Practical Experience? Afr And The Effect Ethanol (e5 Or E10) Has?

[benl1981]

Anybody done this back to back testing.

E.g. Shell 98 AFR 12:1, then run shell extreme (E5) and checked how much the AFR had moved?

Anybody done this with E10?

Is the AFR change enough to warrant a retune? Or most of the time ok if tune was to 11.8:1 AFR with optimax?

Thanks

Edited October 11, 2006 by benl1981

[cameron]

Yep,

Leaner mixtures straight up!

Martin donnon did a write up in hpi I think.

[rob82]

And from this did he deduct that a leaner mixture increased EGT when run on the same tune? There is three things your have to wieght up 1. is the less density of the Ethanol 2. the fact that alcohols generally produce lower EGT's. 3. How much oxygen the ethanol is carrying.

[benl1981]

So how much would the AFR move on an R33gtst making about 170-180rwkw?

[Busky2k]

From my experience with a wideband, the AFRs moved about ~0.3-0.4 leaner using E10. E5 would be half of this.

Edited October 12, 2006 by Busky2k

[benl1981]

From my experience with a wideband, the AFRs moved about ~0.3-0.4 leaner using E10. E5 would be half of this.

Thanks Busy2k - thats the kind of info I was chasing.

So its not that significant.

i.e. If the tune is safe with normal 98 (i.e. 11.8:1) then it should still be safe running boost98 (E10) it sounds like. I think the ethanol lowers the EGTs slightly anyway?

[Abo Bob]

Since you have to up the timing anyway - I presume by using the ignition correction on the pfc - then can't you increase the injectors by some amount - also in the correction bit - to lower the AFR and thus make the tune happy again?

You would have to remember to do it every time you turned the car on though.

[Busky2k]

Yep by putting in the E10 it should be still quite safe. But to get the most out of it, you may have to up the ignition timing 1 or 2 degrees. Changing the fuel injector correction (ie from 50 to 51% if using 740cc injectors) should be enough to offset the changes in AFR. A dodgy way to permanantly increase the ignition timing is to advance the CAS 1 or 2 degrees if you have a timing gun.

[Cubes]

Busky2k,

Have you checked out the optimax extreme down at Findon?

http://www.coles-express.com.au/locator.asp

Its supposed to be sorted by the 18th of Sept..

[Busky2k]

Nope. Its available in Adelaide? OoooOoOoOooo.... who wants to be a test MULE!