How to make sure flex spark adder table wont work below a given %

[twistedpixels]

I just got my car back and it was tuned on e85. I wont be running it on e85 all the time and I just put 100 in it and even at 20% ethanol it is still adding the full amount of additional spark from table #12678 in my E38 ECM for Z06. Also the tuner left the min ethanol percentage box at 0% and put max ethanol % at 100%. Delay and default percentage are both 0% and transition volume is at .12L. I remember there being some way to disable the spark adder table with e85 when below say 50% if you wanted to do that.

[G8NOOBIE]

have a tune file available?

[twistedpixels]

have a tune file available?

here ya go!

new motor original tune file.hpt

[G8NOOBIE]

i would set default % to say 11%, max ethanol to 80%transition to 0%. i havent figured out the timing part of your question but in my tune flex fuel spark is zero'd out and all the timing adjustments for e85 is in the PE alcohol adder. multi vs comp on mine goes from 0 .100 .400 .750 1.00 multi vs map is set the same as yours

[twistedpixels]

There has to be a way to keep the timing from being added when running normal pump with e10. 100 octane has no ethanol in it but right now it still has a little. I just dont want it adding more than it should. Otherwise I have to load in a different tune every time I change fuels which is not ideal. I am pretty sure I can run similar timing on 100 as e85 but if I ever get stuck and have to put 91 in it and dont have my laptop I want to be sure it wont add crazy timing if the ALky% is below 50%. That is pretty much the minimum I would say is safe still. Could be wrong.

[G8NOOBIE]

I’ll have to do some looking around to see if I can find a answer for your question. Someone much smarter than me hopefully chimes in

[G8NOOBIE]

im pretty sure its in the multi vs comp fueling tab. try setting 25% to .000 and 50% to .000 and 75% to .750 and see what happens and log it

[twistedpixels]

im pretty sure its in the multi vs comp fueling tab. try setting 25% to .000 and 50% to .000 and 75% to .750 and see what happens and log it

There are other issues with this tune like poor cold and hot starts. Tried increasing startup air and adjusting cranking fuel and spark up and down with no change. Car still hard starts and often fails on hot starts. The motor is new with almost 500 miles. We just pulled plugs and readjusted valves yesterday. everything looked good. I am running the same exhaust and a new stock starter as well. It barely wants to turn over once it heat soaks for a few minutes. I have to give it some gas to get it to fire up which is why I increased startup air. With 20% additional air it made no difference. My cranking VE is at 65 already and that was done by the tuner. Not sure if I should mess with it. Not thrilled about the maf only tune either. This is an expensive motor with pretty high compression at 12.4:1. Cam is not that big though.

[G8NOOBIE]

What’s your setup

[07GTS]

i would set default % to say 11%

i changed mine so default is 80% my thinking was if sensor fails and ur on petrol it just goes rich and on ethanol it stays safe, but if ur on ethanol and default is 11% if it fails its going to lean u out and that could be bad

[07GTS]

if u have scaled your injectors then your IVT terms need to be halved, also should not zero out the offset v inj tip temp table that could be your hot start issues if u have bigger injectors make that table stock and divide it by how bigger the injectors are from stock if they are double the flow then halve that table it wont be spot on but will be better then it is zeroed out

[twistedpixels]

if u have scaled your injectors then your IVT terms need to be halved, also should not zero out the offset v inj tip temp table that could be your hot start issues if u have bigger injectors make that table stock and divide it by how bigger the injectors are from stock if they are double the flow then halve that table it wont be spot on but will be better then it is zeroed out

My injectors are FIC 85lb. So that is basically double the size? SO just replace the inj temp data and cut it in half then? The thing is I think the tuner did scale the injectors differently. He did the double method for the AFR Stoich though. My old tune when the car was just head and cam with the same injectors and almost exact cam had the inj temp zerod and I did not have hot start issues at all.

My setup is:

440ci (LSR block bored 4.185)with 12.4:1 static and 9:1 dynamic
Callies custom finished forged crank 4" stroke and 6.125 Callies rods
stage 3 heads opened to 4.155 chambers w .044 quench
240/252 113+3 with .688" lift
Crower shaft rockers and Johnson short travel lifters
MSD intake ported and 102 TB with halltech 105 CAI
85lb Fuel injection connection injectors and Flex sensor
450 walbro
Lots of other things like coated pistons and piston oil squirters, Katech red pump, crank scrapper and Aviad oil pan mod and improved racing oil cooler.

