Nistune Forums

Who is using E85 on an CA18DET?

What are your experiences?

How much do you advance your timing in compare to petrol (98-100 octane)?

In the absence of any other replies I'm happy to add my 2c worth...

I've only done SR20's on E85 but in my experience E85 results - phenomenal!

Unfortunately there are many downsides to E85, but done right it is a turbo engine's very best friend.

There's no real quick answer to your question but on average on an SR I've added minimum 5 degrees. But I've also seen up to 15 degrees extra at full load! It's hard to know how much to add cos you usually won't hear detonation. Rather than search for the detonation threshold, tuners I know will simply watch the torque curve and add timing until torque stops increasing. No point adding more than that.

The main problem I've seen with E85 (here in Oz anyway) is consistency. If you get a good batch (ie: fresh) then you can do no wrong. It'll take lots of timing, there'll be no detonation and you'll make buckets of power. Get a bad batch and you'll struggle to do much better than 98RON pump fuel.


The serious guys are now buying E85 in 200l drums only from race fuel suppliers rather than from the pump to ensure consistency.

PL

PL wrote:In the absence of any other replies I'm happy to add my 2c worth...

I've only done SR20's on E85 but in my experience E85 results - phenomenal!

Unfortunately there are many downsides to E85, but done right it is a turbo engine's very best friend.

There's no real quick answer to your question but on average on an SR I've added minimum 5 degrees. But I've also seen up to 15 degrees extra at full load! It's hard to know how much to add cos you usually won't hear detonation. Rather than search for the detonation threshold, tuners I know will simply watch the torque curve and add timing until torque stops increasing. No point adding more than that.

The main problem I've seen with E85 (here in Oz anyway) is consistency. If you get a good batch (ie: fresh) then you can do no wrong. It'll take lots of timing, there'll be no detonation and you'll make buckets of power. Get a bad batch and you'll struggle to do much better than 98RON pump fuel.


The serious guys are now buying E85 in 200l drums only from race fuel suppliers rather than from the pump to ensure consistency.

PL

at the moment I added 5 degree more timing and lambda 0,7 under full load, I think thats quite "save"

I know that you don´t can hear any knock, you can just blow your head gasket with to much timing


How have you managed the fuel Map, that it shows you the right lambda values?

in the DC view I added about 25% more and it worked quiete well, but i don´t like the incorrect view.

Lambda 0,8 instead of Lambda 1
Lambda 0,55 instead of 0,75

I´m not sure if it would be right to change the k-consant, because for my understanding ther is only one right k-constant value.

You really need to be monitoring torque with each timing change, but yes I'd say 5 degrees would be pretty safe.

I tune for 0.82 lambda at full load, although E85 doesn't seem to care too much about AFR changes - I've run it very rich with no appreciable loss in power. You'd probably wanna be monitoring EGT if you leaned it out any more than 0.82 though.

Just change you K constant, not fuel map figures. You want about 30% more fuel under all situations, so K constant is the place to do it. You'll also need to play around with cold start.

PL

PL wrote:You really need to be monitoring torque with each timing change, but yes I'd say 5 degrees would be pretty safe.

I tune for 0.82 lambda at full load, although E85 doesn't seem to care too much about AFR changes - I've run it very rich with no appreciable loss in power. You'd probably wanna be monitoring EGT if you leaned it out any more than 0.82 though.

Just change you K constant, not fuel map figures. You want about 30% more fuel under all situations, so K constant is the place to do it. You'll also need to play around with cold start.

PL

But how do i know If my DC is to high? I have given 25% more over the full map.

Zenki wrote: But how do i know If my DC is to high? I have given 25% more over the full map.

You shouldn't touch the fuel map, just use the same map as for petrol. Then adjust K value (Injector multiplier) 25-30% higher and it should be fine.

It will affect load scaling though. You could simply select "change injectors" from the menu, and decrease injector size -30%.. Then NIStune will calculate the new injector multiplier and fix the scales.

If your Inj Duty Cycle is to high you'll find that it leans out at high RPM.

Just do a log of a full power run and you'll see pretty quickly.

PL

PL wrote:If your Inj Duty Cycle is to high you'll find that it leans out at high RPM.

Just do a log of a full power run and you'll see pretty quickly.

PL

But normally you should use an max. DC from 90%, for a save setup

I recently shifted to E85 and can confirm everything in this thread. Well done everyone.

For those interested in boosting NA blocks, as a small project, I recently installed a high comp (12:1 higher than stock) NA motor (Stock internals) and tuned it for 14 PSI on 98 Oct fuel with very aggressive timing map.

Swaped over to E85 this weekend and am now running 18psi, with an additional 5deg timing and is perfect even on a hot day.

My old K setting was was 7F (hex)and new setting 90 (hex).

Corrected AFR with "K" set to 7F was above 20, with ECU set to 90 corrected AFR is 12.5.....

You all really need to check you EGT when adjusting timing map with E85 because E85 burns much slower then gasoline you will almost certainly run very high EGT temperatures when you switch to E85.

When I started mapping for E85 I quickly saw the EGT rise to over 1100 degrees Celsius, we added more pre ignition timing and the temperature went down. I now have 32 degrees pre ignition on full load and about 870 degrees EGT.

Your piston rings or conrods will probably break before you hear knocking on E85


Regards
John

John wrote:You all really need to check you EGT when adjusting timing map with E85 because E85 burns much slower then gasoline you will almost certainly run very high EGT temperatures when you switch to E85.

When I started mapping for E85 I quickly saw the EGT rise to over 1100 degrees Celsius, we added more pre ignition timing and the temperature went down. I now have 32 degrees pre ignition on full load and about 870 degrees EGT.

Your piston rings or conrods will probably break before you hear knocking on E85


Regards
John

How does it sound when E85 knocks? Like unleaded?

Is it possible to dedect it with an common system like the ks 4 from Phormula?

It doesn't.

PL

PL wrote:It doesn't.

PL

Maybe you can describe it?

Is it possible to dedect it with an common system like the ks 4 from Phormula?

I've just never been able to detect knock with my little microphone setup. And I've tried.

I was experimenting with an SR20 one night - I had a very experienced tuner with me and we were adding timing purely to see where knock would occur. We got to 35 degrees on full boost and just looked at each other in amazement. There was no knock. I'd be impressed if any electronic form of knock monitoring would pick it up.

So we went back to only adding timing until torque stops increasing. Which I must admit does seem to vary a lot. Average seems to be 5 to 10 degrees on top of what you'd run with 98.

PL

Hi guys,

just adding my 2p here.

I am running e85 in my ca18det and have been for years. Wonderful thing, and my fuel system has never been cleaner.

I am currently having some problems with my ECU as the 44F07 ECU does not have the same program than the other ECUs ... which means the address file is different.

Anyway, little thread highjack here, i have an EGT sensor. Is there a way to install it without removing the head or the exhaust header ? the reason is that i just reassembled the engine, and i dont want to open it again, or remove the OEM exh manifold... I know there is a big screw in the head that leads just after the 4th cylinder exhaust valve, but it looks the engine (or the head) has to go out to remove and fit the sensor here ... Any idea ?