My rebuilt engine is a 1914cc (same as before but better, i’m assured), which i’m now learning could have some issues with overheating that cannot be fully eliminated by an External Oil Cooler (which I don’t have yet anyway). It makes sense for me to get gauges to monitor this, before it is installed, so I have benchmark readings after it’s been driven in. The rebuilt engine details are: •Crankcase = Autolinea (Aluminium) •Crankshaft = Scat 69mm -Balanced with Flywheel (lightened) •Camshaft = Not long duration -Machined to between 100-110 Engle equivalent —Think it was originally stock •Cam Followers = 1 piece -Previously 2 pieces •Pistons & Barrels = 94mm •Conrods = Scat •Heads = Empi (Aluminium) •Deck Height = 1.5mm -Down from previously 3mm •Heads = 50cc •Compression Ratio = 8.5:1 -Up from previously 7.3:1 •Carburettors = Twin Kadrons •Distributor = 123+ Tune -Standard HT leads •Starter Coil = Bosch Blue •Spark Plugs = Bosch W8ac •Starter Motor = Powerlite RAC525 •Electric Fuel Pump •Oil Pump = 29mm HD •External Oil Filter -Full Flow oil •Oil = SAE 15/40 •Alternator = 55amp •Exhaust = VS Sports -Changed from Yamaha R1 cans and a load of snaking rusted rubbish •Tinware = Complete and powder coated Everything is new except the tinware, crank case, carburettors, flywheel, pistons & barrels and camshaft (which I believed has had some machining). From what I can gather, keeping it well tuned allows the engine to run at its most efficient, therefore coolest...and this needs monitoring. The 123+ Distributor has a decent Oil Temp gauge, so that’s sorted. The 123+ also monitors Manifold Pressure. I don’t know how that enters the equation and if it renders any of the below unnecessary...or if it’s totally redundant without an ECU. Choices (possible combos) are numerous and on the VS Sports exhaust there are 2 Lambda Sensor points. So i’m considering: •CHT Gauge @ £45 -On Cylinder #3 https://www.mainline-sensors.co.uk/...e-gauge-vw-pyrometer-cht-5-meter-sensor-cable + •EGT Gauge @ £45 -Relates to AFR but doesn’t actually read it, yet still useful as an indicator of efficiency in terms of being Lean of Rich -Sensors cheap to replace —Not an ideal sensor location on the VS Sport. 4x further than recommended but at least at a junction of 2 cylinder’s exhaust flow https://www.mainline-sensors.co.uk/...aust-gas-temperature-gauge?variant=1190629065 (A good enough combo with CHT for pilots, apparently) + •Wideband AFR Gauge @ £150 -On the other Cylinder Head -A better location to take a reading than EGT -Bosch LSU ADV Sensor —Unit circumvents many issues of O2 sensor faults reported on other products (AEM, Innovate etc) https://ldperformance.co.uk/product/wideband-controller/ + •Oil Pressure Gauge @ £60 -Electrical rather than Mechanical https://www.demon-tweeks.com/uk/tim-oil-pressure-gauge-electrical-244425/ TOTAL PRICE = £300 The above mentioned gauges are all made in the UK and are a lot more simple than others from the USA market, which could actually make them more reliable. Price wise my configuration gives me a lot of different information. I’m hoping it’s possible to swap the EGT & AFR sensors between left and right Cylinder Heads every so often to gauge them both over time; giving me good baseline readings to monitor for changes. As far as I can tell, from initial research, they are all of use...I don’t know what is overkill though. I’m looking for early warnings of engine issues. I’ve read as much as my brain can handle for now. I think the gauges inform you if you are driving too hard (or climate conditions negatively affecting) for the engine to cope, but also over time inform you if it’s necessary to tune the engine - which they then become useful for doing so correctly. For the uninitiated, like me, it’s another expensive can-o-worms within a minefield at the bottom of a rabbit hole...with just a torch. Light the way and lead me outta this ...please, and thank you. Sent from my iPhone using Tapatalk
The 123+ oil temp seems accurate BUT it requires you have the app running and phone in view and that your phone successfully stays in contact with the 123 via bluetooth. IME it will not, the bluetooth is patchy at best. I'd go for a stand alone oil temp guage. The manifold pressure the 123 reads is for it's vaccum spark advance. EGT: Let us know how you get on, I should have EGT too.
