308 cc Big Bore Kit
#14
This is an interesting option for owners of the 250 EFI models. The stock injectors and mapping seem to work up to around 315cc. After that, from investigations on the various forums, the bigger kits, such as BB or KK open up a can of tuning worms and expenses for EFI owners.
#15
Have faith Graham, I have spoken to 2 of the API's technicians & the ex senior programmer @ API Bangkok & they assure me the stock injector will work with their unlimited programmable box!! They say it's only the basic piggy-back systems that struggle to get full flow out of the injector.....They have got a 351 running strongly but haven't put the film on youtube yet. It's just a matter of time until someone that speaks English gets their big bore running well with a API box. The investigations on the various forums over the last couple of years have only been Juicebox & PC v piggy-back systems!!
“I have come across a programmable ECU from a Thai distributer, manufactured by API. In your opinion would this solve the BB flow issues?”
No. A reprogrammed ECU is only extending the injector pulse width, just like our EJK kit. The problem is the stock injector itself can’t flow any more fuel. Which you will only see if you go to the 330 BB kit.
I have another guy in the Carribian, Paul from Cycle care racing that has success with the 330 kit on EFI. This is what he had to say...
We used a Dynojet Powercommander PCV with the stock injector . We used a Web Cam with longer duration . We fitted a FMF exhaust . Opened the airbox . Used a de-restricted , aftermarket ECU to remove the speed limiter . Tuned it on a Land and Sea Dynomometer with load control and AFR sensor . After mods it ran well . It seemed a little rough in the transition from idle to 1\8 throttle . Otherwise it pulls hard in all gears .
Most of my tricky trails as well as city riding is in the 1/8 throttle. A little rough is not what I need after spending a chunk of change.
#16
No. A reprogrammed ECU is only extending the injector pulse width, just like our EJK kit. It seemed a little rough in the transition from idle to 1\8 throttle . Otherwise it pulls hard in all gears .
A little rough is not what I need after spending a chunk of change.
I'm not sure if your tech guy is familiar with the API programmable ecu, as he says it only controls pulse width. Now i'm not a technician or a spokesman for API but the programmable unit seems to control pulse width, frequency, flow rate & injection acceleration amongst a whole host of other things. He refers to it as a reprogrammed ecu, which it is not.
PM me your email address & i'll send you the api software (around 6 megs in size), install it & have a look at what it does & controls.
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jhoffy22
KLX 250S
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06-18-2011 12:17 AM