Depends on the dealer..(some dealers say no unless it is a JCW, some say, ok, your car, here is the programming fee ((about an hour, keep quiet) and the year car (computer revision number). The 05'+ got a new computer, that was updated a bit, and while related, is still a bit differant that the older cars (the computer can be fitted to older cars).
One local guy, and club member here tried to get his car a JCW flash, and was told that his model year was mosly fuel injector scaling/timing advance, but the jcw flash was a bit more indepth on the 05+....they gave him a ream of papers...listing issues.....He did have a signafigant number of JCW parts....
In the end he did not do it...but a bit of research will show you very few non-jcw drivers are happy with JCW flashes...they just run too rich for cars making less than 200-210 hp....the jcw afterall does have a mildly ported head...the stock does not, and subsquently does not flow quite as well, resulting in richer than optimum operation.

 

Thanks Jack, that European Car Mini Project was a good read. I am surprised how long it took them to figure out that they needed a tune and colder plugs. LOL

They went from 155hp to 191hp with an exhaust, CAI, 15% pulley, colder plugs and a dyno tune. That's a 23% increase in power. Not too shabby.

I am surprised that they were running too rich at the top end, considering they never mentioned larger injectors. I would have thought they would run lean.

 

Tom2112,

It's a common practice by many manufacturers to err on the side of caution and dump extra fuel at WOT with boostfed engines. It's a loss of gas, and a slight loss in power, but it guarantees the engine won't run lean, which leads to extra heat and detonation. You NEVER want detonation in a boostfed engine; it's almost guaranteed destruction.

 

I've run 440's and 550's, currently running the 550's with the Mynes tune and got 220whp on the Mustang dyno and the car runs smooth as silk right to 7.5k rpm.

 

I will say, combined with a really high RPM range, a larger injector might be required. A 15% pulley, CAI, and tune easily changes the peak HP from 6,000 RPM to 7,000 RPM. How much more you would need beyond that I would not know without talking with some of the shop techs here.

 

What JumoingJackFlash just said is why a lot of sport bike run staged (two sets) of injectors. 1 set runs at idle and low rpm/load, the other set comes in at high load high RPM to meet fuel demands. If you were to try to do it with just one set your injectors would be so big that you wouldnt be able to control them properly at idle unless you were willing to sacrifice some precision.

 

Thanks. I knew someone would chime in and elaborate.

 

remember this is gross HP. If you're running a SC, a lot of HP goes into spinning the sucker at max load and RPM. Figure 10%-30% or so increase over crank HP is what the engine is really doing. It takes a lot of power to compress a high volume of air....

Matt

 

Did you get the same tune as me

 

Just to clarify, when I said the second set come in mean they start running along side the primaries, so you basically have 8 injectors going at once. That was kinda unclear in my above post.

Having two sets though can be interesting depending on where you place them, too far up the intake and you have to start designing it to both direct the air properly and keep the fuel in suspension, not an easy thing to optimize.

 

Does anyone have the numbers on the amount of hp our supercharger uses to spin at certain RPM?

 

digging around the Eaton site. There are also some books that will give you an approximation based on the volume of air and the boost you're running. I'd guess that it's taking about 30 HP on an ~200 HP car, but that's just a guess....

Matt

 

I have heard some top fuel setups waste 700 HP to spin their superchargers. But, don't forget they are making 7,000-8,000 HP these days.

 

Yes, just said 'gimme what he's got'

 

are their any issues with fuel pressure when running the 550 injectors with only basic mods (intake, pulley, exhaust)?

 

What counts is having the fuel flow provided you need it. Even with larger injectors, the computer should continue to work toward maintaining 14.7:1 air/fuel ratio. Only in WOT mode (>80% throttle) will this change. Not sure how much the computer will give the engine in WOT mode if you have them installed. I would definitely consult a tuner.

 

When it hits open loop mode (WOT) you will probably go rich, which for a boosted engine isnt really that big a deal at all.

I dont know how adaptive our ECU really is. If it is like the ones I work on though it probably samples AFRs at steady state conditions (stable throttle and RPM) and updates map points to target AFRs. BMW probably only limits that change to a few percent from base though for safety reasons. If you go through an unupdated map point in open loop mode it will open the injector for as long as if it were stock. Thus with 550cc you will get more fuel without having touched the ECU. Again rich AFRs on a boosted engine (11-12.3 to 1) are definitely where you want to be when you consider what going lean does... Then you just have to make sure you arent getting to much gas into your motor oil.

You raised the issue of fuel pressure. The only way to know for sure would be to hook up a gauge to the fuel rail and watch what it does on the stockers and on the 550s. If you pressure starts to drop you do risk leaning out (at least in open loop mode). On the other hand you are also running bigger injectors so you dont need as much pressure to flow the same as a smaller one. If you really wnated to know how much pressure loss you could take you could plot some injectors on a graph of pressure vs. Flow and see where they intersect with the stock ones.