Mike O.

So far, I have tried three Wett K04 chips, the Wett K03 chip and the stock chip and K04V4 is still the best. It is the one I used for data logging in an earlier post.

I went down to the stock 4bar FPR when I put the 312cc Bosch injectors in. Funny thing - my stock injectors flowed at 240-241cc when tested.

Part throttle 02 readings are well in the .800s which is really nice. The car feels a lot better at part throttle. Came home after a 15 minute part throttle run and the turbo was completely dark. This was never the case with the old injectors.

Naturally, the car falls flat on its face at WOT. I am getting about 29% more fuel per pulse with these injectors which is way too fat.

I am going to ask Wett to reprogram the K04 chip to start. I am thinking about dropping back 5% on the part throttle injector timing to start. WOT needs the a little more tweaking. My math says that to get the same fuel as the old injectors gave at 16.32, I need to ask for 12.60ms. To get this I used 16.32ms * 241cc = 312cc * 12.60ms

Because the old setup was slightly lean (O.K. it was a lot lean) I want to add 5% and 10% extra timing on two different chips. It shouldn't be too hard to write two different WOT maps. My calcs show that 13.23ms should yield 5% more fuel and 13.86ms should yield 10% more fuel.

I hope to have some stuff later this week (or it will be off to GIAC for custom programming).

Let me know your thoughts,
Mike O.

CMH

He already told me that he would do a friends car with this setup.

jsa4

Trying to contact Garrett, can someone provide phone #

Jenner

1.714.368.0145

xr4tic

Since the injector open/close time is probably the same for both size injectors, it should be factored in, depending on what it is.

Example:
If the open/close times are .5ms ea (just guessing), then actual injector full open time is 15.32, multiply that by 241/312, and you get 11.83, then add back in the open/close times to get 12.83 (compared to 12.6)

I would assume that whatever chip tuner you use would know these times (and if they do, it wouldn't hurt to ask what they are, I'd like to know) and could compensate for it. In other words, don't go asking for 12.6ms injector times or you may be worse off...

Also, what are the stock injectors supposed to be if yours flowed 240?

Thanks,

Kevin K2

the oem 240 cc injectors are rated at 4 bar, as I recall. most injectors are rated at 3 bar .... verify the test pressure for the 312's. If 3 bar they will flow 15% more at 4 bar ... like 361 cc/min.