E85 basics

[blu3man]

Ok,

So while buying new injectors I found a perfect set of 900cc injectors for really cheap.

Since I have the injector capacity to run E85 and the fuel pump, why not run it?

So I have a few questions:

a) What are the AFRs I should be aiming for in E85? (idle, spool, midspool, and full boost)

b) Should I add in any oil to my fuel (cylinder lubricant)

c) Will an E85 engine spool slower then a RON98 engine? (due to less heat)

d) Does anyone have an S13 SR20det example tune of timing figures, I need to know where I should add extra timing and how much.

e) Is pump 85 ok to use? Or should I stick with barrel?

f) From the mods below, Am I missing anything which will inhibit my E85 use?

Mods:
900cc sard inj, walbro pump, arc fmic, SR20 DE cams (na ones), PE1420 turbo, 3" straighthrough exhaust, boost controller

In pieces and not yet tuned. I have began my yearly upgrade since the motorsport season has ended. (this is a big upgrade from my trusty t25 setup...)

I have no idea about E85 apart from it being a proclaimed wonderfuel, you can run more timing, it runs cooler and you need more of it.

[STATUS]

Ok,

So while buying new injectors I found a perfect set of 900cc injectors for really cheap.

Since I have the injector capacity to run E85 and the fuel pump, why not run it?

So I have a few questions:

a) What are the AFRs I should be aiming for in E85? (idle, spool, midspool, and full boost)

b) Should I add in any oil to my fuel (cylinder lubricant)

c) Will an E85 engine spool slower then a RON98 engine? (due to less heat)

d) Does anyone have an S13 SR20det example tune of timing figures, I need to know where I should add extra timing and how much.

e) Is pump 85 ok to use? Or should I stick with barrel?

f) From the mods below, Am I missing anything which will inhibit my E85 use?

Mods:
900cc sard inj, walbro pump, arc fmic, SR20 DE cams (na ones), PE1420 turbo, 3" straighthrough exhaust, boost controller

In pieces and not yet tuned. I have began my yearly upgrade since the motorsport season has ended. (this is a big upgrade from my trusty t25 setup...)

I have no idea about E85 apart from it being a proclaimed wonderfuel, you can run more timing, it runs cooler and you need more of it.

E85 is nice. Expect good gains on your setup (270rwkw ish). I prefer using the new range of ID injectors as they are far more efficient than the older style injectors like the sards etc..

we can get a near perfect idle on small capacity engines with ID1000 and ID2000cc injectors, infact the id2000 idle better than the sard 1000cc injectors and are double the size.

The id1000's will idle better than most older skool injectors around the 555cc size... they are quite impressive.

Be aware that e85 from the pump varies in composition from e70-e85 so ask the attendant the approx mix and tune accordingly.

[Zuikkis]

a) What are the AFRs I should be aiming for in E85? (idle, spool, midspool, and full boost)

If you are looking at wideband AFR, you can tune to similar values as gasoline.. 14.7 idle, 12 at boost. Perhaps a little bit leaner on boost, like 12.5-13 even..

[HermaN]

c) Will an E85 engine spool slower then a RON98 engine? (due to less heat)

d) Does anyone have an S13 SR20det example tune of timing figures, I need to know where I should add extra timing and how much.

c) I would imagine it might be maginally slower, but only by a couple hundred RPM, if that....

d) Normal tuning rules apply really. Keep adding timing until you reach MBT and leave it at that. Unlike pump fuel, you will not be knock-limited by E85, so you could easily go past MBT. Other than that, it should be no different to tuning for normal fuel.

[PL]

You've gotta be careful when tuning AFR's with E85 because stoichiometric is around 9.7:1. You want 8.2 - 8.3:1 AFR at full load. But your wideband needs to be set up for this - it'll use stoichiometric of 14.7:1 unless you tell it otherwise. So it'll show 12.35 AFR when in reality it's 8.2.

Confused? I was. For this reason I use Lambda when tuning E85 - and aim for around 0.84 to 0.85. Much less confusing! I've heard that you can go leaner without a problem but haven't experimented much personally. From what I've seen it is a very flexible fuel to tune with. I've gone lots richer than 0.84 lambda with minimal power loss. Same with timing - not nearly as critical as "normal" petrol.

I've not tried this but people have said that you can improve boost response by actually removing timing in that area - idea being that retarded timing increases EGT and hence makes more exhaust gas to get things spinning up.

I don't have massive E85 tuning experience but a rule of thumb so far seems to be that adding 5 degrees to start with isn't a problem. As Herman said - add timing until torque stops increasing.

Somebody made an interesting comment about watching EGT's and it's got me thinking. Slower burning fuel means you're more likely to end up with higher EGT's. Unfortunately I rarely have the luxury of being able to monitor EGT's but may need to go this way for high power jobs.

The big things to watch with E85 are fuel system contamination and fuel consistency. When you change over to E85 it's a good idea to keep a close eye on your fuel system. Change the filter after a tank and then again after a couple more tanks. It will cause any rubbish in the tank (that usually floats around harmlessly) to go into solution and then get sucked through the pump/filter. Once this "purge" is done you're usually OK.

