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E85 soon, tips?

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BLACK'98DSM

5+ Year Contributor
4,450
1,889
Feb 9, 2019
Alabama
As the caption says, I'm soon gonna start filling with E85. There is a station 25 miles away now!!!:hellyeah: Anyone have any pointers as to how I need to prepare? Anything special I need to do?

Also if anyone is using E85 on their 420a it'd be nice if they could tell me how it runs.
 
Fuel requirements are different than gasoline & the fuel system will need to be changed to supply more fuel for the same power levels & then more fuel for higher power output. You will need a way to tune spark & fuel to run E85. If you do not have a way to tune you should put off E85 and address a custom tuning method & a fuel system upgrade first. E85 will allow more timing advance which increase power. On an N/A engine that has not been modified with high compression pistons & is not ignition knock limited running E85 will not be a benefical as a turbo motor where the boost can be turned up.
 
What is your long term plan for this?
The other thing to consider is you won't necessarily gain power without higher compression or a forced induction when using e85. You will however use considerably more fuel.
E85 is something you'll need some considerable planning and mods for from where the cars at. The stock returnless fuel system isn't really set up for nor adequate for e85, so modifying that is going to be a rather large chore alone.
Engine tuning will require an aftermarket ecu (megasquirt comes to mind for 420a's), which again is fairly daunting.

I'd suggest making a goal for what you want the car to do and mod accordingly. Keep in mind this may put the car down for significant periods of time depending on how much you can work on it, so a spare vehicle is good to have.
 
I have been wanting to do this E85 for a while now. And the timing is perfect because they just built an E85 station near my city. I have my job bonus coming in next month so I will have a decent budget for modding. And yes I do have a spare vehicle to drive.
I can buy a 20 gallon fuel cell with a 255 fuel pump as a package.

My goal is to set the record for N/A 4 banger at Lassiter Mountain Dragway. Of course that's kind of far fetch'ed for a 420a, but even if I can come close then I will be satisfied.
 
What is the current record? If that’s your goal then by all means go for it, but I want you to know that you are in for a very expensive build and at the end of the day you will have a 200whp car. We have seen from other builds what it takes to break the 200whp mark on a 420a NA, and its not cheap. Plan on a built motor that is high compression, fully built head, and a megasquirt ECU just to start with.

E85 is an entirely separate topic. People switch to E85 because they are at the limits of 93 pump gas. With a higher octane fuel they can add some timing back in and get substantial gains. The fuel itself does not increase engine power. When you get into tuning and adjusting ignition timing, you will hear people talk about MBT (Max brake torque), this is the timing value that will give you the most torque at that point on the map. On a steady state dyno you can watch the torque values increase as you increase timing, once you get past MBT, the torque will start to fall off again. Ideally you would run MBT timing for every rpm point at WOT to make the most power. Unfortunately most run into knock before they ever get to MBT. This leave some power on the table if you choose to go to a better fuel. Now, on a NA car running 93. You may be able to get to MBT before running into knock, hell the 420a may already be there from the factory. I have no idea how close the 420a was stock because I never did any tuning on it before I added a turbo, and then built my timing map accordingly.

I say all of this so you can understand that just throwing parts at the car may not get the results you are after.
 
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