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The way a desired AFR map "should" work is to enrich the mixtures. ie 12:1 is an enrichment of around 22% over stoich. I haven't used the haltech software as I just dont like using them but if its anything like an autronic then changing the desired AFR map will result in a change of fuelling.

...but you'd need a wideband 02 sensor input into the ecu for it to know what AFRs it was actually running wouldn't you? Or am i not thinking about this correctly? Thinking i should get the Haltech wideband either way though.

Getting the car tuned on a 50/50 ethanol blend next week so i'll have a chat with the tuner when it's on the rollers.

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no point spending money on a wideband if your still gonna pay a workshop to tune it.

either buy a wideband and tune it yourself or spend the money on just a tune.

I believe there is a point - wideband's most basic use is to simply monitor AFRs to make sure nothing is out of whack. It will also plug into my ECU and I can set up out of range shut down in case anything goes wrong with an injector etc etc.

I will be learning / playing with the tune once I have the wideband - but I'm certainly not at the stage where I could tune from PULP to 50/50 ethanol myself.

After a few hours watching on they dyno i'll be much more confident and then have a PULP and a 50/50 ethanol tune to play around with and see if i can fine tune on the road.

Pretty much just another toy to play with... :D

if you do your research and keep to the safe side theres no reason you cant do your own tuning when you switch to ethanol mixes. its the way i did it and my tune is better than it ever has been

On this self tuning note...

I'm also a newbie with a wideband AFR gauge, works a treat and is great to see the needle drop down to 11.5-12 when my boost gauge goes up :(

but what sort of AFR's are you guys going for running full E85?

I know 14.5:1ish at low load and dropping to 11.5-12:1 on boost is the go for PULP, but where did this figure come from?

And how would ya know what figure one would be looking for when tuning for a 50/50 mix?

On this self tuning note...

I'm also a newbie with a wideband AFR gauge, works a treat and is great to see the needle drop down to 11.5-12 when my boost gauge goes up :(

but what sort of AFR's are you guys going for running full E85?

I know 14.5:1ish at low load and dropping to 11.5-12:1 on boost is the go for PULP, but where did this figure come from?

And how would ya know what figure one would be looking for when tuning for a 50/50 mix?

The figure will be the same. Your wideband meter is not reading afrs it is measuring the percentage of oxygen and expressing it as an air to fuel ratio. Although some wideband meters have the facility to change this if you leave it alone you will still be looking for the same numbers e.g. 14.7 stoich and around11-12 on boost regardless of the percentage of ethanol.

exactly. a wideband reads lambda, with 1 being 14.7 for petrol and around 9:1 for pure ethanol. if you leave your wideband set to petrol you can use the same figures as you would for tuning petrol, although you might be able to go a bit leaner (relative) with e85.

on cruise, and low loads i.e pre +ve pressure stoich is where you want to be at, I have my car tuned on the road 14.7 or there abouts for all light loads, and at 6k+ revs around 14k...

don't listen to all the haters, just do the right research first before playing around, generally with lighter loads, there is no need to pull back timing if you're leaning it.. also, if you're running close loop, you will notice that the ECU quickly finds stoich quite easily once you start doodling around.

I found out, from experience that the more close to stoich you tune your car and when closed loop is on, the ECU works out stoich much quicker therefore giving you much better efficiency.

As for coming onto boost, my a/f are roughly as follows:

- 3000 rpm: 14.7

- 3250 rpm: 14

- 3500 rpm: 13.5

- 3750 rpm: 12.5

- 4000 rpm: 12.0

I am pretty gangsta, I play it quite lean :thumbsup:

most people dont realise is that the highest EGT's are around stoich ie 14.4-15 either side of this AFR the combustion chamber temps go down.

this

1. buy a wideband

2. start reading and learning

3. save yourself shitloads of money by doing your own tuning, even for ethanol.

and this.

As for coming onto boost, my a/f are roughly as follows:

- 3000 rpm: 14.7

- 3250 rpm: 14

- 3500 rpm: 13.5

- 3750 rpm: 12.5

- 4000 rpm: 12.0

need to reference A:F ratio against boost, not RPM for the info to be relevant.