The big one here in SA has been fuel consistency. Problem being that it sits around in the underground tanks too long and goes stale. The ethanol causes it to take on moisture and then it loses it's effectiveness. If you have good turnover at your local pump then you'll be fine. But if things are a bit slow (I'm in Adelaide, so everything is slow!) then you gotta watch it. This is why local guys running E85 are now just buying it in 200l drums and treating it as a race fuel. Including draining the tank between track days and storing the fuel in sealed containers.

GM have now released thei flex-fuel vehicles here - and done some sort of deal with Caltex. So there are more places starting to keep E85 and hopefully the turnover will increase. There'll need to be some sort of incentive to use it though cos your average Joe won't be interested once he realises that his range is decreased by 20 to 30%.

PL

[Zuikkis]

You've gotta be careful when tuning AFR's with E85 because stoichiometric is around 9.7:1. You want 8.2 - 8.3:1 AFR at full load. But your wideband needs to be set up for this - it'll use stoichiometric of 14.7:1 unless you tell it otherwise. So it'll show 12.35 AFR when in reality it's 8.2.

Confused? I was. For this reason I use Lambda when tuning E85 - and aim for around 0.84 to 0.85. Much less confusing!

For the same reason, I like to tune with gasoline AFR's.. So if 12.35 AFR is good for gasoline, it's good for E85 as well.. Of course it is not "real" AFR, but that's not really important?

[STATUS]

You've gotta be careful when tuning AFR's with E85 because stoichiometric is around 9.7:1. You want 8.2 - 8.3:1 AFR at full load. But your wideband needs to be set up for this - it'll use stoichiometric of 14.7:1 unless you tell it otherwise. So it'll show 12.35 AFR when in reality it's 8.2.

Confused? I was. For this reason I use Lambda when tuning E85 - and aim for around 0.84 to 0.85. Much less confusing!

For the same reason, I like to tune with gasoline AFR's.. So if 12.35 AFR is good for gasoline, it's good for E85 as well.. Of course it is not "real" AFR, but that's not really important?

or learn in lambda

[LooseEndsDrifters]

I have mine tuned on e85. it is road (track) tuned only and id like to see what other sr20 timing maps look like with e85. Can someone put some up??

[PL]

I'll dig some out tonight. I've found mine vary a lot though - depending on the quality of the fuel I suspect. Mine tend to finish up at about 5 degrees more than a 98 tune. But some will take lots more.

We have Caltex eFlex locally and tuning this as E85 is fraught with danger as ethanol content varies a lot. You really need an ethanol content sensor cos it varies from E85 down to below E70. I noticed on a pump the other day that they actually say ethanol content 70 to 85%.

PL

[PL]

For reference - S13 SR20DET, 98 RON fuel, 56t 2871, 264 cams, 740cc inj, 18psi:

S13 SR20DET IGN 98 18psi.jpg

(56.99 KiB) Downloaded 9374 times

Same car as above but on E85:

S13 SR20DET IGN E85 18psi.jpg

(55.06 KiB) Downloaded 9374 times

Another S13 in similar sort of tune running E85:

S13 SR20DET IGN E85 18psi AN.jpg

(57.55 KiB) Downloaded 9374 times

[PL]

Another S13 running 2871, 264 cams, 850cc inj, ext WG, E85:

S13 SR20DET IGN E85 19psi CS.jpg

(56.81 KiB) Downloaded 9374 times

[LooseEndsDrifters]

Thanks pete

[bachig24u]

What's the compression ratio?

Ok,

So while buying new injectors I found a perfect set of 900cc injectors for really cheap.

Since I have the injector capacity to run E85 and the fuel pump, why not run it?

So I have a few questions:

a) What are the AFRs I should be aiming for in E85? (idle, spool, midspool, and full boost)

b) Should I add in any oil to my fuel (cylinder lubricant)

c) Will an E85 engine spool slower then a RON98 engine? (due to less heat)

d) Does anyone have an S13 SR20det example tune of timing figures, I need to know where I should add extra timing and how much.

e) Is pump 85 ok to use? Or should I stick with barrel?

f) From the mods below, Am I missing anything which will inhibit my E85 use?

Mods:
900cc sard inj, walbro pump, arc fmic, SR20 DE cams (na ones), PE1420 turbo, 3" straighthrough exhaust, boost controller

In pieces and not yet tuned. I have began my yearly upgrade since the motorsport season has ended. (this is a big upgrade from my trusty t25 setup...)

I have no idea about E85 apart from it being a proclaimed wonderfuel, you can run more timing, it runs cooler and you need more of it.

[STATUS]

Best to run united if possible. We go through 100 to 150l Tuning with it and test it 3 times a week. It's very consistent.

[PL]

Yeah I always recommend United here in Adelaide - and actively steer people away from Caltex.

Trent, what ethanol % do you see from United E85? Is it always E85 or does it vary as well?

PL