Required Upgrades for E-85?

[WildHorse]

In one case, it mostly worked but disabled knock advance. I wound up making it work by transplanting all the tuning data from the imrc-open mapped points to the equivalent-locationed imrc-closed mapped points, which worked in all aspects.

I guess that's what most tuning companies do. I have IMRC delete and the KS are definitely adding timing.

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[cbrtrx]

Yes raising the fuel pump voltage under demand I've been doing since the gen 1 cars, it's something to just squeeze a little bit more from the fuel system if needed. I've never seen any issues from doing so.

Gen 2 cars doing imrc delete leaves for some very small drive ability quirks that 99 percent of people would never know or feel unless you really take the time to dial it in. On a gen 3 car you don't notice any of the issues at all with them deleted. That being said I don't know why everyone wants to delete them so badly on a gen 3 car. I've personally haven't seen them fail on a gen 3 yet and I have tuned with them active at over 1200 rwhp for quite some time now.


There's so many ways to get to the same desired result, it's interesting the different paths we all take to get there though.

 

[Pistol_91]

But the 1000000 question. You ever figure out the proper tune for IMRC delete ?

I'm pretty sure it's been figured out for awhile now. There's 2 methods I've seen most. The lazy way, disable IMRC closed MPs and redo a few distance tables for the IMRC open MPs or, the better way, narrow it down to a few MPs and re calibrate everything to your liking. Either way works though...

 

[Pistol_91]

Something I forgot to mention earlier that I've yet to see a commercial tuner do is to vary the system voltage as a function of fuel flow. You can safely raise system voltage to 15.2 volts at only high fuel flows, which acts as a pseudo-bap if you don't have one, and can get more voltage from a bap if you do.

Mike, on my set up, e85 is too much for my fuel system. I will try this method and see how lift pressure holds since it was dropping quite a lot near 7k rpms. I will get back with results maybe next week.

 

[Angrey]

Mike, on my set up, e85 is too much for my fuel system. I will try this method and see how lift pressure holds since it was dropping quite a lot near 7k rpms. I will get back with results maybe next week.

There are some pretty sophisticated voltage boosters nowadays. I think the industry keeps old opinions of the days when it was a single on/off constant boost.

I was looking at the JMS unit which can be tethered to all sorts of inputs/controls (like APPS) when I was evaluating extending my dual pump output.

I'm currently right on the edge of both injector and fuel pump(s) and ended up going with the DW unit (which I haven't installed yet) because we can control the pumps through PWM so constant 18V seemed the best route with external control.

But for any advanced tuning, there's no need to run "hot" all the time everywhere. In fact, as long as it's kept cool and ventilated, I'm not sure the boosters now are any more of a failure risk/threat than the pumps themselves.

Tuners get nervous relying on a booster device at the most taxing engine conditions, but how is that any different than relying on the pumps not to take a shit?

In extended discussions with DW, they rate their pumps for intermittent and constant and most modern pumps (even the trashy ass brush style) can handle intermittent boosting without issue.

If you can't get there with the FPDM and upping voltage, I'd consider a variable booster that just adds in on the top end.

 

[engineermike]

Mike, on my set up, e85 is too much for my fuel system. I will try this method and see how lift pressure holds since it was dropping quite a lot near 7k rpms. I will get back with results maybe next week.

There’s a max fuel pump voltage setting at 12.5v that needs to be raised to 15.2 as well. Log system voltage and fpdm output duty cycle to confirm 15.2 and 49% to confirm it’s working.

 

[Pistol_91]

There are some pretty sophisticated voltage boosters nowadays. I think the industry keeps old opinions of the days when it was a single on/off constant boost.

I was looking at the JMS unit which can be tethered to all sorts of inputs/controls (like APPS) when I was evaluating extending my dual pump output.

I'm currently right on the edge of both injector and fuel pump(s) and ended up going with the DW unit (which I haven't installed yet) because we can control the pumps through PWM so constant 18V seemed the best route with external control.

But for any advanced tuning, there's no need to run "hot" all the time everywhere. In fact, as long as it's kept cool and ventilated, I'm not sure the boosters now are any more of a failure risk/threat than the pumps themselves.

Tuners get nervous relying on a booster device at the most taxing engine conditions, but how is that any different than relying on the pumps not to take a shit?

In extended discussions with DW, they rate their pumps for intermittent and constant and most modern pumps (even the trashy ass brush style) can handle intermittent boosting without issue.

If you can't get there with the FPDM and upping voltage, I'd consider a variable booster that just adds in on the top end.