Lol. Guess how lean you are willing to go all depends on turbo / boost / power / $$ for a new engine... :P

just as a little fun fact, nissan (i think, may have been someone else) ran for 24 hours at le mans with a full load A:F ratio of 14.7:1. theres a miss conception around that being lean will kill your motor, it wont. it will increase EGT's and will have less of a cooling effect in the cylender causing it to knock and go bang, you can run it lean under load providing timing is set to match

if i was you, i'd run straight e85, and have a crack at tuning it yourself on the dyno. with the power your making you shouldnt make it knock, even if you give it a bit too much timing, power should fall away first

*dont take this as gospel, consult with a real tuner first lol*

this

and this.

need to reference A:F ratio against boost, not RPM for the info to be relevant.

just as a little fun fact, nissan (i think, may have been someone else) ran for 24 hours at le mans with a full load A:F ratio of 14.7:1. theres a miss conception around that being lean will kill your motor, it wont. it will increase EGT's and will have less of a cooling effect in the cylender causing it to knock and go bang, you can run it lean under load providing timing is set to match

if i was you, i'd run straight e85, and have a crack at tuning it yourself on the dyno. with the power your making you shouldnt make it knock, even if you give it a bit too much timing, power should fall away first

*dont take this as gospel, consult with a real tuner first lol*

I actually hit full boost around 3600 rpm, that's 1.3 bar

exactly. a wideband reads lambda, with 1 being 14.7 for petrol and around 9:1 for pure ethanol. if you leave your wideband set to petrol you can use the same figures as you would for tuning petrol, although you might be able to go a bit leaner (relative) with e85.

Just a quick question.

Youre suggesting to do a full tune on 50/50 on the street yes? How would you go about doing a full power tune on the road?

Fuel is easy obviously.

How would you tune the timing map? Using a knock box?

i use the standard knock sensors. some people seam to have a lot of trouble with them picking up absolutely every noise you can imagine but myne seam to work pretty well in that it only ever produces a high number when theres too much timing. pull timing and it always goes away.

the only time i get false knock readings are on limiter, but i simply ignore them as i've retarded the timing enough around limiter not to worry about knock there.

at the end of the day every ecu and every set of knock sensors is going to be different. a knock box would be ideal but some of us cant afford that sort of gear for tuning 1 car

i use the standard knock sensors. some people seam to have a lot of trouble with them picking up absolutely every noise you can imagine but myne seam to work pretty well in that it only ever produces a high number when theres too much timing. pull timing and it always goes away.

the only time i get false knock readings are on limiter, but i simply ignore them as i've retarded the timing enough around limiter not to worry about knock there.

at the end of the day every ecu and every set of knock sensors is going to be different. a knock box would be ideal but some of us cant afford that sort of gear for tuning 1 car

that's what I do as well for cells, for rows 18, 19, 20 I pull off 4 degrees of timing from row 17.. I'll put my values into an excel sheet and upload it when i get home

if i was you, i'd run straight e85, and have a crack at tuning it yourself on the dyno. with the power your making you shouldnt make it knock, even if you give it a bit too much timing, power should fall away first

Got advised not to run E85 from a bowser by my tuner - he says it's just been way too inconsistent when they've used it in cars - some come up great cause they arte actually getting E85, and others won't take anywhere near the timing. as obviously the fuel has separated or has water in it etc etc.

I can't really justify buying a whole drum of E85 for myself, i'll never go through it in time.

So I'm going to buy 100% ethanol from my tuner and mix a 50/50 blend when I want. He believes this is enough ethanol to get a lot of benefit with less worry about hoese / fuel pumps / fuel filter etc etc.

i use the standard knock sensors. some people seam to have a lot of trouble with them picking up absolutely every noise you can imagine but myne seam to work pretty well in that it only ever produces a high number when theres too much timing. pull timing and it always goes away.

the only time i get false knock readings are on limiter, but i simply ignore them as i've retarded the timing enough around limiter not to worry about knock there.

at the end of the day every ecu and every set of knock sensors is going to be different. a knock box would be ideal but some of us cant afford that sort of gear for tuning 1 car

IMO I think its extremely dicey to rely on factory knock sensors as they are produced on factory to detect knock at frequencies that are far different from those which occur in a modified engine setup ie turbos, exhausts, then internals etc etc.

Apart from the fact that pulling timing when knock is produced isnt an accurate way to tune timing under full load and wont give best results.

Each to their own but I dont think its fair suggesting a novice to tune his own car without proper use of a dyno.

Its nowhere near as simple as 'pay money for the hardware, do some reading, and tune the car yourself'.

Agreed it may be good for tuning cruise etc, but not for a full tune which includes full load cells.

Just something for the OP and other people considering tuning their own cars to consider.

on a mildly tune car, I find the knock pretty decent... whenever I see knock on the powerFC I can almost hear it and I've noticed with pre-dentontation you'll always feel a power loss...

It's better than using your ears to hear it, but by all means it's not gospel

How much can you get the pure Ethanol for if you don't me asking and which supplier is it from?

Can't remember exactly how much - will find out next Monday but i have the $2 figure in my head...?

Not sure where they get it from but i'll ask.

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