The engine was built by a very good builder in Illinois and it was broken in on the engine dyno to seat the rings. It made 707/620.

[LSxpwrdZ]

The problem is here. The axis labels are wrong in the editor first of all. It is not 0, 25, 50, 75, 100. It IS 0, 10, 20, 50, 80

So going by your ethanol content you are still getting 60% of your Flex Adder table applied.
Flex Spark Multiplier.png

[LSxpwrdZ]

Flex Tab.png

Also want to touch base on some info here. The "Default Percentage" is the ethanol percentage used IF the sensor fails. So this needs to be set to a percentage that you 99% of the time plan on running. Meaning if you primarily keep it on ethanol fuel set it to something like 75-85%. Conversely if you run pump gas mostly then it needs to be set to 10%.

The Min/Max E% settings are the top/bottom limits of what the sensor will read and adjust the stoich point for. These parameters aren't enabled on all OS's meaning they don't seem to do anything at all on some OS's. It's best practice to leave sane values in them though. 0/100 is perfectly fine.

Transition and Delay volumes will have to be dialed in case by case basis. The closer the flex sensor is to the fuel rail the less these values need to be. If you run a return style system where fuel is flowing constantly through the sensor and rails then these settings need to be set to zero or very close to zero since there isn't a volume of fuel that needs to be consumed by the injectors in a dead head system (like stock returnless).

[twistedpixels]

Flex Tab.png

Also want to touch base on some info here. The "Default Percentage" is the ethanol percentage used IF the sensor fails. So this needs to be set to a percentage that you 99% of the time plan on running. Meaning if you primarily keep it on ethanol fuel set it to something like 75-85%. Conversely if you run pump gas mostly then it needs to be set to 10%.

The Min/Max E% settings are the top/bottom limits of what the sensor will read and adjust the stoich point for. These parameters aren't enabled on all OS's meaning they don't seem to do anything at all on some OS's. It's best practice to leave sane values in them though. 0/100 is perfectly fine.

Transition and Delay volumes will have to be dialed in case by case basis. The closer the flex sensor is to the fuel rail the less these values need to be. If you run a return style system where fuel is flowing constantly through the sensor and rails then these settings need to be set to zero or very close to zero since there isn't a volume of fuel that needs to be consumed by the injectors in a dead head system (like stock returnless).

Thank you for the info. My flex sensor is located right off the fuel rail but still using stock fuel system. So If I am going to switch between 100octane and e80 should I put default % at any specific amount? I am going to do this in order to try to keep build up on the back of the valves from the ethanol at a minimum. I had a major issue with that when I took the heads off to be redone for my new motor. Nearly had to get new intake valves the black gunk was so bad. I ran the car on e80 for 2 years straight.

If it were you what would you set these values to? I will run a half tank or more of 100 through it every few weeks.

Also I can not see a way to change the axis values in that multi vs comp. The edit option is grayed our when I right click and select row or column axis

I think I may want to get some remote tuning with you if possible. I still need to put my 2" ARH headers on and get my vacuum pump working again though. It is going to be a few weeks before I get both of those things done.

[LSxpwrdZ]

Thank you for the info. My flex sensor is located right off the fuel rail but still using stock fuel system. So If I am going to switch between 100octane and e80 should I put default % at any specific amount? I am going to do this in order to try to keep build up on the back of the valves from the ethanol at a minimum. I had a major issue with that when I took the heads off to be redone for my new motor. Nearly had to get new intake valves the black gunk was so bad. I ran the car on e80 for 2 years straight.

If it were you what would you set these values to? I will run a half tank or more of 100 through it every few weeks.

Also I can not see a way to change the axis values in that multi vs comp. The edit option is grayed our when I right click and select row or column axis

I think I may want to get some remote tuning with you if possible. I still need to put my 2" ARH headers on and get my vacuum pump working again though. It is going to be a few weeks before I get both of those things done.

