I have the opportunity to have the JCW ECU software put in my car.

Is this worthwhile or no in my car's current state of tune? I will be buying an intake soon as well, though I don't really expect this to affect this question much.

I'm concerned about the JCW tuning expecting the increased fuel flow of the JCW injectors and running lean.

Anyone with any technical knowledge on the subject care to chime in on this one?

Thanks!!!

 

Don't do it, don't do it, don't do it. I'm not sure if it'll do damage or not (run lean) but one guy here did have a similar setup and he LOST tremendous power with the JCW software. The JCW software is very specific for their mods which include a different head (and a 13% pulley and larger injectors). Seriously, one of the MINIs they used for GIAC testing showed the JCW software lost over 10hp compared to stock and more than 20hp compared to the tuned GIAC. And this was for a 15% pulley.

So unless you want to negate the power gained by your pulley, don't do it. The stock software can handle your mods much better.

 

Interesting - it was billed to me as making cars with similar mods "way faster and smoother"

 

Just telling you what I was told. I've spoken to both Helix (who was present for the testing) AND the owner of the car (who was also present for the testing). Everyone was shocked to see his non-JCW modded S lose significant power.

 

Cool - thanks for the info!

 

I wonder why that is - do you need the injectors, etc to optimize it?

 

I wouldn't do it Mark. The JCW software is mapped/designed specifically for the hardware in the kit. Even if your mods are close to the JCW, they are not the same. I'm sure they spent quite a bit of time dialing in the software to work with what's in that kit.

 

if all that is the case the stock tuning is designed specifically to work with NO MODS ? how can it possibly adapt better ? At least the JCW is mapped for more boost and bigger injectors.

Maybe the car in question is just a freak, mini's tend to vary considerably from one car to the next so who knows. And I am not doubting what anyone saw just curious how stock can possibly adapt better when the jcw is programmed for more out of the boX??

 

My guess is that the stock ECU is not only adaptable but very generically tuned. Like it's tuned for 91-98 octane. But if you tune your ECU specifically for 93 or 100 octane, you wouldn't want to use 91.

I think the JCW tune is just a very specific tune that takes advantage of the head or something that an intake, exhaust and pulley car doesn't have. It's not like the JCW ECU upgrade didn't work. In fact he THOUGHT it was fast. But the dyno showed a peak power LOSS. There is also the possibility (and probability) that the JCW ECU is a detune for safety. With the extra boost and such maybe the JCW ecu detunes the stock software for added safety.

 

thats interesting. Maybe it has everything to do with lack of flow from not having the head done.

I see your points about the possibilities of the programing but if they did de tune it they would even get the #'s they do on a stock JCW car.

BTW I believe the jcw pulley is just short of 15% not 13%, slight difference but I thought I would toss that out anyway.

 

i have the jcw tuning with aftermarket mods (15% alta pulley etc.) my car is faster with smoother acceleration compared to the regular tuning.

 

do you have the head done ? I am actually getting th elatest version of the jcw software put on my car today.

 

What's the cost of the JCW flash?

 

I dont know what it would cost, the hard part is finding someone who will do it on a non JCW car.

 

no head, just pulley, plugs, wires, cai, and lower temperature thermostat. the milltek is next.

 

I will let you know what I think once its done. I also have the apexi so I have a little more tuneability to add to the jcw software.

 

I asked my dealer in the context of installing thew JCW upgrade myself and then brining them the car to flash the ECU. Quoted $49.50, but I wonder if they'll balk if its not for parts purchased from that dealership.

 

They will most likely balk at it if you don't have the injectors or the airbox. I got a free JCW DME flash when I had the injectors and airbox installed.

The dealer also knew that I had an aftermarket cylinder head. That came up during the deliberations.

 

While I have an aftermarket cylinder head, I have to agree with you. Better than regular tuning or some of the aftermarket chips I've tried. Smoother with better throttle response.

 

Not true ... the airbox has its own control unit which is wired into the ECU and opens the flap at 4500 rpm.

The JCW airbox can be fitted to a stock 'S' and no flash is required.

 

You are correct, the control box has a wire to the fusebox, ground wire, and an engine signal wire that goes into the CPU. When it revs over 4500rpm, it opens the vacuum valve.

 

I had mine flashed with v42.2 of the Jcw software and the car is running better than ever before. I dont know if its making more power or not but its smooth and linear throught the entire range. Definitly better than the standard software.

 

Ditto

 

greatgro! What's up?

Just one tiny correction; JCW pulley is 14.7%

 

must u guys keep doing these things to your cars i mean come when is enough enough
but on the bright side more things for me to kix when u break them