250 relocating battery to boot

I think most people just lay the ecu flat, where the battery tray is

 

My car had this done before I brought it, use the battery bracket and attached that to the floor where the spare wheel normally sits (drill through to the underside). Then simply run a cable through the car into the engine bay. ECU is flat where the battery used to be.

 

Mine is a 225 so not sure if it's similar but I moved the ecu to the rear so I could use a bigger filter surround
.
Also gives a shorter, straighter intake to the turbo.

 

Im prettry sure its possible to move the battery to where the airbox is on a 250 rather than move it to the boot.

 

Yeh that is an option on the 250 however it seems a lot of waisted effort either way imo. The heat from inside the air box vs the heat of the engine bay, unless you can get creative with some sort of cold air feed. the turbo will warm the air when compressing it anyway. Standard air box with an updated panel filter works fine imo.

 

Aye, it is a wasted effort. People still bothering with the most creative 'cold-air-feeds' on these cars are not getting the point of turbocharged cars.

Anyways, I did the 'move battery to airbox' thing on my previous MK2 car years back, just for fun. Wanted to see if it could actually fit a BMC airbox this way; quite liked the sound it made. Anyhoo, here's a picture of it:



Anyways, if you just want a similar air filter system, just stick a cone filter on the standard turbo hose and get rid of the std. airbox. There's no difference with these 'cai' setups.

 

TymenJ sorry mate but your full of s*#t.
You moved the battery just for fun and to see if the bmc airbox would fit.
Why didn't you just take the battery out, try the bmc then refit the battery and just stick a cone filter on?

 

the alternative is to improve on the stock set up and saw half of the snorkel off the airbox (it reaches to the left of the battery box) then jam some flexi duct into it, tape it if you wish to seal out all hot air, then route the other end of the duct to the front of the wheel arch area. Cut a hole there for cool air to enter if you want too.

The stock setup is pretty remarkable at keeping intake air temps at a modest level despite the hot weather and traffic here.

For the life of me, i cannot locate the air flow sensor. Can someone enlighten me?

Depending on where/which sensor the ecu reads the final air temperature from, this will determine where we should focus more of our attention. Why? Because this is the reading that the ecu uses to decide ignition timing etc. Getting a lower baseline air temp (ie. cold air intake) is great but if the intercooler is overwhelmed by heatsoak or the sensor where the ECU reads the final temperature from is heatsoaked/influenced by hot surroundings then our effort is wasted. Is there a link to an online workshop manual to help with some research?

 

Intercooler will heat soak quicker if the turbo is sucking in 90 degree ( rough guess under bonnet temp )warm less dense air. The turbo will also need to pull in more air volume (warm air expands) generating even more heat for the intercooler to deal with.

 

The airbox on my 225 was ok but the factory pipework to it was tiny.
I used 3" ducting to replace it .
Don't know what the pipework is like on the 250.

 

At least you can go through puddles in it now without flooding the engine haha.

 

Agreed, every degree cooler is valuable. I guess it comes down to the return on investment in terms of effort, time and cost vs actual perceivable gains. Personally i believe the only time you'd notice any gains is accelerating from low speed or a standstill. When the car's moving at say 60kmh there should be enough cool air flowing thru but watching the RS monitor leaves a bit to desire.

I connected my Scangauge II today and drove around. It displays live data from OBD and the intake air temp it displays mirrors the RS monitor's intake temp display. Now, to find this elusive air mass sensor or intake air temp sensor and see if any heatsoak prevention can be added!

I didn't measure the mouth of the stock snorkel when i had the battery box out but it has a decent sized opening, to my eye it looks at least on par with the diameter of the accordion pipe. The entry to the airbox is not circular - it's oval shaped, but the mouth is circular with an air horn moulded. The accordion pipe also connects to a small moulded plastic air horn at the top of the airbox

 

The intake temp sensor on the 225 is just before the throttle. Don't know about the 250.
Best way to check the inlet temp on all these set ups is pre intercooler. Less heat going in will always be better.
I will be doing this when I get time.

 

I'm also going to measure boost presure pre intercooler too.

This way I can compare against my scangauge which measures post intercooler.

 

There is an air temp sensor in the middle of the post intercooler to throttle body pipe, but i'm not convinced this is the only one.

A live comparison of intake air temp vs post intercooler temp would be sweet!

Boost pressure before/after intercooler should be the same unless there's a leak in between

 

No there will be a pressure drop, due to resistance and air cooling.

 

What do you mean?

 

Its a glorified hairdrier with a cooler to chill to air on the cold side ..

 

Painting your intercooler black will help with heat soak while stood still!
Actually worth a watch!
https://m.youtube.com/watch?v=f1QL9veQaNg

 

Cold air intake isn't that important in a turbo car as you have intercooler. Also airbox isnt too as you don't have to worry

Anyway the intake manifold and throttle will heat up as well so IMO I won't spend too much money chasing a little bit cold air but improve the cooling and insulation.

Like you can have all your intercooler pipe heat wrapped, getting a bigger intercooler and new intercooler pipe, forge silicone induction hose. They are much worth to do.:cool:

 

Why make the intercooler and turbo work harder than they needs to.
You have a limited amount of air for the intercooler to cool so cooler in is better.

For any given pressure cold air has more oxygen than warm air so why pull in warm less dense air to start with?

 

I mean the little bit of cold air won't make an amazing performance gain. Pointless to spend a lot on cold air intake system instead of getting a nicer intercooler

And I don't think a cold air system shows a great outcome on dyno

 

Neither does the intercooler.
My intake cost £34 and a branded intercooler is close to £500. Bang for buck I'd guess it's better.

 

Isn't it mental to think that the techincal geeks at RenaultSport didn't consider relocating the battery to the boot or to re-configure the air intake layout during that lengthy design process.

Unless your car is now a full on FIA race car, I very much doubt you would benefit from doing this for daily road use. Leave it alone IMO.

Just my two pence. Carry on.

 

No sure if being sarcastic or not..................

Trouble with moving a wet battery is the trouble you need to go through to protect the occupants of the car.

 

It's also amazing they didn't think about giving it more boost or lowering the suspension.

 

I bet the technical geeks were too busy laughing when they fitted the same crappy intercooler as they did to the 1.9 diesel.

 

maybe I'm alit daft.

What happens if your battery goes flat and you can't unlock the boot for a jump start?

 

Use the connection under the bonnet.

 

Sarcasm intended.

 

Unsure on the mk3's but on the mk2's Iirc the air temp sensor is after the intercooler. I'm guessing your on the standard intercooler with those sort of temps?

 

Have a look on your printout at what temperatures you were getting whilst on the rolling road.I presume( & am willing to be shot down in flames), in the boxes on the right there is a AT & IT, i presume these are Air temp & Intake temp? Have a look at mine on the RS Tuning group buy thread.

 

Is that made by Airtec?