BBL/Toprank now.

Yep, in my case as soon as I started hearing weird noises I backed off the tension until it sounded normal again. Delicate balance between enough tension to avoid that cold start slip and too much damaging things.

Everything I found online said never use it because it'll dramatically reduce belt lifespan. No, but I have seen excessive v-belt tension cause the audible bearing noise from excessive radial load in things like alternators. So don't overdo it. Ideally you set it to manufacturer spec using a proper belt tension guage. I tried the "clicker" type gauges but those cheap things are trash. They read way too low even when you're careful.

This is kind of where I've ended up for the most part. It's easier for me, easier for shops that don't have to deal with my weird criteria/picky standards, etc.

Once the belt slips it can very easily cause a cascade that encourages more belt slip. Check the pulleys carefully and see if the grooves have cupped. If it has it's time to replace the pulleys. If the rubber has glazed you also need to replace it. Shouldn't be shiny. From the factory there's a lot of exposed fibers(?) on a v-belt that will go away as it's broken in but some should still remain visible without sticking out significantly like a new belt. I went through this on my dad's Camry recently. It would keep slipping even after setting the tension higher, only solution was a new belt.

I know mentally you're set on the ATS clutch but honestly I'm a big fan of the Nismo Super Coppermix Twin. It's much cheaper and in some ways I think it's a better design for a street/circuit car.

Nominally yes but I’m not really at that stage yet. Outsourcing to Japan is also a relatively good deal at the moment because their currency has devalued much more against the USD. You would assume this but a lot has changed from the pandemic. Mechanics are in short supply and demand for fixing old cars has gone up from the cost of new cars. 250-300 USD/hr is not an unusual shop labor rate in California and you’re paying that regardless of whether the guy is competent or not. Coworkers have been quoted 3000 USD for a water pump and thermostat at a dealer on an N54. Oil changes went from ~75 USD to 150 on fairly normal cars like Civics. The cost of the oil and filter hasn’t even kept up with inflation.

I mean the other day I had to walk someone through diagnosing why their timing belt was walking off the cam gears. At least one of the issues was a bent tensioner stud. Local mechanics have found runout on the CAS mechanism causing weird failures. I'm also no saint here I've documented some of the things I've had to learn the hard way. Something I discovered recently is that my CA emissions catalytic converters weren't even welded correctly to align the downpipe to the main cat and they tossed the support bracket that goes from the transfer case to the downpipe to support everything there. I spend a lot of time chasing down these decidedly unsexy problems and the net effect is it feels like I never actually get to the original objective (flex fuel, VCAM, oil control, cooling, etc).

I think this is just a product of how the US market works for this stuff. Shops are expensive and there's no real way of knowing what kind of results you're going to get, people don't really have the institutional knowledge. I have heard too much at this point to really put faith in anybody "full service" except maybe DSport and they aren't really a full service kind of shop. If you go to the right place I have no doubt they'll get it right for you. Some locals have set it up right but the cost really is nuts and even now they're still fighting issues. And you know I'm a crazy person who thinks things like twin scroll, relatively short low-mount cast headers, PCV recirc to intake, recirculating BOV, right-sized for ~400 whp, MAF load, validating all of that to a standard comparable to OEM test programs, etc are relevant. For what it's worth, multiple local owners at this point have been stuck in a perpetual cycle of blowing a motor -> getting someone to rebuild it -> some missed detail causes the bearings to wipe and spin just outside of break-in mileage or drop valves or some other catastrophe -> cycle repeats. I usually only find out about this because I'm perpetually helping random friends with diagnosing car troubles, Skyline or otherwise. The single turbo stuff if I'm honest is mostly secondary, it just doesn't seem to achieve the numbers in the ~2000-3000 rpm region that I would expect given the results I've seen here or in Motive's videos. I don't really know what we're missing here in the US to be causing this. Lots of people like to emphasize the necessity of finishing the project first and foremost, but I'm not made of money and I can't afford to be trashing a 15k+ USD engine build with any regularity. Or spending my relatively limited garage time these days unable to triangulate problems because too much was changed all at once. Also, even if it isn't a catastrophic failure I would consider spending the cost of single turbo conversion with nothing to show for it to be pretty bad.

Among other things yes. Making sure to either use an oil pressure regulator or the right restrictor size for your oil pump/range of oil viscosities you intend to run, making sure you plumb the lines correctly, turbo should be placed such that it siphons properly even when the water pump isn't turning so you don't boil coolant in the turbo after shutdown, oil return should be low resistance and also preferably picking the one that is most likely to return to the pickup as opposed to some other irrelevant part of the pan. It's far from impossible to figure this out but I have seen people really, really struggle and if that's the case it's easier to just take the path of least resistance. To me, bolt-on twin turbos are a fixed cost whereas single turbo is almost unbounded.