MIP

Via the power of ball bearings, I did this last weekend: Link. Infact, I just put one of the two in, not sure why you'd need both.

I did a before/after comparison reading off IAT (using a kiwi wifi connector, and Rev on the iphone), over a 45 minute drive, logging after the car had come up to operating temp. Average IAT before: average 56C, peaking at 68C in low speed traffic. After: average 44C, peaking at 55C at low speed. Both results driving for around 45 minutes, it was a hotter mid afternoon ambient for the after readings.

coolchrisuk

I like the idea of this, especially ease of reversal for those extreme winter days/weeks we have been having!

eSeM

You really need a Hondata intake manifold gasket for this to work properly. That blocks the flow of coolant from the engine block into the manifold.

richmc

Ludite time MIP, what will this mod do? Honest question, just curious.

GavB

Rich, my understanding is that the throttle body and the idle air controller are part of the coolant circuit in order to warm them in winter and prevent any freezing. I am sceptical as to removing the flow could affect air temperatures in any significant way - there is not enough area for heat exchange vs the air flow rate, IMO.

eSeM

Even by insulating the intake manifold from the engine block and preventing the coolant flow through it the difference in air temperature is minimal.

MIP

Well, according to my IAT readings, it's a ~10C drop. The coolant going through the throttle body is what, 80-90C? The body and butterfly will pick up that heat, and I guess the air picks up 10C on it's way through. I think the car responds better after you've been trundling along at a low speed after this. Obviously the theory is that air density goes up as temps go down, so power goes up. But I'm not going to claim there's a noticable increase in power, I did this as an anti-heat soak measure.

I think a pack of 10x ball bearings cost me a quid. I'll probably go to loftus's technical day if anyone wants to try it. For the sake of £1 and less than five minutes, why not eh?

richmc

Still not sure I get this, but if you stop the throttle body being cooled surely the tempreture goes up not down. And as airflow goes up temperature drops, if air density incresses temperature goes up, like compressing air in a bycycle pump (or the compression stroke of an engine), there are more molicules closer together to create friction. I would think heat soak would be worse as it's caused by hot air entering the system at low revs and so at a low airflow rate.

GavB

You need to realise that although its called coolant, its only a coolant as far as the engine is concerned. As the circuit runs at 80Degc+ is a heating medium for other areas. Inlet air is at ambient temperatures and so 80Degc is considerabley hotter.

Airflow is not going up but Mass Airflow is if the air is cooler. Its not the same analagy as the bike pump as you are not putting in work to compress it, you just adding less heat and therefore the air stays denser.

RichwiththeS2000

There's no real "evidence" for it, but it is scientific fact.