E85 Question
Racer
Joined: Oct 2021
Posts: 389
Likes: 76
From: Chicago
This u should goggle a ton of info on this topic over the yrs. Trust me u'll know everything that u need and then some. way to many different set ups depending on hp goals and price.
Thread Starter
Instructor
Joined: Nov 2011
Posts: 195
Likes: 7
From: Sneads Ferry NC
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
you can do a dedicted e85 tune, but measure the E so see if it checks out. E is more friendly but quality and consistency vary.
what are your goals and build?? E85 works great for FI and racing higher than stock compression ratios, but not worth much on a stocker
you need all e85 compatible stuff and very high flow pumps. since you are FI, budget for a complete fuel system with a return regulator if you don't have one.
Also consider flex fuel as it's a great way to go, but you need at a minimum the 04 ecm and more mods or a dedicated aftermarket ecm which is really the way to go for flex fuel.
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
OR you can consider dual fuel. Modifying the vette fuel system is a pita and expensive.
Holley now has a slick high rpm dual injector/dual fuel rail intake manifold that makes dual fuel very possible
you retain the stock gas side for startups and off boost, and trigger another dedicated set of injectors for pure meth injection in all 8 ports
a megasquirt or a variety of aftermarket ecms will work as you are triggering the additional fuel flow based on boost only operation and you can still use the wide bands to help trim
since the narrow band ecm only references the tables at wot, not o2 (narrow band anyway) it should work just like any other meth system only better. You can build in safe guards as this will clearly be a "meth dependent" tune
the o2s and other alarms in the megasquirt work great there. Any the fuel system mods are much easier. Another dedicated tank for the alchy, a big pump, and NO mods to the factory fuel system or injectors.
I haven't gotten much feedback, but it sure looks like a good think to try.
Holley now has a slick high rpm dual injector/dual fuel rail intake manifold that makes dual fuel very possible
you retain the stock gas side for startups and off boost, and trigger another dedicated set of injectors for pure meth injection in all 8 ports
a megasquirt or a variety of aftermarket ecms will work as you are triggering the additional fuel flow based on boost only operation and you can still use the wide bands to help trim
since the narrow band ecm only references the tables at wot, not o2 (narrow band anyway) it should work just like any other meth system only better. You can build in safe guards as this will clearly be a "meth dependent" tune
the o2s and other alarms in the megasquirt work great there. Any the fuel system mods are much easier. Another dedicated tank for the alchy, a big pump, and NO mods to the factory fuel system or injectors.
I haven't gotten much feedback, but it sure looks like a good think to try.
Thread Starter
Instructor
Joined: Nov 2011
Posts: 195
Likes: 7
From: Sneads Ferry NC
I've been resisting, but ok. Upgrades to the fuel system and injectors. E85 will take 30% more volume, size your fuel system for that and then some you can do a dedicted e85 tune, but measure the E so see if it checks out. E is more friendly but quality and consistency vary. what are your goals and build?? E85 works great for FI and racing higher than stock compression ratios, but not worth much on a stocker you need all e85 compatible stuff and very high flow pumps. since you are FI, budget for a complete fuel system with a return regulator if you don't have one. Also consider flex fuel as it's a great way to go, but you need at a minimum the 04 ecm and more mods or a dedicated aftermarket ecm which is really the way to go for flex fuel.
Burning Brakes
Joined: Mar 2006
Posts: 837
Likes: 260
From: Omaha NE
Mine is setup to run E98 now I ran E85 before that. I will tell you from experience even living in Corn country Nebraska finding actual E85 is damn near impossible. Just in the last year I am lucky to find E70 at the pump. I finally switched to race grade E98. That said if I am going to just putz around town and stay out of boost I will run pump stuff.
Race Director
Joined: Apr 2007
Posts: 18,048
Likes: 53
From: long Island NY
No expert but know a little.
The C5's don't have progressive computers so its not easy and or cheap to do this.
