that was awesome but you couldn't use it to do a engine swap. We need a proper 4 post lift

 

I'd rather take it to a shop...

 

Yes & no. Without fuel pressure compensation against boost pressure the actual injector flow rate decreases with boost. At least I'm not aware that you have compensated fuel pressure correction (most Renesis turbos don't) so that might be a fail for me.


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I am running the BHR pump, that is it for fuel upgrades. It just goes rich as fawk. When I look at all the tables everything looks good to me but I am still a newb.

 

Wouldn't that require going to a return style fuel system with 1:1 rising rate regulator?

 

Remember the fuel VE table.... we talked about this.

 

Talk to me brother, refresh my memory! I know we made small changes and I continued to make very small changes but it doesn't seem to have made a difference. Let me look.

 

For boost vs fuel pressure in a return-less system, we increase the VE table at higher loads to create a "virtual" rising rate regulator. Ringing any bells?

 

it's going rich for other reasons as noted. Just pointing out that atmospheric measurement of fuel injector flow rate decreases with boost pressure without fuel pressure compensation. So as a made up example; 600 cc/min atmospheric might be 400 cc/min or less at 14 psi boost without fuel pressure compensation. It would be the same approx. flow as having 14 psig less fuel pressure because boost pressure is working against fuel pressure as it is being injected. Yes, it takes modifications to the OE system as mentioned, but then also doesn't require as much injector sizing either for a given power output. Just something many people have overlooked when sizing injectors for this application

 

Dude just start over with the base tune, idle logs, cruise logs, boost, timing.

Don't guess and go with what feels good, gotta be scientific on dat ***.

You can unfuck this whole deal by starting over.

 

Side note, since Scott is using blues wouldn't his injector latency need to be adjusted since the latency in the base tune is for yellows? Or does that not change between the two.

 

Not really a big deal as the latency difference between yellow and blues is fairly insignificant. However this is why aftermarket injectors mixed with OEM causes so many issues for a lot of people.

 

Drat! I thought I had something there...

 

Since we're talking about injector latency I have a quick question.

How is injector latency affected by upgrading/uncapping the stock injectors?

I'll be sending out the stock yellow P2's to KG Parts and was curious about the possible latency difference because the latency for the P2's and Secondaries can only be adjusted together on the same table.

Will the Latency tables require any changes?

Edit: Since Injector Latency is the time it takes for the Injector to open that's something that shouldn't change when KG Parts upgrades them correct?

 

Yeah I am just starting over.

 

The latency will change with the modified injectors.....how much is the issue It also changes with fuel pressure, Baro, voltage etc

 

It has puzzled me for a long time that the uncapped yellows don't flow what they should . latency should be more to do with the actual mechanism and nothing to do with the tip design but the results suggest otherwise.

 

Ever see the spray pattern from the uncapped injectors? If you did you would buck up for some bigger ones that haven't had the discs removed.....

 

I know it changes with fuel pressure, voltage and barometric pressure, but isn't that taken into account in the latency tables, I know with other Ecu's and applications it is. I'm on my phone so I can't look right now and haven't really done much with tuning just starting to do some research now.

Now the question is, since the P2's and Secondaries will have different latency's does the table have to be changed at all because they can't be adjusted independently?

 

Why would the latency change? The actuator is the same voltage and resistance. All you are doing is allowing more fuel to come out. The internals stay the same its not regulated by the cap. When switching to id or an rc injector or possibly to s2 injectors you'd need to change it due to different resistance on the actuator.

It adjusts according to the baro and battery voltage, but the adjustments are a calculation using the latency that we input. It won't recalculate the latency it just uses it as a reference.

Thats how I understood it at least... but I have adhd so I get confused allot.

 

That's what I was thinking Shady

 

The latency will change with the altered flow. It will also change the closing time as well. I doubt it is a really significant value..but it will be different

 

The latency is just how quickly the actuator opens correct?

If that is the case removing the caps would not effect it at all. The only reason you would need to adjust this is if the actuator was getting old and damaged and no longer operating at the specified resistance.

I just read a little bit and found some more info. The values can be effected by manifold pressure and fuel pressure.

So that would explain why the boosted guys would need to look at this table.

 

Injector Dynamics - Drillbits and Dipshits

Have a look at this...and then read a couple of the other fuel injectors articles on this site and it will likely make things clearer

 

Thanks for the link, good stuff. I put the injector bank 2 values back to where I had them a few tunes ago and upped the bank 3 to 700 and the car is driving well again. Not perfect, still some rich spots under certain conditions but not 10.0 and misfiring rich. This will do until I get time to log an retune this weekend.

Did a quick pull to 7,000RPM or so. Oops,

http://www.flickr.com/photos/9krpmrx8/8162325122/