hjtrbo

I redesigned the board to allow for 3 stepper motors, additional IO and changed the colour to match the MCP module off ebay. I used a spare PIC to act as the can bus master to simulate random data. This setup is for a Link ECU. I doubt it would take much (if any) modification of the source code to make compatible with Motec. The terminal blocks to the right of the board are provision for switches, shift light, warning light etc etc. All working now. Car is still getting built so will be a while before they are installed into the dash. A short video of them working...

Progress is going well, but I wanted to update the thread with some learnings that I would employ in hindsight... For 12V reg use LM2940 (thanks to alexj for suggestion) No need to remove the air core meter and muck around replacing it with a stepper. Consider this method: Instead, cut the resistors off the internal meter terminals, then bring the 4 terminals outside of the gauge body. Then wire them to a CS8190 Precision Air-Core Tach/Speedo Driver with Return to Zero IC. Hope this helps others on their google knowledge surf.

I didn't know there was such a thing. I come from an industrial machinery background. I'll check them out. Thanks for the tip man :)

Ok, got the first board soldered up. The canbus module (blue board) then piggy backs onto the board. Still waiting for the mounting standoffs to arrive. The 4 way terminals are for 2 x stepper motors (2 gauges are supported per board) & 2 x current sinking optically isolated general purpose IO (e.g square drive for RPM or speedo, ECU fault light, shift light etc etc.) The 2 way terminal is 12V in, and the 3 way terminal is for programming the PIC microchip. There is a jumper to select between run and program modes. There is a 5V on board regulator with high frequency bypass pass caps for the IC's and large 2 x 470uF decoupling capacitors to help provide a solid power supply to the board. Reverse polarity protection is by the simple inline diode method. Still got to get the gauges assembled then hook it all up for a decent test.

You don't need extra senders etc on the engine for multiple gauges. Just pull the data out of the ECU. Saves a few hundred dollars and it's fun to learn about something new. My boards have arrived from China. Will be soldering them shortly. Will post pics and you can pm me if you want to buy one.

to make a can bus gauge

OK, good progress. Data is getting sucked out of the Link and the stepper motor moves. Just got to link the two together in software with a bit of scaling and position tracking, add a bit of glue in the back of the gauge, press on the needle, and she's done! DIY can bus gauge, best $30 (so far) ever spent. https://au.rs-online.com/web/p/microcontrollers/8802680/ https://www.ebay.com.au/itm/MCP2515-CAN-Bus-Module-TJA1050-Receiver-SPI-Module/302496093646?hash=item466e2c15ce https://core-electronics.com.au/automotive-gauge-stepper-motor-x27-168.html

OK, good advice. I pulled apart my VDO moving coil gauge. Looks ripe for one of those steppers. Let me play and i'll update the thread in due course.

Hi all, looking for suggestions, I'm hooking into my Links G4 can bus with a home brew module consisting of a PIC micro controller + CAN controller / transceiver that will give me up to 8 x 0-5V analog outputs and a few digital in / outs. Sum total of parts $15. (Programming and development..... lots of hours, but my time is free) I have tested a VDO oil pressure gauge and I can successfully mimic the operation of the sender via PWM and 1st order filtering to a transistor that provides the current sink for the gauges sense terminal. It's not an elegant solution but it works. What I am looking for is a gauge that takes 0-5V and is available in a range of common display types like oil / water temp, oil press etc. I've been googling around, but nothing is coming up? I have seen dedicated canbus gauges but they are so overpriced and I am not sure if the Link CANBUS operates to a particular automotive standard for its peripherals that I already have hanging off the bus so they may not work. Any suggestions for 0-5V or something similar?

OK, just found this to help out with a few of the questions raised from my above post. I'll pass this on to the builder for him to follow up.

@Ben C34 yes you are right. The build direction changed half way through. The build has been a slow process, just getting stuff done as the cash and time comes up. The turbo will be the limiter in the final power output and may need to be changed as the tune works away from the base values. @GeeDog I'm going to need to be educated here. My engine builder has extensive experience with V8 engines, however I believe this to be his first RB build, so he will not know the little tricks that need to be done. 1a. Extended oil pump drive collar? I'm still on the factory oil pump. Is this still needed, or is it to future proof me if I upgrade the oil pump? 1b. Never heard of changing to grub screws? Why do people get this done? Benefits? 2a. Return oil channels drilled larger? Got me buggered there... Education please? 2b.Piston to bore clearance already checked and within spec. Cylinders measured up sweet, just given light hone. Standard size pistons were ordered 3. Already bought the injectors. I'll unfortunately have to suck it and see. You can say I told you so in a little bit 4. Will be close to $70k by the time brakes, cage and paint is done. You are so right. I originally budgeted $25k. Next time I see a car for sale that in bone stock factory form is only worth $20k, but it's sale price is $60k and it had $90k spent on it, it's a bargain for the new owner. 2b, 3 & 4 can be put to bed.

