Can you tune around the pprv?

[Emmanueldsg]

Is it possible to tune around the pprv so it doesn’t bog instead of deleting it or getting a return fuel system


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[01yellercobra]

Yes.

 

[Black02GT]

Is it possible to tune around the pprv so it doesn’t bog instead of deleting it or getting a return fuel system


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Yes and No. Tuning around the PPRV is tougher and kinda of a waste of effort IMHO. Tuning the returnless system PIDs right to keep returnless and not pop your FRPS isn't bad (everything else in place but ditch the check valve). I think the guy (so sorry I forget the name c6/c5hombre) has @04sleeper car/tune made it work at 700+ and e85. Still not the easiest and has both pros and cons.

 

[SecondhandSnake]

I think you could, but it's more of a band aid solution and I'd be concerned with it being consistent across the board. Personally I'd delete it if you see an issue.

The issue is with the valve closing during shifts, cutting flow and pressure. You could compensate by increasing the transient fueling via manifold volume. The hard part would be balancing it so that you don't bog, especially during slow shifts or part throttle.

For the PIDs I don't know how much they would help. I didn't even mess with them with the PPRV deleted and it ran great in the 600ish level on gasoline.

 

[HuntFishCobra]

I have a link saved somewhere that shows the specific way to do it. Just gotta find it... but yes a good tune should be perfectly fine and not a band aid fix as some say IMO

 

[01yellercobra]

I think you could, but it's more of a band aid solution and I'd be concerned with it being consistent across the board. Personally I'd delete it if you see an issue.

The issue is with the valve closing during shifts, cutting flow and pressure. You could compensate by increasing the transient fueling via manifold volume. The hard part would be balancing it so that you don't bog, especially during slow shifts or part throttle.

For the PIDs I don't know how much they would help. I didn't even mess with them with the PPRV deleted and it ran great in the 600ish level on gasoline.

The issue really isn't the PPRV. Yes, it can be a restriction, but the issue is the ECU controlling the pumps. When you're on it at WOT the ECU has the pumps at 100%. You lift to shift and the pressure spikes so the ECU slows the pumps down. You get back on it and now the ECU has to tell the pumps to spin back up to catch up. If you shift fast enough the pressure doesn't drop too much.

Adjusting the PIDs delays the ECU's response a little. It doesn't slow down the pumps as fast so the pressure doesn't fall off as quick.

 

[HuntFishCobra]

Was it scaling the map so it doesn’t peg itself?

The issue really isn't the PPRV. Yes, it can be a restriction, but the issue is the ECU controlling the pumps. When you're on it at WOT the ECU has the pumps at 100%. You lift to shift and the pressure spikes so the ECU slows the pumps down. You get back on it and now the ECU has to tell the pumps to spin back up to catch up. If you shift fast enough the pressure doesn't drop too much.

Adjusting the PIDs delays the ECU's response a little. It doesn't slow down the pumps as fast so the pressure doesn't fall off as quick.

 

[BlckBox04]

I would just delete it. It’s not worth the extra effort.

 

[01yellercobra]

Was it scaling the map so it doesn’t peg itself?

No. Its actually going in and changing values. Nothing is scaled. There's also a value that is set so it doesn't read above a certain fuel pressure. I might have the whole thing saved, but it would be on another computer.

I would just delete it. It’s not worth the extra effort.

I'd rather open a laptop than drop a tank personally. But that could be because I hate dropping tanks.

 

[HuntFishCobra]

I have to go outside to grab my laptop to find that link I saved and it’s 9 degrees today so ima just wait on that one haha

 

[c6zhombre]

Is it possible to tune around the pprv so it doesn’t bog instead of deleting it or getting a return fuel system


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Yes it can be done. You might try contacting 04sleeper if you are interested in a professional tune. He'll probably recommend going full return as first choice....but if you are steadfast on remaining returnless he has tuned countless returnless cars to big power numbers, including mine. It has worked flawless for over a decade on E85 and 700+ power

 

[HuntFishCobra]

got my computer, try this
https://www.modularfords.com/threads/94535-Returnless-Fuel-System-Hesitation-Discussion?highlight=fly+wire

I have a link saved somewhere that shows the specific way to do it. Just gotta find it... but yes a good tune should be perfectly fine and not a band aid fix as some say IMO