Boosted injector ratio - Toyota GR86, 86, FR-S and Subaru BRZ Forum & Owners Community

504 · 11-01-2019, 05:59 PM

Hi folks,

coming up on my final ecutek tune revision hopefully. My tuner has the injector ratio raised on high loads upto 70% port as seen in the attachment. Question is, is this necessary for say 260kw on e85, 12psi? or 240kw 98.

How much can the DI take before running out of puff?? and I presume we want to maximise the use of DI for the purposes of knock reduction

my port injectors are deatchwerks 700cc

tomm.brz · 11-01-2019, 06:54 PM

Usually safe limit of DI is an opening time of just under 6ms, so that with colder weather it doesn't go over 6.5ms
But better stay at 6ms when cold

And more than 2ms from end of injection and spark

Modify accordingly to this

DBW · 11-01-2019, 07:48 PM

I think your tuner has it backwards... 700cc injectors should be no where near that for your power level. With that PI/DI injection ratio your DI injectors would be around 2ms at redline.

504 · 11-02-2019, 03:53 AM

I've got no way to measure ms unfortunately, this is really good information though

Would I be safe running 50% on high load? and what do you estimate ms to be?

thanks guys

tomm.brz · 11-02-2019, 04:50 AM

Well, start at looking at the opening and increase DI to reach 5.5 ms maximum and you should be good

11-01-2019, 05:59 PM	#1
504 Senior Member Join Date: Feb 2013 Drives: 2014 86 GTS Location: Sydney, Australia Posts: 168 Thanks: 131 Thanked 85 Times in 57 Posts Mentioned: 4 Post(s)	Boosted injector ratio Hi folks, coming up on my final ecutek tune revision hopefully. My tuner has the injector ratio raised on high loads upto 70% port as seen in the attachment. Question is, is this necessary for say 260kw on e85, 12psi? or 240kw 98. How much can the DI take before running out of puff?? and I presume we want to maximise the use of DI for the purposes of knock reduction my port injectors are deatchwerks 700cc Attached Images

11-01-2019, 07:48 PM	#3
DBW Motorsports Join Date: Nov 2011 Drives: 19BRZ PP, 16 M4 Location: ATLANTA, GA Posts: 67 Thanks: 36 Thanked 62 Times in 27 Posts Mentioned: 16 Post(s)	I think your tuner has it backwards... 700cc injectors should be no where near that for your power level. With that PI/DI injection ratio your DI injectors would be around 2ms at redline. __________________ Douglas W.

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11-01-2019, 06:54 PM	#2
tomm.brz Senior Member Join Date: Jan 2017 Drives: brz 2017 hksv2 Location: italy Posts: 2,292 Thanks: 517 Thanked 1,125 Times in 815 Posts Mentioned: 70 Post(s)	Usually safe limit of DI is an opening time of just under 6ms, so that with colder weather it doesn't go over 6.5ms But better stay at 6ms when cold And more than 2ms from end of injection and spark Modify accordingly to this

11-02-2019, 03:53 AM	#4
504 Senior Member Join Date: Feb 2013 Drives: 2014 86 GTS Location: Sydney, Australia Posts: 168 Thanks: 131 Thanked 85 Times in 57 Posts Mentioned: 4 Post(s)	I've got no way to measure ms unfortunately, this is really good information though Would I be safe running 50% on high load? and what do you estimate ms to be? thanks guys

11-02-2019, 04:50 AM	#5
tomm.brz Senior Member Join Date: Jan 2017 Drives: brz 2017 hksv2 Location: italy Posts: 2,292 Thanks: 517 Thanked 1,125 Times in 815 Posts Mentioned: 70 Post(s)	Well, start at looking at the opening and increase DI to reach 5.5 ms maximum and you should be good

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