Managed to grab a few photos of the installed p1 unit today
Seems like several of us are on the same path at the moment regarding coolant water heaters. I have two SR3's basically so that I can have some toys in the workshop to play with... racing just gives me a good enough reason to have them... So I went the full custom set-up - details below.
Referring first to my original post here in this thread, I ended up buying 2 x 1kw heaters from the same manufacturer. I think they were about $100 AUD each (~$60 USD... although probably double that now because of Trumps tariffs..??) . The reason I went that way was because one of the tracks we use here in Tasmania doesn't have power outlet in the pits... so we have to run off our own generators. My Honda gen will run the two x 250watt oil heater pads on the dry sump tank, and then has about 1.2kw 'spare'. A single 2kw heater would have meant I couldn't run the oil heaters and water heaters at the same time. So I decided to install two water heaters in 'series' and made them individually switchable. This has another benefit of giving me an 'installed spare' in case one of them ever burns out.
Fittings used were Jiffy-Tite 3000 series (purchased on eBay from an American supplier - these were the most expensive bit - around $400 AUD ($260 USD). I used 'push-lok fittings on the female hose ends, and AN8 on the male fittings that are on the engines radiator supply/return lines.
The pump I used was an identical Bosch pump to what is supplied with the SR3. One less spare to carry to the track... with this one now being the spare I will use if ever I have issues with the cars pump. I already had this on the spares shelf - can't remember how much it was... but I bought it direct from Bosch.
There's a transformer for the 240v to 12v supply to the water pump... purchased at a local Electrical store for $50 AUD or $30 USD
The box/enclosure was from a local hardware store (less than $45 AUD or $30 USD), and the electrical switches, terminal blocks and the silicon hoses were bought from Temu (ridiculously cheap and seem like ok quality - everything supplied with free shipping for less than $50 AUD or $30 USD)
Works great. The Jiffy-Tite fittings don't appear to be true 'dry-break' like Staubli or others. These release a few drips when you undo them under pressure (from the water system being hot) and therefore pays to wear some gloves... but they are a lot cheaper than some of the true dry-break fittings so maybe get what you pay for...
Water temperature rises from ambient (about 15C the day I tested it and same on the first race meeting) to 70C in about 45 minutes with both heaters running. It takes longer when running only one heater but still reaches 55-60C in an hour... and levels out at about 65C... which means that the engine/radiator radiates about 1kw of energy just sitting there and the system reaches equilibrium. This is quite useful as when the engine reaches 60-70C I can turn off one heater and the single remaining heater will hold it at ~60C until just before we go to the grid. My oil heaters get my oil to ~100C.. so both water and oil plenty hot enough. It's amazing how hot everything gets... a pretty good set-up to reduce hours of wasted engine time.
I should mention that I had to bridge out the internal thermostats on the heaters (took about 5 minutes to do) as the heaters are supplied with thermostats that are set to about 40C, and turn the heater off and on to maintain that temp. The heaters are meant to have thermostats that are set to 60C.. but both of mine initially cycled on/off at a much lower temp than that.
Photos of the completed setup.
Hope these help others who might be interested in a useful 'project'
@rjbender
awesome, the attention to detail and craftsmanship is exquisite!
thats fantastic, so (ignoring your decision to run in series), 1 1kw heater, Jiffy fittings, transformer, and electrical/water fittings for ~$650AUD = ~£320 GBP, + Bosch pump, probably another £100 here in UK. Essentially you've built something for £450 in my money VS an all in one pre built option here for £1000. That's a huge saving.
My issue is i don't have a clue about how you've wired up the electrics/switches. I know it's basic and i could probably learn it with some youtube vids, but i'd need a wiring diagram to follow really.
Here's the cheapest option I could find in the UK - https://race.parts/Catalogue/Set-up-Pit-Equipment/Engine-Pre-Heaters/Racetech-HeatBox-Engine-Pre-Heater
I'd love to follow what you've done but i have 0 knowledge on electrics and would need a step by step. I loaded your pic into chatgpt and here was the result:
@rojid sure have, from cold, on a cold morning, it hits 70deg in well under an hour, unit is tiny, self contained and very easy to plug in/remove at the start of the day and between sessions... would recommend.
sounds like a great system for the price. I'll have to ask them what shipping cost would be to UK.
impressive. The Racetech Heatbox thing available in the UK says it will only get the temp up to 50 deg.
Your unit looks so small and compact in comparison. I've asked them if they could deliver to UK.
@rojid - G’day. I’m travelling in the UK and Norway right now but will be back home at the end of the month. I’d be happy to share a wiring diagram with you once I get back if you’re happy to wait.
I am new to Radicals so please excuse my ignorance. I understand that the factory thermostat is removed in these cars. If the objective is to quickly get the engine water temps up, why can't we simply put the thermostat back in?
On the same topic, but related to oil temps, any issues installing a oil temp thermostat going to the oil cooler?