Another issue, E85 IN stations can be shitty, I know many people who test prior to filling with not so great results.
If you can't run both at will you can also be limited if you want to take the car for a long trip where finding E85 can be hard or impossible.
Unless you have crazy HP goals, tuning for 93 with Meth is quite simple and cheaper. You really don't need Meth, but Meth is good insurance for bad gas, and stock to mild built motors.
I been running 600 to the wheels stock LS6 Centri car since 07' with no issues and only recently had to replace Meth Pump which was easy and not expensive
The C5's don't have progressive computers so its not easy and or cheap to do this.
Another issue, E85 IN stations can be shitty, I know many people who test prior to filling with not so great results.
If you can't run both at will you can also be limited if you want to take the car for a long trip where finding E85 can be hard or impossible.
Unless you have crazy HP goals, tuning for 93 with Meth is quite simple and cheaper. You really don't need Meth, but Meth is good insurance for bad gas, and stock to mild built motors.
I been running 600 to the wheels stock LS6 Centri car since 07' with no issues and only recently had to replace Meth Pump which was easy and not expensive
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Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,455
Likes: 7,154
From: CT
How are the P59 ecu conversions for running ethanol?
It sounds as though the ethanol question in this case is almost moot since the fuel system was already paid to be serviced at likely great expense. Unless you're doing it yourself it seems a needless expense to go back into the tanks a second time. You'd ideally want a return style fuel system, larger rails, injectors, another pump preferably in-tank but it could be external also, and you'd have to bust into the passenger tank to remove the factory fpr for a return style system regardless.
I'd just pulley down when you're ready and tune for 93. Consistent pump quality, accessible everywhere, no invisible blue flame in an accident from a methanol tank if you go that route. Unless you intend to really wind the car up I don't think ethanol is necessary. But maybe that's the eventual goal, in which case.... revisit everything above.
It sounds as though the ethanol question in this case is almost moot since the fuel system was already paid to be serviced at likely great expense. Unless you're doing it yourself it seems a needless expense to go back into the tanks a second time. You'd ideally want a return style fuel system, larger rails, injectors, another pump preferably in-tank but it could be external also, and you'd have to bust into the passenger tank to remove the factory fpr for a return style system regardless.
I'd just pulley down when you're ready and tune for 93. Consistent pump quality, accessible everywhere, no invisible blue flame in an accident from a methanol tank if you go that route. Unless you intend to really wind the car up I don't think ethanol is necessary. But maybe that's the eventual goal, in which case.... revisit everything above.
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
another way to do this pump gas tune at 6000 rpm limit
e85 tune with 7500 rpm limit to get to hgher boost
I think I'll start with pump gas, even at 6000 it will be enough and e85 for the kill tune
e85 tune with 7500 rpm limit to get to hgher boost
I think I'll start with pump gas, even at 6000 it will be enough and e85 for the kill tune
Running Guns & Moonshine
Joined: Aug 2001
Posts: 12,455
Likes: 7,154
From: CT
Right there I have a new concept in mind. Different rpm limits for different curves. I have the valvetrain to fly to the moon, I just wonder how high the old by current standards jam cam will continue to make power. And how far beyond the 52k rpm limit the vortech would survive. I have to check, but I think I have it redlined by 6500 with the pulley combo between IW and head unit being equivalent to a stock hub and a 3.27"
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
I'm running a P59 with flex fuel, it's a decent solution. You can at least correct fueling for inconsistent ethanol content and auto adjust spark based on E content as well. However you're still limited to narrowband fueling. Aftermarket ECU will allow things like closed loop dual widebands and more flex fuel related features and safeties. But P59 is also nice if it's a direct swap and everything still works and functions as intended for cheap and not too much effort.
Race Director
Joined: Dec 1999
Posts: 10,230
Likes: 885
From: Alexandria, Virginia, USA VA
I have an older Platinum 2000 but it has great flex fuel support. I need to just get it together and install it. I hate wiring and am going to crimp not solder to get by it.