[johnscales]

Hi all.

I'm in the process of ordering the necessary parts to make MR.5's CAI to complement my JB4.
Has anybody (particularly in the UK) done this mod and if so can you let us know of your experience during/after the mod.
Also, just out of interest does anyone know for sure if there is or if there should be a significant difference between using 2.5" or 3" ducting?

Thanks

[johnscales]

Anyone in the UK even tried this?

[Josh1a1h]

Save your self time and hassle.

Just get a BMS DCI, simple and you can always revert to stock later

[johnscales]

Thanks for the input Josh1a1h. I've heard a lot about power not being consistent betweent initial staup and normal running temp.
If you (or someone) can confirm this not to be true then I've already got dci coming (though not BMS) and will happily use these without the exta plumbing required. But if it's true then the cai is definitely the route i'll be taking.

[Josh1a1h]

What tune are you running?

[CustomColours]

In all cases of open cone filter s sat in a hot engine bay there will be a bit of heat soak. The cooler will normally put up with most of this. The best bet would be a cai but most running dci seem to have little to no issues.

[Josh1a1h]

A decent intercooler will solve your intake issues.

I am in the process of adding extra ducting from my front bumper vents to my DCI.

[nicktyler]

Does it really make that much difference? I was under the impression that a drop in filter is sufficient up to 450bhp+

[johnscales]

@Josh1a1h "What tune are you running?"

JB4 Map1.

I'm looking to go map2 with the bare minimum of dci or cai if logging shows that the car is able to take it. Catless or more likely sport cat dp's will come later. My research has turned up that there are a fair few people who have been running map 2 with dci only and a few specifically stating that they have been doing so for over a year with no issues. I'll keep logging anyways and will have upgraded the dp's within the next 3-6 months.
Since the introduction of the JB4 I have already noticed that the oil temp settles around the 120 mark on the same journeys I used to do where it would sit between 1 and 2 notches less although a heavier foot goes some way to explaining that also.
I'm aware that an upgraded ic would be an equal if not better buy long term but we're talking upwards of £700 versus less than £100 for a nice constant stream of cool air + an extra 10 - 15 ponies with more consistency than dci to boot. The ic can wait for now.

[Josh1a1h]

Originally Posted by nicktyler

Does it really make that much difference? I was under the impression that a drop in filter is sufficient up to 450bhp+

Drop in filters are fairly restrictive.

Although a DCI pulls hot air in from the engine bay...they are not restrictive, which aid the turbos in generating boost. The less hard the turbos have to work, the more efficient the turbos operate.

Originally Posted by johnscales

@Josh1a1h "What tune are you running?"

JB4 Map1.

I'm looking to go map2 with the bare minimum of dci or cai if logging shows that the car is able to take it. Catless or more likely sport cat dp's will come later. My research has turned up that there are a fair few people who have been running map 2 with dci only and a few specifically stating that they have been doing so for over a year with no issues. I'll keep logging anyways and will have upgraded the dp's within the next 3-6 months.
Since the introduction of the JB4 I have already noticed that the oil temp settles around the 120 mark on the same journeys I used to do where it would sit between 1 and 2 notches less although a heavier foot goes some way to explaining that also.
I'm aware that an upgraded ic would be an equal if not better buy long term but we're talking upwards of £700 versus less than £100 for a nice constant stream of cool air + an extra 10 - 15 ponies with more consistency than dci to boot. The ic can wait for now.

I would never risk map 2 with just an intake.

Just run map 5 and the tune will run the maximum safest amount of boost for your setup.

Only run map 2 when you get Downpipes...but i find map 5 trumps all if you are not running meth and basic Bolt ons.

[nicktyler]

Time for a cai then I guess...

[idnan]

Originally Posted by Josh1a1h

Drop in filters are fairly restrictive.

Although a DCI pulls hot air in from the engine bay...they are not restrictive, which aid the turbos in generating boost. The less hard the turbos have to work, the more efficient the turbos operate.




I would never risk map 2 with just an intake.

Just run map 5 and the tune will run the maximum safest amount of boost for your setup.

Only run map 2 when you get Downpipes...but i find map 5 trumps all if you are not running meth and basic Bolt ons.

+1 to all of that. Especially on the map 2 comments. Put it on map 5 and let the JB4 do its thing. On a warm day you might find map 2 causes timing drops despite being fine when you were data logging on a different day.

I'm not big on CAI on turbo cars, after all the air has to pass through the hot turbos then through the intercoolers before it gets to the throttle body. By that time the drop intake temp has been completely negated by the inefficient OEM intercooler.

You'll gain far more consistency and lower IATs at the throttle body with a proper FMIC than you could ever imagine with a CAI. I actually had a proper AFE Stage 2+ sealed intake which I sold on here not long ago as I couldn't see enough of an advantage with logs or through the butt dyno.

[johnscales]

@nick tyler : Time for a cai then I guess...

+1.... Then an intercooler.
Guy's, have a read of Mr.5, extensive testing at the bottom of another member's thread here (if it's allowed) :
http://www.e90post.com/forums/showthread.php?t=549965
He's tested it against dci and stock and the results are pretty conclusive.
I think that if you're already into modding it's got to be worth doing as it definitely improves the power already afforded by the jb4 and having read all the above link info plus taken your input on board I think i'm going to have to go for it.

[johnscales]

Just thought i'd do a quick update and rather than start a new thread because it's been done to death already. I'll just say that initially i've gone with dci for now and may be sticking wth it for some time.
Made my dci up for £40 and I am absolutely blown away by it. I switched my jb4 from map 1 to map 5 so that it can decide for me what's power the car can 'safely' put out and used my usual road for WOT in gears 3 and 4.... Chickend out just before the end of 3rd and also realised I was in drive and not sport!! Accelleration is earth shattering compared to pre dci.
I then went for a 60 mile mixed drive around the a406 and other B roads with the fuel guage hijacked to show IAT. Temps ranged between 70 and 90 degrees despite some hard ragging it and heavy traffic in places. Have to say that the car is an absolute beast now and continuously accellerates to red line in all gears (well I didn't max out in 5th or 6th but can say it pulled strong in each 5th ). I can't stress enough how much difference the dci has made right throughout the rev range and I now realise that the car was feeling breathless up top previously. Overtaking doesn't happen as a build up of speed, it just happens. Turbo spool up is very quick indeed.
All in all i'm happy to stop and leave everything as is for now as the car feels as complete as I could hope for it to be. Going out for another spin