Zax Bugeye "Shaggin' wagon" Build thread by zax | subaru | builds

Home
Subaru
Impreza Gen2
Builds
Zax Bugeye "Shaggin' wagon" Build thread by zax

By diyauto

( 2 )

3 minute(s) of a 100 minute read

2-19-2014

2-19-2014

Just a word of warning to those who stumble upon this thread:

After installing the ID1000s, I was a bit curious that the LTFTs were consistently 8-10%. This was also reflected in the OL fueling. Since I reverted back to the stock airbox to scale my injectors, latency, and TIE, I thought it was unlikely that my stock MAFv scaling could be that far off. However, after some research, this is what I've found.

The industry standard for testing injectors is using the fluid n-Heptane. When installed in your car, the injectors flow gasoline. The viscosity of n-Heptane is 0.684 g/cc vs. the 0.75 g/cc viscosity of gasoline. As such, n-Heptane flows 0.91x that of gasoline. The value in Rom-Raider is compared to the stock injectors and the stock injector's flow rate is calculated using n-Heptane. InjectorDynamics uses gasoline for flow testing. There is nothing wrong with this method -- in fact I prefer that ID uses the intended medium for flow testing. However, this means that the flow rate defined in RR should be 0.91 * the advertised flow rate of 1015cc/min. In RR, you shoud enter the injector flow rate of approx. 925cc/min.

Tuning the TIE has been a bit of a journey. The tough part is adjusting all the comps IMO. The boost-error compensation does not make much sense to me on the MBC, but zeroing the tables doesn't seem to help the overall TIE. Perhaps it's because I'd have to adjust the throttle TIE after zeroing out the comps.

Here is my main point of frustration: since the Injectors are 220% larger than stock, the added IPW for the TIE is very short at the low throttle angles. This makes capturing the event much more difficult and I find myself bumping into logging resolution.

For the most part, the starting TIE map is set to 45% of the stock additional IPW with an additional 20% of IPW for other modifications. This is 54% of the stock additional IPW.