Picked up another S recently and it has the following mods, which I am reviewing:

- Spoon thermostat
- Spoon rad switch
- Spoon radiator cap
- cut-away in air scoop
- Spoon throttle body

The engine runs regularly at 2-3 bars and here in the UK we have annual day-time temps of 0*C to 30*C. From reading around, it appears that replacing the thermostat is reasonably important - I don't track the car anyway. So if I decide to replace the thermostat, which of the other mods should I keep on, which should also revert to OEM?

Your reasoning behind it would be appreciated too.

Parts below are OEM that were given to me with car - I also have an OEM rad-cap


Cut-away air-scoop - I have a new OEM available


Cut-away in-situ with "funnel" to air-box

 

IMO, get rid of the Spoon cap, thermostat, and switch, all of those work together so I'd keep them as a package and sell them off. On the AP1's you want to be at 3 bars when fully warmed up, if you're going between 2 and 3 bars your engine is running too cold.

 

I have the Spoon thermostat, switch, and cap running w/ a Koyo and Hondata IMG and it's been running to cold, and I live in Hawaii! Infact, my CEL popped up a couple of times and it said that coolant tempature was too low or something. Might have to switch to the Mugen cooling mods!

 

The cut in the air guide will reduce cooling capacity as less air is forced through the radiator.

 

dunno which to keep or which u should sell, but i must say, whoever did the cut away scoop and air funnel did a very clean job. I also have the cut away scoop that i did on my own, but i put a mesh wire to keep bugs and rocks from getting sucked in.

 

At the moment I'm now planning on re-fitting the thermostat, rad switch and rad cap, which brings it back to stock in that respect.

Air-scoop (Washabi et al): I'm curious to know how much of a change in cooling the air-scoop cut-away caters for, i.e. is it "significant" or within "tolerances". and does the cutaway potential have merit in allowing more cold air to the air-box? OR is this so neglible that I should re-fit the scoop and look at also removing the little "funnel" to the air-box itself?

 

i actually don't really know if it makes a difference in heat or performance... I did it when i just bought my car used and was bored looking for a DIY. It is supposed to allow more air to travel upwards through the plastic guard and funnel into the intake though. I gutted my intake box as well, but it's effects are negotiable.. many say it allows the intake to breath better, whereas some say it disrupts the flow of air directly to the intake filter take your pick. I would just keep the funnel because it is a nice piece and it makes logical sense in the way that it was designed for maximum airflow into the intake box. I also have a Koyo radiator, and having the cutout in the plastic hasnt seemed to make a difference in my cooling system. as for power gains with the direct airflow to the intake, i could not really tell the difference, I just assumed the modification as a little bit of reassurance that the intake isnt choking for cold air.

 

The air scoop is fine, allowing some flow not sunject to radiator heating. Any concern would be the cut air guide which allows air to easily bypass the radiator rather than being forced through it. I don't know that anyone can quantify the difference but we do know that most of those that completely removed the airguide had some overheating issues.

 

Thanks for that - found a rad-shield thread which was pretty useful. I've never heard of a UK car reaching 4 bars because of the temperature here, so to some extent I might never know whether a cut rad-shield makes any difference.

But at the moment? I'll hand over the new rad-shield when I send the car in to have the thermostat/switch/cap replaced.

So the final question is the throttle body being re-fitted. I'll start another thread for that.

Thanks for all the input so far guys (and girls perhaps!)