Mild modded S1 RB25, please check my parts list for completeness Hey again, Nearing the end of the shopping list for engine. Would a couple of the experienced members here mind commenting on what parts should be purchased in addition to what is listed? If it isn't listed then it's still OEM. All listed parts have already been purchased. Chasing 250+rwkw through a RB25 box. Base engine was an unmolested R33 S1 RB25DET with 120,000km on the front half clock Bottom end Exedy HD button clutch (NSK-7056HDB) Exedy lightweight flywheel (NF01) Crank balance Block acid dipped, checked, decked, honed & frost plugs ACL main / rod bearings (7M2394HSTD / 6B2960HSTD) ARP main stud kit (202-5403) Manley H beam rods (14028-6) CP pistons (SC7307) Head, Intake & Exhaust Cometic MLS head gasket 1.3mm (C4318-051) ARP head stud kit (202-4301) Franklin Cams - Stage 5 Re grind (Adv 272°, @050" 205°, Lift 330") Franklin Cams - Valve springs HKS timing gear exhaust side (22004-AN002) 550cc Injectors (Can't remember what brand they are) Greddy front facing plenum (13522316) with standard RB25 throttle body Flea bay 600 x 300mm intercooler 2.5" alloy intercooler piping Plumb back BOV Factory turbo hi-flowed (Biago internals & housing machine, don't know flow specs) 3" Straight through exhaust into Turboflow resonator (Cats still to be sorted) ECU Link G4 Storm (launch control, anti lag, spare I/O, can bus) Fuel Surge tank Bosch 044 pump There are some obvious omissions such as oil pump & cooler, water pump, harmonic balancer. The plan was to leave those parts as OEM. Lads & ladies, again, I only ask for comments from people who are experienced with regard to parts that should be added to this list.

Thanks for the offer, i'll keep it in mind It was tempting, but so common now. I think a lot of people will be surprised when they hear an HJ boosting past with that unique Skyline note.

Review time 4.62____ track day 4.3_____border line on to short for cruising at 115km/h 4.11____maybe 3.89____likely 3.7_____To tall for the track 3.55____Getting into the Falcon ratios Staying with 3.89 so far. If I hate it at the track, I will have no choice but to buy a 2nd centre which would likely be a 4.62 (266 km/h @ 7500rpm on 245/45/17's). Downside is spending Friday nights before Super Sprints draining diff oil and swapping out centres and then getting to reverse the process on Sunday night. Thanks for all your input guys. It has helped me narrow down the list.

I'm in Trafalgar VIC. I don't know anyone with a Skyline. All the boys love diesels down these ways lol. Yes, if I could understand how this engine goes with stock gearing is that would be perfect. My background of car ownership is a long line of Holden and Ford V8's and XR6T's, so i'm used to 1800 to 2000 cruising revs. 4.11's aye, back to the spreadsheet again. And your comment similar to "a jack of all and a master of none" is exactly what I am chasing here! Well said.

@admS15 it's in a HJ Holden Belmont Ute. Weight is approx 1450kg + driver. Turbo is a hybrid setup, OEM housing stripped / enlarged and Biago Turbo parts put back in. Happy at around 18PSI the builder tells me. Not sure on flow rate.

Hey @adms15 Yeah I got the RB25 box, haven't purchased diff gears yet. The ball is rolling on the rest of the diff. Most bits are locked in, i.e Eaton true trac centre, housing width, suspension pick up points, brakes, bearings, axles etc etc. Only thing left to work out is the ratio (which I'm gonna think about for a week) Again, just trying to chase a compromise between the highway cruiser and track. That said, when the car hits 5th on the straight at Phillip Island, I don't want it to die in the arse. This car will never ever be racing for sheep stations. No one is saying NOT the 3.89 so thats good so far...

well written opinions lads, thanking you

@Steve85 I'm looking for compromise (illusive). This car will see track time, just as much as it will see street time and club events. What do you think about the revs your are pulling when cruising at 110 on your car, I mean, do you think they are too high and / or the car lets you know it, or is it fine? Look at the idling speed of a F1 engine 4000+ rpm lol. I'm just trying to get a feel for how these engines are on the cruise. And yes, dyno is the best option to gauge, however, it's a bit hard without a diff lol (access to chassis dyno only). Just trying to see if I can actually get a car part right the first time.

Diff ratio opinion on driveability at 110km/h Hi all, In the middle of a custom RB25DET build and have yet to drive a Skyline. Its diff ratio selection time, the options I have are the standard Ford 9" ratios. The engine has not been on the dyno yet, but has forged bottom end, hi flow turbo, injectors, mild cams and a programmable ECU so I do not know what it is like down low. I need to know if 3.89:1 will be ok on the highway in the 100 - 120km/h range. More to the point, are these engines completely hopeless at around 2400 - 2800rpm? If so, then I can go 4.11 which increases the RPM range to 2500 - 3000rpm. Anyone running a ratio different from factory please may I have your opinions on how you find the day to day driveability on the open road?

Problem is the search feature is so good I don't need to post questions, and I don't trust my own advice let alone passing it on. Thanks for letting me back on.

Hey again, Someone didn't like my methods and cancelled my user name. Any how, same add as posted yesterday. Just need a box for a mock up. Around $100. I can pick up 200km from Clarinda VIC. Please don't PM me. e-mail to [email protected] or 041 282 3727