Hi all ,
Am running a japspeed fmic and looking for a new indication as the hks am ruining is having very bad heat soak . What kit will fit along side the japspeed fmic ?.

 

How do you know about the heatsoak? Do you measure intake temperature?

When the late, great Harvey Smith looked after my rebuild, we fitted a temperature probe and digital readout (in the cabin) into the intake just before the throttle valve. I have another that measures under bonnet temps at the air filter.

The intake temp is usually DOWN on the filter, despite the air having been compressed and passed through the turbo. Under bonnet temps are not startlingly high anyway.

 

The air filter is very hot . Under bonnet is also very hot . The filter is hot to Handel too ,
Put a code reader in and it up up high intake temp ?

 

The only temp that you need bother about is at the throttle body.

If your intercooler is working properly, it'll be fine. To check buy and fit a temperature probe into the hard intercooler pipe just before throttle body.

 

I still use the japspeed pipework and Im using an rcm induction kit. Fits in fine and after several rolling road runs and 3 different kits its the filter that flowed the best / made the most power.

 

I will have to check that with the probe ..

The code reader say high intake . I have changed the maf and the engine warning light come off for about 20 min ,
Drive the car hard and over 4000rpm on full boost the engine light Gos off . Come off boost and the light back on ,?!

 

Get yourself 1 or 2 , 2 meter K type Thermocouples ( 2 pin bimetalic ) from an electronics shop and a mulitmeter. See Wikipedia "thermocouple" for a picture of what I mean , stick the thin wire into the intake / Pre or Post intercooler, clamp it up so it cannot leak and run it back into the cockpit and then monitor it in traffic / whilst driving. You will soon see that movement at >30 mph will rapidly reduce intake temperature. The issue that you can influence is to keep the hot air emiting from the engine bay away from the intake , a number of methods exist , and I would advise you measure the delta each time between outside temperature and post intercooler intake and drive at 30 mph to see if your modifications have made any difference. Basically if you are slower than 30 mph heak soak will be a problem, there is only the IC water spray option , or some tried additional fans to combat that. I switch my Radiator fans on manually.

 

I forgot to mention that the tip about the throttle body is a good one , take the water feed off this and plumb it direct to the output side , you might need to re-connect in freezing fog enviiroment to prevent fuel carb freeze though.

 

Ahh, the good ol' venerable 'wimp switch'.

I wired one up on my old R5 GT turbo.

 

Is the throttle body mod worthwhile?

 

If it's a hks mushroom filter, then throw it away as they are rubbish and actually loose power mid end. Most are fakes anyway

 

Car is sorted. .
Hks replaced and is running fine

 

This is a how long is a piece of string question. But I will put it this way , during the summer (Germany) I never get a fuel freeze , but on a foggy November day and around 2 or 3 degrees C or less it will start to cough and splutter. Which is why Subaru designed in a manifold preheat.

I suppose the clever way is to plump in a bypass with a couple of stopcocks , but Im lazy , I just use a longer bit of pipe and move it over come October.

Is this mod worthwhile ?

In theory anything that keeps the fuel air mix cool
(more dense) is going to mean you fill the cylinders with more air fuel mixture.
So trying to keep the heat out of the intake system is just another way of supporting the Intercoolers job.

You will notice that some on here use extra spacers out of a Glass fibre / bakerlite type to insulate the cylinder heads from the intake casting under the tumblers, the heat transferred from the heads is considerable and inextricably this heats the fuel air mix before entry to the chamber. Im not aware at what sort of power / heat level these become really useful , I imagine the soak problem contributes to engine mappers often finding higher peak horse power on the earlier RR runs despite other tune improvements and use of huge fans to keep airflow moving. So what have you got to lose by deleting the intake heat pipe ? , seems almost a free way to maintain the power you have.