Great. Thanks for that. I knew you’d tested the 123+ Oil Temp Gauge (seems to only go to 100• though too). Although I always have my phone on the dash (SatNav & Stereo), it’s good to know about the bluetooth connection. Stand-alone Oil Gauge it is then. I’m gona need another dashboard. Sent from my iPhone using Tapatalk
The other thing is even on quite a large smart phone those gauges are very small. If you make provision for a temp sender you could try the phone/Bluetooth first, it might work for you? Mine seems to make sporadic contact, if I sit in the back it works better. All in all the Bluetooth part is a let down. It probably works fine in every other type of vehicle - a rear engined 70's camper must be the worst scenario. I wanted to monitor the advance, that was a big part of why I spent the extra £ for this version. I hadn't noticed the temp limit, my oil never gets anywhere near 100.
My arms and legs aren’t long enough to drive from the bench, so i’ll definitely budget for a separate Oil Temp Gauge - hadn’t even considered the size of the dials! I bought the 123+ for the immobiliser too. Best activate/deactivate that from by the engine hey. Not that it currently needs immobilising whilst in bits. Seems most gauge kits are for the front engine market. That’s why the Mainline-Sensors appeal to me. They do up to 10m cabling. Also do bespoke ones. They aren’t pretty, but I can make a nice surround for them. Sent from my iPhone using Tapatalk
Looking good I can't be much help other than i've got two vdo gauges cut into the dash just below the stereo. Oil temperature dipstick sender (checked accuracy against a real thermometer). Oil pressure sender with two prongs one to tell the gauge the oil pressure and one for the oil light (i think). Rev counter is mounted in dash where some people have a clock.
More power = more heat. You don't slow down up hills because you are using that power and making more heat. Gauges are good value compared to engine repairs?
Just as a little aside here, if that’s okay... What gearbox have you got? Is a standard 3 rib still okay with the extra engine size (compared to the 1776cc)?
I think the general consensus is that the 94mm Pistons & Barrels suffer from a lack of metal and fins to cool effectively, so the heads get overly hot and won’t cool from the oil and fan. I want to drive the camper in modern traffic safely (not like a nutter ) and not have to worry about destroying it, so just figure that the gauges will keep me informed about the health of the engine. As Zedders said, spending a small % of the rebuild cost is preferable to another rebuild. I also want to learn how to tune it, so they’ll help with that. This is all AFIK...which isn’t very far - about to the front door from couch! A lot of you guys probably intuitively know what’s going on with your machines - noises, bumps, performance, spark plug residue etc. I just don’t have that knowledge and experience yet. Sent from my iPhone using Tapatalk
I believe it’s standard. Now that’s a whole topic I haven’t even read about. Sent from my iPhone using Tapatalk
Big cylinders have short cooling fins and they’re close together. The oil is easy to keep cool but keeping the cylinders (and heads) cool isn’t so easy. The bigger engine will make more torque at lower revs, it will climb hills easier but the load is high when the fan is slow.
A standard 3-rib gearbox will be okay, although the bigger capacity would pull a higher ratio CW&P – but it would slow the fan down.
Gauges are useful to show you if anything has significantly changed. Personally id start with oil temp and oil pressure and see how you get on. Oil temp suddenly a lot higher than usual - slow down immediately. Investigate further ASAP. Oil pressure suddenly drops, look in the rear view mirror to see if you are leaving a trail of oil down the motorway etc Exhaust temperature seems to be money for little benefit really. CHT temp may also be useful, i've never had them. I'd be thinking of the £300 on all gauges in relation to the price of a new set of cylinder heads for example. Gauges don't make the engine run any better, they may give you an early warning of potential issues.
Tuning wise id get it set up properly on a rolling rd rather than spend cash on a Air Fuel Ratio sensor/gauge.
I’d be thinking £300 is very little in relation to the price of a new engine. But I wouldn't bother with EGT – it isn’t a gas turbine.
It looks a nice engine, although a lightened flywheel is strange for a bus and I don’t understand one piece cam followers – did it have hydraulic before?
I agree but exhaust temperature isn't exactly essential, nor is AFR unless you can do something about it. Unless im miss remembering @PanZer skill levels he isn't going to be fine tuning the engine himself ? I'd be putting the cash into things that will make a difference. Once the oil temperature is known, then an external oil cooler may be more of a priority than an exhaust temp or AFR gauge.
Make sure you've got the "Hoover Bit" under the oil cooler, and fit a volute/velocity ring to the fan shroud while the engine's out (may find cheaper elsewhere). https://www.csp-shop.com/en/engine/fan-shroud-velocity-ring-119-025-171vc-30288a.html
