New (bonkers) Seight

[Dave Eastwood (Gadgetman)]

As with everything, you have to go with what you’re comfortable with.

 

i use an alloy tank, because I saw the damage it did to a members feet when a plastic tank split on the start line of a sprint, and scalding hot water poured down through the scuttle onto his limbs.

 

The irony was, I seem to remember he was taken to the same A&E where he worked, and his colleagues took the p*sis mercilessly, once they’d got him comfortable.

[Andrzej]

Understand, individual choice. Also had once hot coolant in footwell due to engine failure and immediate pressure buildup in cooling system. it was not so much fluid as it was via cap, and luckily was wearing thick suit and high shoes. That is why I proposed new header tanks rather than old ones from used cars of unknown history. 
(in my case more dangerous was that my foot slipped from wet clutch pedal under brake pedal and I could not brake for a moment, and there was 180deg turn in front 😕
 

 

[AwB]

On 14/07/2025 at 20:38, Andrzej said:

in fact hard to see those readings from seat ,  maybe its for service / dyne etc. 

I don't like aluminium tanks — you can't really see the coolant level or condition at a glance. 

Maybe you could fit a Clio II header tank ? — it's popular and proven in kit cars. I use it in two of mine: a BEC MNR  and a road-going Westfield. But in this engine bay mighht be not enough space for it. 

Going back to the digital read out, I should have added that it was actually a digital thermostat for both oil and water cooling rad fans.  Quite a neat solution, as you can set activation temperature and hysteresis values.  The box is DIY and includes two xh-w1315 (AliExpress special) kit control boards together:

 

https://electropeak.com/xh-w1315-high-temperature-digital-thermostat?srsltid=AfmBOorMKrdA1GJeX1nspiAbpJLXNow6hqS-zdJ2-EXh4giarw-8U1Bf

 

But… I’ve run into a problem.  At some point during a run, the box stops controlling the fans, shows a very helpful error code (E1) and temperatures shoot up when slow moving. Luckily there is an override switch for the water radiator at least.

 

I think I have worked out why - the on-board relay is rated at 10A, and the previous owner had upped the fan to a whopping 16” SPAL (https://www.performanceairflow.co.uk/itm/16-407mm-Fans/SPAL-16-407mm-Cooling-Fan-VA18-AP70-LL-86A-12v-1918-cfm-Pulling/30102120A), perhaps without considering that it’s rated current draw is 18A.  So the cheapo boards might have some form of thermal protection kicking in.

 

So I have two options: 

1) use the existing box to control higher rated relays for fan switching (more wiring spaghetti)
2) change the fan control setup completely.

 

What do others use to control their fans and fan speeds?

 

I quite like the idea of converting to PWM control, as the SPAL on a simple on/off switch sounds like a jet engine (on top of the V8 grumble, the blower, and K&N intake) but I don’t really want to overcomplicate an already tightly packed area. 

[AwB]

On 14/07/2025 at 18:23, LoneWolf said:

Can't go wrong with ProAlloy if that's in your budget 👍

Black alloy header tank arrived and waiting to be fitted!  Very well put together and looks the business.