ZR-1 Net Registry Forums  

Go Back   ZR-1 Net Registry Forums > C4 ZR-1 > C4 ZR-1 Technical Postings

Reply
 
Thread Tools Display Modes
Old 02-02-2014   #1
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,697
Default Tuning for NOT Gasoline

Some time ago I believe Halverson brought up the subject of tuning for E85 and the LT-5. That's been something done for the LS-7 so understandable Hib would bring it up here. Of course, newer Powertrain management systems are automatically adapting to various fuels thru flex fuel systems. For many of us
E10 is the primary fuel available so I thought I'd would just reiterate a point when dealing w any fuel other than straight gas.

Forget AFR for a moment and think in terms of Lambda. Lambda is "agnostic" to the type of fuel being used. A Lambda of 1 is always stoich for that fuel. If you are burning E10, a Lambda of 1 occurs at an AFR of less than 14.7 for a WB calibrated to E0. By telling the ECM you are shooting for an AFR of 14.3, the ECM uses that as part of its PW calc, automatically making the mixture richer in respect to a 14.7 stoich, but correct for a 14.3 stoich.
Now I understand that when I see a Lambda of 1 on my ZT-2, it's saying that I am at 14.3(the AFR commanded in my cal) although my AFR gauge reads 14.7.


That's why just setting the Stoich AFR does the trick because the NBO2 switching point will be for whatever fuel basically. And since AFR adjusts the PW, more fuel will be added(if lowering the AFR) correspondingly to hit 128 if you are tuning for C/L. Tuning for E85 then would follow in the same way. So for WOT tuning, unless your WB can be re calibrated for the fuel being used, the indicated AFR would need to be corrected. As an example, if I tune WOT to an indicated 13:1AFR
straight gas, I should really be down around an indicated 12.6:1 for E10 IF I am using UNCORRECTED AFR to tune. 13/14.7= .884, then 14.3*.884= 12.6 indicated.

This is where a bin switcher becomes helpful for us. You could have multiple cals loaded using various AFR constants depending on the fuel being used. You would do that manually. Incorporating a flex fuel sensor would be cool to then automatically invoke the appropriate calibration.
__________________
[SIGPIC][/SIGPIC]Former Membership Chairman
Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX

Last edited by XfireZ51; 02-02-2014 at 11:22 AM.
XfireZ51 is offline   Reply With Quote
Old 02-02-2014   #2
mike100
 
Join Date: Feb 2011
Location: San Marcos CA
Posts: 1,802
Default Re: Tuning for NOT Gasoline

Has anybody done any good dyno testing of what the difference with a pure gasoline tune puts out vs an adjusted E10 calibration? I thought about using a BIN switcher once, but not sure i wanted to run the wires thru the ecm case.

btw,
not sure the regular tunerpro definition has the addressing for the target AFR, but I might like to play with that and the Inj offset now that I have an Ostrich and can make changes more easily.
mike100 is offline   Reply With Quote
Old 02-02-2014   #3
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,697
Default Re: Tuning for NOT Gasoline

Mike

Here's a good thread from ls1tech re:E85. My post dealt with just the tune. Other aspects involve the additional fuel required and delivering it.
http://m.ls1tech.com/forums/showthre...395&styleid=25
__________________
[SIGPIC][/SIGPIC]Former Membership Chairman
Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX
XfireZ51 is offline   Reply With Quote
Old 02-03-2014   #4
rkreigh
 
Join Date: Jan 2004
Location: Alex VA
Posts: 1,087
Default Re: Tuning for NOT Gasoline

I also was inquiring about E85 tuning hoping to tame the high HC (140+) and get down to the insane 48 HC needed to pass the roller tests here in VA

the Raptor solution might do that but I don't know if they have a flex fuel sensor which really does help.

I'm going flex fuel and e85 with a Haltech S2000 ecm on my TT z06 in the hopes of picking up a bit of HP and reliability

with E85, we could easily bump up the compression on the LT5 and gain some power

the fuel system would need to be upgraded with bigger pumps, e85 fuel lines, and bigger injectors

an expensive proposition time you go through the tuning!
__________________
95 390 LPE ZR1 (505 rwhp)
LSV = Lingenfelter Super Vette
Twin Turbo 2003 Z06 (800 RWHP)
rkreigh is offline   Reply With Quote
Old 02-03-2014   #5
RHanselman
 
RHanselman's Avatar
 
Join Date: Jul 2005
Location: Cresson, TX
Posts: 970
Default Re: Tuning for NOT Gasoline

Yes the Mega Squirt and Raptor development ECM will tune for flex fuel. You just need the sensor.

Of course the fuel system also needs to be modified for E85...
__________________
Ron Hanselman
Founding Member #80
CM Lifetime Member #1093

1991 #383 Twin Turbo
1993 #099 Ruby, Jeal 368 w/Snake Skinner body
1961 White with Red Int
RHanselman is offline   Reply With Quote
Old 02-04-2014   #6
rkreigh
 
Join Date: Jan 2004
Location: Alex VA
Posts: 1,087
Default Re: Tuning for NOT Gasoline

that is awesome.

when do you think it will be available and how much? love to hear more about the TT project

you KNOW how anxious I am.

I'll post up here my experiences with E85 and the Haltech on the Z06

looking to use that car as the "experiment" before I take the plunge and do E85 + TT on the ZR-1

I think E85 will help tremendously

also like to hear about the costs to run the "stretched liners" and mill a receiver groove in the heads. sounds like some precision machine work but the way to go to run the high cyl pressure and not blow HG

the AES liners might improve sealing with a good set of head studs too.

all it takes is money, and LOTS of it!
__________________
95 390 LPE ZR1 (505 rwhp)
LSV = Lingenfelter Super Vette
Twin Turbo 2003 Z06 (800 RWHP)
rkreigh is offline   Reply With Quote
Reply


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:30 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright ZR-1 Net Registry 2020