Quote:
Originally Posted by Joshinator99
Good stuff Travis. I’ve modified the VBat table since I noticed it reduces the duty cycle at “normal” car voltages, so I put that table to 1.00 to stop that. I also put allowed max DC to 130, expecting that to help but it didn’t. Seemed to get worse actually.
|
It's a balancing act. Too high or too low and the fuel supply will not be optimal. When you max out settings, one of two things will happen. Either the pump will start cavitating and reduce flow or you'll bump up against a max pressure which will trigger a large correction.
I've learned you have to try to keep it right in the sweet spot at WOT (~500 KPA). Not higher or lower. Of course, you'll get some minor correction during shifts, but with steady demand the pressure should be really steady. If not, something is not optimal.
If I may offer more advice, I'd say do your best to configure the tables as close to the actual performance of the pump as possible. Find every spec sheet or test you can find to get actual numbers. When everything is in balance, I'm confident that's when the pump will provide the most fuel. Don't be tempted to bump up settings in an attempt to make the pump work harder. That's what I was doing, and I wasted days of my life tweaking settings only to find out that's not how it works best. It's like whac-a-mole. A tweak in one place may appear to make things better under a specific condition, but somewhere else a problem will crop up.
After tweaking pretty much everything, I landed on a config with only the High Flow mode conditions slightly tweaked to be enabled at 3,200. Everything else is now back to stock with the fuel pump tune (just using the JMS booster now). (I know your pump is different than mine, but just sharing my experience.)
Quote:
Originally Posted by Joshinator99
...
I guess another possibility is the factory fuel line might not be big enough?
|
The factory fuel line should be plenty large enough. Going to a larger line might improve the pressure drops by a few PSI, but I don't think it will make a meaningful difference.
Quote:
Originally Posted by Joshinator99
...
I’m running the LPE check and eliminated the tiny OEM one that was pinched into the original fuel hose, so hopefully that is one bottleneck gone. But I found it interesting that I was holding full 2900# rail pressure even though the low side was dropping pretty good, so I’m thinking maybe the check setup helped with that.
|
That's interesting! My check valve is stock and the pressure drops seemed to correlate pretty well between the low and high side. Who knows? Maybe it does make a positive difference.