The volumes will have to be dialed in to your application. Start off with 0.05 gallon in each of those. When you go to change from one fuel type to the other watch your fuel trims as the transition occurs. If stoich changes to quickly the fuel trims will show a sudden change due to the wrong stoich ratio being used for the fuel in the rail. Same will occur if it changes too slow. If you are on gas and fill up with ethanol and your fuel trims go positive during the transition then delay volumes are too high meaning it's not seeing the ethanol quick enough. Conversely if the fuel trims go negative during the transition then the delays are set too low.

The Axis don't get changed. They are fixed axis on your tune. What I'm saying is HPTuners has the axis labeled wrong. The labels are actually 0,10,20,50,80.

Hit me up if you'd like some remote tuning, [email protected]

[twistedpixels]

The volumes will have to be dialed in to your application. Start off with 0.05 gallon in each of those. When you go to change from one fuel type to the other watch your fuel trims as the transition occurs. If stoich changes to quickly the fuel trims will show a sudden change due to the wrong stoich ratio being used for the fuel in the rail. Same will occur if it changes too slow. If you are on gas and fill up with ethanol and your fuel trims go positive during the transition then delay volumes are too high meaning it's not seeing the ethanol quick enough. Conversely if the fuel trims go negative during the transition then the delays are set too low.

The Axis don't get changed. They are fixed axis on your tune. What I'm saying is HPTuners has the axis labeled wrong. The labels are actually 0,10,20,50,80.

Hit me up if you'd like some remote tuning, [email protected]

Ok that is more clear with the multi vs comp now. SO I should changed the 0, 25 , 50 all to "0" then if I do not want it to add any spark below 50% ethanol? When I get the headers in I will need some help to dial it in for sure. I will let you know. My biggest frustration is the hot start issues. Soon as it heat soaks for a few minutes it become very hard to turn over. Sometimes it just cranks and cranks then lazily fires up and sometimes I have to give it some gas to open the TB. The long cranks at hot start have lasted probably 5sec or more and either fails or slowly turns over. Hard to say if this is the starter getting too hot or in the tune. I did not have this issue before with heads and cam on e85 with the same exact headers and stock starter.

[07GTS]

I am going to do this in order to try to keep build up on the back of the valves from the ethanol at a minimum. I had a major issue with that when I took the heads off to be redone for my new motor. Nearly had to get new intake valves the black gunk was so bad. I ran the car on e80 for 2 years straight.

was this ethanol added after using petrol ? i found complete opposite when i switched to e85 my intake ports and valves look brand new no gunk at all like petrol leaves on them, if they had buildup from petrol the ethanol may try to mix with it causing a gunk ?

[twistedpixels]

was this ethanol added after using petrol ? i found complete opposite when i switched to e85 my intake ports and valves look brand new no gunk at all like petrol leaves on them, if they had buildup from petrol the ethanol may try to mix with it causing a gunk ?

Heads were redone once and used e85 before that only. then when I pulled the heads off for the new motor after another 1.5 years after being redone and cleaned they had massive build up. It is not regular gas doing it. I am not the only one that has had this black gunk residue from pump ethanol. They jacked up my injectors as well. E85 is not a great fuel to use all the time. The guy who does my heads has seen e85 do horrible things to valves and heads. He is not an idiot either. He has been doing heads for a long time and ports heads for some of the biggest engine builders in the nation. He told me to be careful with ethanol and titanium valves. Stainless steel exhaust valves can be cleaned no problem. The Stock Titanium intake valves have a special coating on them that if it gets removed from harsh solvents to clean them then they are junk.

[07GTS]

Heads were redone once and used e85 before that only. then when I pulled the heads off for the new motor after another 1.5 years after being redone and cleaned they had massive build up. It is not regular gas doing it. I am not the only one that has had this black gunk residue from pump ethanol. They jacked up my injectors as well. E85 is not a great fuel to use all the time. The guy who does my heads has seen e85 do horrible things to valves and heads. He is not an idiot either. He has been doing heads for a long time and ports heads for some of the biggest engine builders in the nation. He told me to be careful with ethanol and titanium valves. Stainless steel exhaust valves can be cleaned no problem. The Stock Titanium intake valves have a special coating on them that if it gets removed from harsh solvents to clean them then they are junk.

ok thats interesting ive been on pure e85 for a few years and it may be because mine is always from a barrel that its maby cleaner, im just building an engine now so i am changing it more to suit ethanol so ill keep the info in mind just encase