I agree... I currently have the JMS bap and I like it alot. Easy install easy set up.

 

[LOL WUT]

@engineermike I wish I had someone local with your knowledge and willingness to step outside the “norm” of tuning these cars. Always love reading what you’re working on to optimize the tuning aspects of these cars.

 

[cbrtrx]

Mike, on my set up, e85 is too much for my fuel system. I will try this method and see how lift pressure holds since it was dropping quite a lot near 7k rpms. I will get back with results maybe next week.

You have a gen 3 car with stock fuel rails?

 

[Pistol_91]

You have a gen 3 car with stock fuel rails?

Yes sir

 

[engineermike]

But for any advanced tuning, there's no need to run "hot" all the time everywhere. In fact, as long as it's kept cool and ventilated, I'm not sure the boosters now are any more of a failure risk/threat than the pumps themselves.

Tuners get nervous relying on a booster device at the most taxing engine conditions, but how is that any different than relying on the pumps not to take a shit?

I agree. I worry more about one out of two (or three) pumps/relays/wiring failing and not knowing it until it's too late. If a BAP or single pump fails, more often than not you'll know about it before you go WOT. That's why I'm such a proponent of single pumps.

Another thing....my electrical and controls buddy pointed out that the variable output BAPs are cranking voltage up to 18-22 volts, then most certainly using PWM to lower it back down when in low voltage mode. PWM is the exact method the OEM FPDM uses to lower the voltage as well. So, if the FPDM has the capability to lower the voltage, then why not let the BAP run 22 all the time and let the stock FPDM pull it down to 12 when not needed. I'm sure I can program it to allow the FPDM to do that.

That said, if you run an FPDM and BAP, the tune needs to be changed to allow more than 12 or 12.5v to the fuel pump. Otherwise it will cut down the BAP output to some lower voltage around 15 and you don't get the full 18v.

 

[LOL WUT]

I agree. I worry more about one out of two (or three) pumps/relays/wiring failing and not knowing it until it's too late. If a BAP or single pump fails, more often than not you'll know about it before you go WOT. That's why I'm such a proponent of single pumps.

Another thing....my electrical and controls buddy pointed out that the variable output BAPs are cranking voltage up to 18-22 volts, then most certainly using PWM to lower it back down when in low voltage mode. PWM is the exact method the OEM FPDM uses to lower the voltage as well. So, if the FPDM has the capability to lower the voltage, then why not let the BAP run 22 all the time and let the stock FPDM pull it down to 12 when not needed. I'm sure I can program it to allow the FPDM to do that.

That said, if you run an FPDM and BAP, the tune needs to be changed to allow more than 12 or 12.5v to the fuel pump. Otherwise it will cut down the BAP output to some lower voltage around 15 and you don't get the full 18v.

If I were to convert my TI 274s into a single pump setup that I can drop into my radium bucket, is there a pump that’s more than up to the task of 1000rwhp and also a turn key solution? Essentially, remove 274s, drop in pump XYZ and send it.

 

[cbrtrx]

Yes sir

On gen 3 the stock rails are fairly restrictive. If you're dropping pressure fast above 7k I'd change the rails.

What is your setup now?

 

[Angrey]

I agree. I worry more about one out of two (or three) pumps/relays/wiring failing and not knowing it until it's too late. If a BAP or single pump fails, more often than not you'll know about it before you go WOT. That's why I'm such a proponent of single pumps.

Another thing....my electrical and controls buddy pointed out that the variable output BAPs are cranking voltage up to 18-22 volts, then most certainly using PWM to lower it back down when in low voltage mode. PWM is the exact method the OEM FPDM uses to lower the voltage as well. So, if the FPDM has the capability to lower the voltage, then why not let the BAP run 22 all the time and let the stock FPDM pull it down to 12 when not needed. I'm sure I can program it to allow the FPDM to do that.

That said, if you run an FPDM and BAP, the tune needs to be changed to allow more than 12 or 12.5v to the fuel pump. Otherwise it will cut down the BAP output to some lower voltage around 15 and you don't get the full 18v.

I was always under the impression that the PWM managed pulse width and duration so constant voltage, just varying intermittent current. So instead of a DC current, you get almost a multi-phase current based off how wide the pulses are. I suppose it could also vary the height (voltage of the pulse). In order to vary voltage, it would need much larger infrastructure (with heat sink/fins for venting) no?

 

[Pistol_91]

On gen 3 the stock rails are fairly restrictive. If you're dropping pressure fast above 7k I'd change the rails.

What is your setup now?

I have lift pump pressure drop not rail pressure drop. Ess 120mm 93

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