E85 in your GT4

[749dark]

Hi all,

Is there any material available about running E85 in your GT4? Would there be any possible safety concerns about adding some of this fuel in the tank?

Thanks

Al

[MFX]

I am not sure of the GT4 specifically, but you have to be sure that all of the hoses and seals are safe for Ethanol as it will make a mess of them if they aren't. The other side is there is not a huge benefit of running E85 on an NA vehicle, to be worth the hassle. E85 is a prefect match for forced induction though.

[tomo]

On 16/04/2023 at 12:19, MFX said:

I am not sure of the GT4 specifically, but you have to be sure that all of the hoses and seals are safe for Ethanol as it will make a mess of them if they aren't. The other side is there is not a huge benefit of running E85 on an NA vehicle, to be worth the hassle. E85 is a prefect match for forced induction though.

I have heard that 3 gallons of water to 1 gallon of ethanol doesn't make a bad Vodka, The ratio could need adjusting though , 🤔 

[AAAC]

I am not an authority on this so take i this post with a large pinch of salt.

 I have heard that E85 ethanol content varies quite a bit during its storage and then with what is already in your tank.
 

The car needs a ’flex fuel’ sensor to determine the composition of the fuel in the lines so it can adjust the amount of fuel injected accordingly, which is greater with E85.

The injectors and fuel pumps would need to have this reserve capacity. The engine computer would need reprogramming, if it indeed has the allowance for flex fuel maps. 
 

I would hazard a guess and say that you risk destroying your engine if you put E85 in your tank without the necessary modifications.

 

[donR]

For modern turbo cars the idea is to run E30 or E40 by mixing 98 RON with E85 and using the stock fuel system. The BMWs were renoun for getting 25-35% hp gains with a minor exhaust mods (downpipe), but I don't believe there is much advantage with NA cars. 

There is an E30 tune for the 718 GTS 2.5t which goes from 374hp/450NM (91 Octane) to 461hp/613NM stage 1, or 480hp/644NM stage 2, so quite a gain,

However, the normal 93 octane tune claims 440hp/560NM, so not sure if mixing the E30 is worth bothering for the extra 20-40hp. 

[donR]

Just to follow up on this, APR recently released an E85 tune for the GT4 and GTS 4.0. Apparently there is plenty of ceiling in the fuel system of that engine and the modern components supposedly are compatible with the enthanol. 

The tune without any bolt ons is dyno'd at 488 HP with 361 FT-LBS (489NM). So not the torque of the turbo car but the hp gain is an outstanding increase for an NA car. Of course you would invalidate your engine and drive train warranty but beats forking out another $150k or so for a 495hp 4RS, given the engine reliability is there. There is also the inconvenience of being locked into E85 fuel with the APR tune but impressive none the less.