Thanks!
That would be much appreciated. It's going to be a hassle trying to import anything from US or AUS so it looks like self-build is the way to go.
It would be great if you could screenshot your order from Temu so i can see the exact components used.
I'm trying to draw your circuit out based on the pictures but it's difficult. Also don't I need to put some fuses in between the rocker switches?
I'm going to go for a single heater 1kw build instead:
Main components
- 1kw self circulation startup heater, around £50, 240v mains therefore current draw of 4.2A.
- bosch pump (same as on car) https://www.partsinmotion.co.uk/car-parts/cooling-heating/water-pump/bosch-secondary-water-pump-electric-water-pump-0392022002-detail?srsltid=AfmBOopAmCKH-SPKmcC1zhnypW--RyRr4O3VKwBr1xQPLkRJWeOtO7lJ £140
I can't find details of how much power this draws, what was the Amp rating of the DC adapter you bought?
Electrical fittings
- 240v AC to 12v DC adapter - unsure of Amp rating required.
- kettle lead to mains + male connector (IEC 60320 C14 panel mount)
- terminal block to feed power to both heater and pump via transformer
- fuses?
- 2x illuminated rocker switches, latching, SPST
Hose and fittings
- silicon hose length - what inner diameter did you get?
- jubilee hose clips
- dry break fittings male + female (either Jiffytite or Aeroquipe, seems like a cheaper alternative here in UK)
- 2x weld-on AN fittings
so it turns out the P1 heaters are what appear to be rebadged items with better fittings mounted to them. I found the exact same heater here, and the good thing is they do deliver to UK, for free. Presumably there'll be some nominal import tax i'll have to pay which for a product like this will be minimal, and VAT on top @ 20%.
Even so that still comes to around £150 only.
I've gone for the 1500w 5/8 version which means the hose is 16mm ID, 230v. I will have to cut off the plug and put a UK one on, easy enough. I found a positive review of the smaller model here, looks like it does a really good job as Luke as confirmed above also.
For the fittings, to save cost i've gone with smaller drybreak fittings, as the Jiffytite 5000 series is twice as much as the 3000 - £190 all in. I could not find a drybreak fitting that was below size -10 with a 16mm push-on end, only 13mm with a -8 drybreak.
2x drybreak socket/plugs, JIC -8 (i think JIC and AN are the same)
2x weld-on male fittings
And finally £20 for 2 metres of flexible heater hose and jubilee clips.
Should get the heater in a few weeks max - i will report back after testing.
@rojid ... good find and good progress. I will not bother sending you the wiring diagram you requested then!
I got back from the UK last week but have been ill ever since. I was at RLM for a week or so while in the UK and saw your engine there! They are fantastic people and will look after your rebuild for sure.
-8AN fittings will be large enough for this application and while I used 16mm hose I think 13mm will be OK too. The 3000 Series Jiffy-Tite fittings are the same as I have used. There shouldn't be any issues.
Rod
@Luke-ellis - the car is all up and running..and i have one final thing left to test. My preheater. What is the logic here -
- I'm assuming I need to have the car's pump on to keep things flowing whilst the heater is running, correct? Or is the unit's own pump powerful enough to circulate the coolant round itself?
- When i plug it in via the drybreak fittings will coolant just immediately start to flow into the heater and prime it?
i'm assuming it will given that when coolant lines are disconnected it immediately causes mass spillage! And then it's a case of leaving it running along with the water pump for 30+ minutes? which means i'll have to leave the car plugged into a battery charger too i guess to prevent battery draining whilst the pump is running constantly?
Assuming your heater unit operates the same as mine.
- the units pump is strong enough to circulate the heated water throughout the system.
- the pump heats very fast so I would not recommend running it dry at all ever
- when I installed mine I pre-filled the hoses and pump via gravity before tightening the dry break fittings on to the ends of the unit…you may be able to use the cars pump to prime it before turning it on but it’s a simple thing to prefill
- Thereafter it remains full and primed for each subsequent use (unless you suffer a leak from somewhere on the unit)
- Heating time varies with ambient somewhere 30-60m but it’s usually ready before my oil which has two electric heaters on the tank
- it has no thermostat to shut it off so will continue to run and heat until switched off
- as I don’t run the cars pump I don’t need to worry about draining the battery
it look to be a very similar design, certainly the body is exactly the same. I just don't have the fancy fittings installed on the in/out ends, so i've just jubilee clipped on hose.
sorry do you mean 'by gravity' that you just poured some coolant into the unit to prime it? the instructions are also clear on mine and says to absolutely not run it dry at all. Sounds like you've done what i was planning to do also - fill it with coolant then attach the dry break fittings on.
interestingly mine does have a thermostat, and will turn off when it reaches 65 degrees.
cool, sounds like a super simple easy operation then, and i don't have to run the pump. Can't wait to try it out tomorrow! i will report back.
