Camaro E85 Cold Start

[Balakayt.]

I helped my buddy switch his Camaro over to E85 back in the summer. Here in Texas it ran great in the summer but hes complaining of a long crank now. Morning temps in the upper 40s low 50s. Its a 2018 Camaro SS. NA 6.2. Has CAI and long tubes no cats. We live about an hour apart and unfortunately i don't have a log to work with. I just kind of wanna make sure im on the right track of what is needed.

After reading around here it seems on E85 cold start issues the 3 main things would be cranking fuel, cranking spark and maybe 02 settings.

In the cranking spark advance table i pulled about 3 degree out of the area in blue. (This is just an initial change hopefully im on the right track).

a.png

Moving over to the cranking EQ ratio. The normal and alcohol tables are different. And to me it already looks very rich in the colder ECT area. Would it still need more fuel below say 60 degrees ECT ??

b.png

Right now all of the injection timing is stock. Is there any need to adjusted the SOI Cranking tables? Cranking SOI sooner or later?

He says it doesn't stumble or stall after it starts but it also is not very cold yet here in Texas. I know yall hate assholes who don't upload logs but any info or suggestions would be appreciated. Here is the current toon in it.


CURRENT launch control.hpt

[edcmat-l1]

I would not reduce the cranking timing.

O2 settings have nothing to do with start-up.

I'd concentrate on cranking fuel.

The colder it gets the less E85 wants to vaporize. At a certain temp it's just not going to fire off like it will on petrol.

[TriPinTaZ]

Add timing in the alcohol cranking adder table and not the main Cranking Spark table.


What % of E is in the car?

[1scls1z]

Simple solution would be to reduce the ethanol content. Drop it down to E50-60, I promise you are not losing much performance by doing so. That being said you need more cranking spark not less to ignite cold ethanol.

[GHuggins]

That depends. I've had really good luck with putting crank spark around 3 to 5 degrees on cammed motors, so it ignites at the most concentrated and highest compression possible and those have added timing for the regular crank table due to the cams. Requires adding some fuel too and sometimes double over stock in colder temps, but they fire right up in 0 temps with full ethanol. Stock cams seem to do better with more timing or timing being added. It's an either/or...

This one was completely dialed in. Has a cam... Fires right off with full E70 to E75, which is what you actually get in the winter vs full E85...

Crank Spark with cam.jpg

Fuel.jpg

[Balakayt.]

What % of E is in the car?

He is consistent on getting gas at the same station and surprisingly I was reading 65 - 70% from a pump which is pretty good here in DFW.

That depends. I've had really good luck with putting crank spark around 3 to 5 degrees on cammed motors, so it ignites at the most concentrated and highest compression possible and those have added timing for the regular crank table due to the cams. Requires adding some fuel too and sometimes double over stock in colder temps, but they fire right up in 0 temps with full ethanol. Stock cams seem to do better with more timing or timing being added. It's an either/or...

This one was completely dialed in. Has a cam... Fires right off with full E70 to E75, which is what you actually get in the winter vs full E85...

I had read els where that reducing timing helped on cold start so that makes sense. I never would have guess adding that much fuel cranking would help make it better. Thanks for the screen shots those are going in my notes for sure.

I appreciate everyone's reply's.

I had him time the cold start this morning in 38 degrees and it had a 3-4 second crank..... I told him to stop worrying for now lol.

[TriPinTaZ]

I've have luck with increased timing on the higher compression engines. However, Ghuggins tunes cars in much colder temps than most of my clients see.


Have you tried moving split factor cranking SOI and EOI around. Basically try spraying the first pulse sooner and move more fuel to the first pulse, then move the second pulse a little bit later.

[GHuggins]

Have you tried moving split factor cranking SOI and EOI around. Basically try spraying the first pulse sooner and move more fuel to the first pulse, then move the second pulse a little bit later.

Now you're talking something I want a lesson on remember pictures please and have you had good luck moving that around I take it
I honestly normally killed the multi pulse for crank so maybe something im doing wrong all together..

[TriPinTaZ]

Well it is my unproven theory that if you increase timing, you're firing off sooner but then that gives the e85 less time to atomize or light off if you're spraying later or more fuel on the second pulse.

My idea is around these tables which are from my 2023 ZL1. They are different than past year LT stuff and have no issues cold cranking E85. If you compare these values to say an early LT1 truck or LT1 Corvette, they are vastly different. Even though it is an LT4, its not like the blower is spinning fast enough to make much of a difference on startup. It seems like they are pushing the fuel around to get the best chance at light off even on just pump gas.


Again, none of this is tested but its something I found interesting.

Screenshot 2024-11-16 135844.png

[GHuggins]

Well it is my unproven theory that if you increase timing, you're firing off sooner but then that gives the e85 less time to atomize or light off if you're spraying later or more fuel on the second pulse.

My idea is around these tables which are from my 2023 ZL1. They are different than past year LT stuff and have no issues cold cranking E85. If you compare these values to say an early LT1 truck or LT1 Corvette, they are vastly different. Even though it is an LT4, its not like the blower is spinning fast enough to make much of a difference on startup. It seems like they are pushing the fuel around to get the best chance at light off even on just pump gas.


Again, none of this is tested but its something I found interesting.

Screenshot 2024-11-16 135844.png

I've only got a few 23's in my files and they looked the same all the way back to the 18's that I compared to. Is yours a newer 23 by chance? I thought I had your stock file to look at, but not sure now It would make more sense to inject the majority later like you're saying.

[TriPinTaZ]

Mine was the last run of 2023's built before the 2024's came out. I think I sent you my file when we were looking for User Defined Parameters. If not I can send it to you.

[GHuggins]

If you don't mind or post it on here either one. I obviously misplaced it if that's the case. I remember looking at the OS number, but don't think I saved it. I guess it's safe to say yours is a 24 then?

[TriPinTaZ]

Emailed you the file

[Balakayt.]

Would a value of 1.00 in those Split Pulse Factor tables mean 100% is injected on the second pulse?